The Master Spy

"The Master Spy," Herbert Jenkins Ltd., London, 1937

When Gilbert Larose, one-time Australian detective, but now lord of a famous English manor, is approached by the British Secret Service for help on a dangerous mission, all his good resolutions to remain in retirement are forgotten. An elusive master spy of a foreign Power is stealing England's most vital defence secrets; detail after detail of new plans are being carried across the Channel, and the Secret Service is powerless to stop the leakage. This is the intriguing situation in which Arthur Gask, the Adelaide author, opens his latest Larose novel, "The Master Spy," which will begin publication in "The Advertiser" on Wednesday in serial form. Readers of Mr. Gask's previous books published in "The Advertiser" will not be disappointed in his new story. Larose's solution of the problem excels even his previous exploits in thrills and high-speed action.

CHAPTER I. BY THE DARK NORTH SEA
CHAPTER II. DISEASES OF THE SKIN
CHAPTER III. THE SPY
CHAPTER IV. THE SECRETS OF FOULNESS
CHAPTER V. LAROSE TAKES UP THE TRAIL
CHAPTER VI. THE CONSPIRATORS
CHAPTER VII. A DUEL OF WITS
CHAPTER VIII. HOT UPON THE TRAIL
CHAPTER IX. RUN TO EARTH
CHAPTER X. THE ADVENTURES OF MARGARET ADVENT
CHAPTER XI. DEADLY NIGHTSHADE
CHAPTER XII. THE KIDNAPPING OF THE PROFESSOR
CHAPTER XIII. THE HEATED IRON
CHAPTER XIV. THE BURIAL OF THE DEAD
CHAPTER XV. THE JEST OF LIFE

CHAPTER I
BY THE DARK NORTH SEA

"BUT I tell you, you have been marked down, Herr Mitter," said Dr. Gottlieb sternly, "and that word has reached us from several quarters that you are now under the suspicion of the authorities. I have made this special journey to warn you."

It was toward 9 o'clock upon one stormy summer night, and two men were conversing together in the low, oak-panelled and beautifully furnished room of an old house perched high upon a lonely stretch of cliff upon the coast of Suffolk, between the towns of Aldeburgh and Southwold. Glasses, spirits and a syphon had just been placed before them and the soft-footed butler had glided noiselessly from the room. Had the curtains of the long windows not been closely drawn, under a fitful moon could have been seen the heaving waters of the dark North Sea. The sound of the waves came up faintly into the room.

The speaker stirred uneasily in his chair and went on—"Yes, you have blundered, for at Whitehall, as you have always aspired to be, you are now in the way of being regarded"—there was rising anger in his tone—"as the master spy. Poachim writes us you are under the closest surveillance possible."

The smiling and good looking man he was addressing, seemed amused. "And when I tell you, my dear doctor," he laughed softly, "that that butler who has just left us is in the pay of the British Secret Service and indeed has been so for upwards of six months; that all my letters are opened before I receive them and that as a matter of daily routine my telephone is listened into—you will realise how closely I am beset." He made a grimace. "I regret to mention also that, at the local exchange here at Saxmundham, the two very charming young women, whose special duty it is to attend to all calls made and received at this house, are both of our own nationality, one of them being a graduate of a university and speaking four languages"—he threw out his hands in a gesture of mock despondency—"strangely enough, the only four of which I have myself any knowledge."

The eyes of Dr. Gottlieb burned like coals of fire. "And knowing all this," he gasped, "you are yet continuing to carry on and risking that they may pick up all the threads of our organisation!" He looked furious. "It is ruin. It is a catastrophe. It is almost treachery on your part."

"Treachery!" exclaimed Mitter, his eyes now blazing too. "You apply that word to me!" And then suddenly his features relaxed and his face broke into a pleasant smile. "No, no, Herr Doctor, there is no need for you to distress yourself. I am not quite a fool and I assure you my work in no way suffers because I am being watched." He shook his head emphatically. "They know nothing of our real organisation but are only being spoon-fed with discoveries of no importance to us at all." He looked scornful. "Suspect me, they undoubtedly do, but still they are learning nothing. I do not allow them to, and so confident that every one of my agents is under observation, they are under-estimating my activities in—to them—a most shocking way." He snapped his fingers together. "Why, every day I am driving a coach and four through the cordon they have drawn round me and carrying on as if there were no such organisation as the British Secret Service."

But his companion seemed in no way assured. "And how can you determine the extent of their knowledge?" he asked sharply. "You may be living in a fool's paradise all the time!"

Herr Mitter spoke with the patience of one humoring a little child. "Come, come, Doctor," he said persuasively, "if you are being served well enough to learn from the several sources you say you have, that I am suspected at Whitehall, have you learnt also that any of the special agents I am employing have been given away." His voice took on a sarcastic tone. "To mention only a few, have you learnt for instance that Mendel has been dismissed from Devonport Harbor, that Hern has lost his job at Chatham Dockyard that Krootz is no longer working on their super-submarines, or that Captain the Honorable R. T. J. Nathanial has ceased to be a trusted member of the staff at the Admiralty." He spoke slowly and impressively. "Have you heard now that suspicion has fallen on any of these men? And yet I can furnish the most convincing proof"—his voice was little above a whisper now—"that I am in almost daily communication with each one of them." He leant back easily in his chair. "Come now, be fair and just with me. Have you heard anything about any of these men?"

Dr. Gottlieb hesitated. "No-o," he admitted grudgingly, after a long pause, "we have had no ill news there, as yet."

Herr Mitter laughed gaily. "As yet! And I should think not!" He went on quickly. "And have you ever found that any of the information I have supplied to you was not reliable?" He slapped the table before him with his hand. "Did you not verify what I told you was going to happen, a week before—that the Admiralty had made secret trials of their new bombs upon the battleship Ajax, those hundreds of miles north of the Orkney Isles? Were you not forewarned that Sir Charles Montressor and his chief of staff were meeting the heads of the French army at Nancy at midnight upon the twelfth of last month? Have you not had the complete specifications of their new McHenry Torpedo, a torpedo infinitely superior to any of ours? Did you not learn——"

"Yes, yes, I admit all that," interrupted Dr. Gottlieb testily, "but you may not have been under suspicion then? Those are things of the past."

"Things of the past!" exclaimed Mitter. "The very recent past!" His good humor appeared to return and he became all smiles again. "But I know I have been watched for months and months and it has made no difference, for as I say, I have eluded them in all big matters and in trivial ones only, have allowed them to discover what they could." He nodded. "These petty discoveries of theirs have been my security, because they are thereby quite satisfied they are controlling all the channels of my enquiries."

"But which of the men working for you have they got to know?" asked Dr. Gottlieb with a frown.

Mitter laughed again. "A few who are quite useless to us; Witten who potters round the harbour of Sheerness asking foolish questions of all he meets; Van Rime who takes photographs with a pocket camera at Devonport; Joseph who hangs round the War Office, tapping the private lives of the junior clerks there, and the Scotchman, McBean, who receives £4 a week from me to become very drunk, hobnobbing with sailors in the lowest public houses of Portsmouth." He chuckled in amusement. "And these fellows address letters to me here that are opened before I get them, and copies of which are undoubtedly filed as valuable treasure trove at the counter-espionage headquarters in Whitehall."

"Well, what are your methods then?" asked Dr. Gottlieb after a long pause. "How do you manage to carry on?"

Herr Mitter shook, his head. "No, no, Doctor, as you know, our people have given me a free hand and I prefer to keep my own counsel. I can trust no one with my secrets, not even you"—he smiled ironically—"for with the changing fortunes of all in our beloved country, who knows how long you may hold the position you now do?"

Dr. Gottlieb ignored the last remark. "But it is a great responsibility for one man," he said slowly, "and if you are not equal to the task, I tremble to think what may be the consequences when The Day comes again." He hesitated a moment. "You might, too, take offence for some reason and become lukewarm to the cause." He eyed him intently under heavy brows. "We have no hold upon you, for, as a rich man, money is nothing to you, and I know you are receiving no remuneration for your services."

"No, you have no hold upon me," commented Mitter dryly, "but who should know better than you that none is necessary." He bent forward and lowered his voice to the merest whisper. "You are one of the few who have been told who my father was. Do you forget then that he was shot at the Tower and that his bones lie somewhere in some shameful and unhonored grave?" His voice vibrated passionately. "Am I not myself the son of a spy, and when the report of those rifles rang out in the dawn of that September morning of nineteen fourteen, should not my life have been sealed automatically for vengeance against the country of those who killed him?"

He rose suddenly to his feet with a gesture of impatience. "Add to my hatred of England then, the other obsession of my life—that one great fatherland should fulfill its destiny and become one day the conqueror of the world, and you have no need for any warranty that I shall not be faithful until death." He smiled bitterly. "I do not forget either, that my beloved mother died of her broken heart in a concentration camp in this country, and I have her, too, to avenge."

There was sympathy now in Dr. Gottlieb's expression, and he smiled for the first time. "Good!" he nodded, "then we can trust you, I am sure." He shook his head. "But it was disturbing to receive those reports that you were under such suspicion."

Mitter shrugged his shoulders. "And whose fault was that? Was it not your own man, Lieder, who betrayed us? He was never my choice, but was passed on to me by you, as a trustworthy man. Happily, I took a dislike to him at once and never admitted him to my inner circle."

Dr. Gottlieb nodded again. "Well, he is dead now, and I understand his punishment came quickly."

Mitter spoke sharply. "Yes, he died in this room, and maybe in that very chair in which you are now sitting." He pointed to a cluster of old weapons upon the wall. "I killed him with that stiletto there, stabbing him in the back as I passed behind him to get some cigarettes. No, no," he went on with a smile, as the doctor turned to glance apprehensively round the room, "there were no shadows then to receive his ghost, for he was killed on a bright and sunny afternoon."

"Certainly," replied Mitter calmly, "for there were even pretty girls playing tennis just outside. I heard the pings of the balls against the racquets as I was choking him so that he should not cry out." His face clouded at the memory. "He arrived at a most inconvenient moment, but I was obliged to seize the opportunity while he was here. I am sure he would never have come again, for I saw from the expression in his eyes that he had suddenly become suspicious of me."

Mitter pointed to a door leading out of the room they were in. "I hid it there in my bedroom, in a cupboard, and for two nights slept with it only a few yards away from my bed. I could not get rid of it before, because of the moon. Later"—he nodded in the direction of the window and spoke with some feeling—"it was given to those waters that will one day bear our transports when they come to conquer this proud and stubborn people."

"But did no one know the man had not left the house?" asked the doctor. "What were the servants doing?"

"Serving tea upon the lawn," replied Mitter. He laughed lightly. "And Herr Lieder disposed of, I washed my hands and went out to resume my interrupted game with our Chief Constable, Colonel Wedgewood." He looked very pleased with himself. "I was steady as a rock and beat him easily."

A short silence followed, and then Dr. Gottlieb asked thoughtfully, "And does the knowledge of the fact that you are being watched make no difference to the carrying out of the routine of your daily life?"

Mitter shook his head emphatically. "None whatever, and as long as I act as if I had no such knowledge, I feel assured I shall be quite safe. Whitehall is undoubtedly hoping to pick up all the threads of our organisation through me, and in consequence will leave me alone to the very last moment they can." He shrugged his shoulders. "I know I am sitting on a gunpowder mine, but I don't think I shall be here when it explodes." He waved round at the beautiful old oak-panelled walls and sighed heavily. "I could not be in more delightful surroundings, yet 48 hours before our aeroplanes come over to bomb London, I am quite aware I shall have to give them all up. Until then, however," he smiled, "I shall enjoy them with no worry upon my mind."

"But in what way do the people over here regard you," asked Dr. Gottlieb, his smile was very grim—"as an individual of our hated race?"

"Oh! Personally, we are not hated over here in England," replied Mitter quickly. He spoke rather contemptuously. "Britishers have not the temperament for a lasting, virile hate, and although they are nearly all of opinion we are going to drop poison gas upon their civilian population one day, there is no anticipatory resentment about it. No, my social status here could not be better, and I mix with the best county people. I am just regarded as a well-to-do, and perhaps rather eccentric, foreigner, who prefers this country to his own. As you know, painting is supposed to be my great hobby, and I have a beautiful studio here. I am not without some talent either, and there is a sea-scape of mine in the Academy this year." He nodded significantly. "As for my other life and the work I am doing for the fatherland—well, I have resources that no one would suspect."

"There will be no slip, big or little," interrupted Mitter sharply, "and make your mind easy about that." He punctuated each word with his hand. "Remember, nothing is done from this house that in any way touches my real work; no trail of any of my activities can be picked up here, and as Carl Mitter"—he laughed merrily—"I am no master spy." He threw out his hands. "Indeed, I am no spy at all, but just a clumsy bungler who makes happy the British Secret Service, because they discover so easily my little vain attempts to find out what is going on."

"But I wish you would give me some idea of how you carry on," frowned Dr. Gottlieb, "for I could then take back to our people a more reassuring report. I know, of course, that no communications of any important nature are sent to you here, and that you yourself compose the letters we write for you to receive at the house, still——"

"Have patience, Doctor, and tell them at home to have patience, too," interrupted Mitter. "I am doing the work you have entrusted to me, and, with no boasting, am doing it well. So be content with that. I cannot tell you what my ways are, for if my secret were once disclosed to you, you would have to pass it on, and it might get into wrong hands. Remember, if we are spying here, the British, are also spying among you, too, and we never know how highly placed our own traitors are." He shook his head. "No, if I told you everything, my confidence in myself would be gone, and I should no longer feel I was secure." His voice swelled in triumph. "Now, my confidence is absolute, and pursuing the way I am I know I have got the famous British Secret Service tied in a knot they can by no possibility unravel."

A long silence followed, and then, as if resigning himself to the inevitable. Dr. Gottlieb turned his thoughts in another direction, and glancing curiously round the room, apparently took in its beautiful furnishings for the first time. "Yes, you certainly have a nice place here," he remarked, "and that panelling must be very old."

"Two hundred years and more," replied Mitter with the enthusiasm of a connoiseur. "This house was built in the 18th century and there are ruins, just outside, that go back for nearly a thousand years." He rose from his chair and leading the doctor over to one of the windows, pulled aside the curtain. "See, those are the ruins of a Franciscan Priory whose foundations were laid in 1254, when a branch of that great order had its headquarters here." He pointed out to sea. "A score and more of churches, moreover, are supposed to be engulfed there, and upon stormy nights the villagers say they can even hear the clanging of the bells. This little hamlet of Dunwich was a big town once, with a large important harbor, but the sea is for ever encroaching and now a few scattered habitations are all that remain. Within living memory this very house of mine was three hundred yards from the sea, and yet tonight a bare sixty or seventy yards separate it from the waves." He sighed. "If I had any children they would live to see it topple over the cliff."

Then suddenly the sound of a car was heard outside in the drive and a few seconds later the bell of the front door whirred.

Mitter looked frowningly at his watch. "Ten minutes past ten and another visitor!" he exclaimed. "What's happening tonight?"

They heard voices in the hall and then the door of the room opened to admit a smart and very good-looking parlormaid. "A gentleman to see you, sir," she announced, "a Mr. Smith. He says he's very sorry to trouble you so late, but he won't keep you long. I've shown him into the morning room."

"All right," nodded Mitter. "I'll go and see him in a minute." Then when the door had shut behind the girl, he turned to Dr. Gottlieb. "Excuse me a minute or two will you. I'll go and see what the man wants."

"Oh! He's always allowed off duty at nine," replied Mitter, "to go for a walk and get some fresh air." He grinned. "But I expect tonight he's writing up a description of you and your car to give to the postman the first thing in the morning." He laughed. "I've got hold of some of his letters and they are very crude and inaccurate stuff, so I expect he'll be describing you as handsome and aristocratic-looking, with a furtive and secretive air."

He left the room still smiling, but once in the hall his expression changed. "Smith, Smith," he muttered. "I don't know him, but, of course, most probably that's not his real name."

He opened the door of the morning room to see the tall and closely muffled figure of a man standing in the middle of the room. The man was wearing his motor-goggles, but directly he saw who had appeared, he pulled them off and began quickly to uncoil the scarfe about his neck.

"The Ambassador!" ejaculated Mitter under his breath, "the haughty Count Von Rieben himself."

"Quick!" whispered the man, beginning to unbutton his overcoat. "Whose car is that outside? Who is your visitor?"

Mitter was all smiles. "It's quite all right, Count," he replied. "He's Herr Gottlieb, who has flown over to have a little talk with me."

"Dr. Gottlieb!" exclaimed Von Rieben frowningly. "What's he come for? Has anything gone wrong?"

"No, nothing," replied Mitter reassuringly. "He's only come to give me some news of which it happens I am already aware; pure routine business and of small interest." He went on quickly. "But you yourself, what has brought you here? It must be something important, of course?"

"Yes," snapped the ambassador, "most important." He hesitated a moment. "But as Gottlieb is here he may as well hear it at the same time. In fact, his being here is quite opportune and may save me a long despatch." He lowered his voice again. "But where's that damned butler of yours? As he didn't open the door to me, it may be just as well he shouldn't see me."

"Oh! Dempster's out, or in bed," replied Mitter airily, "but in any case you shan't meet him. Come into the library where the doctor is," and pausing for a moment to make sure there was no one about, he led the way across the hall.

With every appearance of annoyance, Dr. Gottlieb jumped scowlingly to his feet, as they entered the library, but then recognising who it was who was accompanying Mitter, his expression at once changed.

"His Excellency!" he exclaimed looking very surprised. "But this is a great pleasure!"

Von Rieben advanced and shook hands. "Not so much of a pleasure," he growled, "when you've heard what I've got to say." He peered hard at Gottlieb. "But you've brought no bad news, Herr Mitter tells me?"

The doctor shook his head. "No, our friend assures me that everything is going well and that the little scraps of information I have been able to furnish are no news to him at all."

Von Rieben seated himself at the table and, almost in one gulp, drank off the brandy and soda Mitter had mixed for him. Then he said sharply.

"Well, my news is not good," and his handsome face puckered into a dark frown as he blurted out:—"They've beaten us, these damned Britishers! They've got an invisible aeroplane!"

His listeners made no comment. Dr. Gottlieb regarded him wonderingly and Mitter stood frowning, with his mouth half open.

A deep hush filled the room, and, for a long minute, almost the falling of a feather could have been heard. Then, as if angered by the silence, Von Rieben burst out again. "An invisible aeroplane, I tell you! Don't you take it in?"

Mitter found his voice. "What do you mean?" he asked. "I don't understand you. What do you say they've got?"

Von Rieben laughed bitterly. "An aeroplane that you can't see, man. A plane that's invisible until it drops within 50 yards of you, and one that's almost noiseless as well." He ground his teeth viciously. "It's the greatest invention since aeroplanes came, and will give Britain the whip-hand over everybody else. No nation would dare fight her now."

"An invisible aeroplane!" ejaculated Mitter incredulously. "And you've seen it?"

"Been within 30 yards of it," scowled Von Rieben. "Seen it taxiing along before us like a grey shadow, seen it dart up into the sky and fade away like one, seen an enormous Union Jack trailing round and round a thousand feet up with nothing to show what was dragging it along." He looked contemptuously at Mitter. "You're an efficient director of our secret service, aren't you, to let an invention like this be sprung upon us and not to have had the slightest inkling of what was going on?"

"But how have you come to find out about it?" asked Dr. Gottlieb gruffly. "Let Mitter, here, learn how it is that you are before him."

Von Rieben calmed down. "I was shown it this afternoon," he said with a grim smile, and speaking very slowly so that every word should be taken in, "along with the representatives of nine other embassies, by special courtesy of the British Government. We were all motored separately to the Newmarket racecourse and taken on to the balcony of the Royal Box on the grandstand there. We had not been told what we were going to see, except that it was something that would be of great interest to our respective Governments, and until we began to assemble there it appears each one of us had imagined he was going to be the only favored one." He heaved a deep sigh. "Then this damned aeroplane was brought out and we were struck almost speechless in our astonishment. It was——"

"But why did they show it you?" interrupted Dr. Gottlieb sharply. "What was their idea?"

Von Rieben nodded vehemently. "To convince us of the undesirability of going to war with them, of course; to make us realise that this invention put all other countries at their mercy and that as long as they alone possessed its secret, peace at any price must be the policy of the whole world." He scowled. "Before the damned thing appeared the Prime Minister made a speech to that effect, when he had told us what we were going to see."

"But let us know exactly what happened," said Mitter with some irritation, "and we can judge then what this plane means." He looked towards Dr. Gottlieb. "Don't forget the doctor took his degree in physics and chemistry, and he'll tell at once if there's any practical value in the discovery."

"Oh! I'm not exaggerating," said Von Rieben sharply. "This aeroplane is a stroke of genius and gives Britain the complete mastery of the air. They could drop their bombs anywhere without any interference and everyone would be completely helpless."

He paused a moment. "Well, what exactly happened was this. Last week Lord Rodney himself rang up and asked me to keep this afternoon free, and today after lunch that Colonel Lendon, of the Air Service, called for me in a car and I was driven down to Newmarket. Then, as I say, I was taken up to the Royal box on the grandstand, and within a few minutes, to our mutual astonishment, the representatives of nine of the great Powers found ourselves assembled there. On the lawn in front were nearly all the members of the British Cabinet, along with the chief departmental officers of the army, navy, and air services. As we were ushered into the box we were all handed a pair of powerful Zeiss glasses."

He scowled angrily. "Yes, and all the time with all their extreme politeness, the damned Britishers were grinning as if they were on to some good joke. We could see they could hardly contain themselves in their amusement. Then the Prime Minister made the preliminary remarks I have told you, and pointing to a long wide stretch of scarlet canvas, spread on the racecourse before us and extending for about two hundred yards, looked at his watch and announced that the first plane would arrive in four and a half minutes and land in front of us."

Von Rieben mimicked a deep base voice. "It is now passing over Huntingdon, gentlemen, twenty-five miles away, but as its speed is upwards of three hundred miles an hour, I promise you it will be here to time. It will sound a syren and circle round us before landing."

The Ambassador stopped speaking and it was obvious he was struggling with some emotion. After a few moments, however, he went on:

"Well, there we stood in a strained and uncomfortable silence. I felt suffocating, and suddenly realised that I was holding my breath. We were all affected, and I saw old Ahsberg had bitten his lip until the blood had come. Then far away we heard a syren sounding, and Lord Rodney called out excitedly. 'Up with your glasses, gentlemen; it's coming from over there,' and he pointed across the heath."

Von Rieben cursed deeply. "But we could see nothing except the blue sky and some wisps of cloud that were trailing across. The sound of the syren, however, became louder and louder, and then it seemed to be screeching all round us. Then there was one final tremendous wailing blast, and, my God!"—he spoke with an effort—"down upon the scarlet canvas streaked a long, grey shadow. It stopped in less than a hundred yards, and there before our very eyes was a huge and almost transparent aeroplane. We could just very faintly discern the outline of its fuselage and wings." He struck his fist angrily upon the table. "Then out of it jumped four men. Three of them stood rigidly to the salute, while the fourth played the first bar of the British National Anthem upon a bugle." He sneered "It was intended to be most dramatic."

Von Rieben shrugged his shoulders. "Heaven knows! Some kind of glasseous substance, of course, but it was more transparent than glass, and even the propellers were made of it. The fittings also were nearly transparent, and Ahsberg, who once ran some armor plate works in Vienna, was of opinion they had been fused on. He said, too, he was sure that the fuselage had not been cast in one piece, but was built of a series of plates fused together, and that he could discern the shadowy lines where they had been joined."

Von Rieben scoffed. "They didn't give us the chance. We were prisoners in that Royal box, with thirty yards of the Royal enclosure separating us from the racecourse rails."

"But the men!" exclaimed Mitter "You must have seen them through the fuselage before they jumped out! They couldn't have been transparent!"

"Oh! we saw them right enough when the plane was slowing up," replied von Rieben sourly, "but by some means even their forms were partly obscured." He looked scornful again. "But a lot of chance you'd have of picking up grey figures in a machine travelling at 300 miles an hour."

"I don't know. I'm not an expert," snapped von Rieben. "All I could see was that it was a large bomber." He went on—"Then Lord Rodney looked at his watch again and announced that more planes were upon their way, and within five minutes three others had dropped down and taken their places behind the first one. The same shadows, swooping down like ghosts and practically without a sound. We were allowed to stare at them for a little while, then enormous Union Jacks were attached to their under-carriages, the bugle was blown again, and off went the four planes all together. They hardly made any noise, left the ground within 70 or 80 yards, and then we lost sight of everything, except for the trailing flags that seemed to rise almost vertically into the sky. Then for five minutes those flags were whirling about above us—with the dragging planes, however, quite invisible to our glasses—until finally they were dropped exactly in front of us, almost one on top of the others." He shook his head savagely. "The execution of everything was faultless, and I can conceive of a no more masterly exhibition."

Von Rieben was stirred instantly to renewed animation. "No, no, our mortification was not over yet. A sheet of the material used was held up close to us. It was about three feet square and certainly not more than half an inch thick. Then it was laid upon the grass just below, and a big burly mechanic struck at it a score of times with a huge sledge hammer. Nothing happened, however, and he might have been striking at a sheet of the strongest steel. Then the glassy sheet was propped up ten yards away, and from a hundred and more cartridges upon a tray any one of us was invited to pick out which ones we liked and fill the magazine of a heavy service rifle that was handed up. Then I emptied the magazine, firing point blank at the damned sheet. Then the sheet was handed up again for our inspection." He gritted his teeth together. "Not a sign of a mark or crack anywhere!"

"Faked fiddle-di-dee!" scoffed Von Rieben, "for the show was not over yet. A sheet of steel was next passed up to us—we were allowed to handle that and try to scratch it with a file. The sheet was about the same size as the other sheet but so heavy that it took two of us to lift it comfortably, for it was a good inch thick. Then it was propped up where the other sheet had been and Ahsberg choosing the cartridges this time, I emptied the magazine again." He spoke in an awed whisper. "Every bullet drilled a hole through."

A long silence followed and then Dr. Gottlieb asked thoughtfully, "Was the glass-like sheet heavy?"

"No," snarled Von Rieben. "Lord Roding lifted it up and waved it about in one hand."

"Almost as if he'd got nothing in his hand," replied the ambassador, "glass of very poor quality and very thin." He shook his head angrily. "There's no getting away from the fact that they've got hold of something no one's ever heard of before, a glass as transparent as air and tougher and harder than anything we know."

Van Rieben laughed mockingly. "Congratulations all round, champagne and sandwiches of caviar, and then good-byes as if we were all the best of friends."

Herr Mitter turned to Dr. Gottlieb. "But in your opinion, Doctor," he asked quietly, "except for what his excellency has just been telling us, as a onetime professor of physics, can you conceive it possible that an almost invisible material of such hardness as that sheet he has described can exist?"

Dr. Gottlieb hesitated. "It is just a matter," he said slowly, "of finding some substance whose refractive index can be made the same as that of air; something that will absorb hardly any light, and refract and reflect very little either." He nodded. "Remember, a sheet of white glass vanishes altogether when it is placed in water." He hesitated again and shook his head. "But, no, I could never quite imagine any hard substance being invisible in air."

"Well, you'll have to imagine it now,"' commented Von Rieben sharply, "for it exists and I have seen it with my own eyes."

"Still, whatever you gentlemen saw today," went on the doctor drily, and as if nettled by the curtness of Von Rieben's tones, "you will have great difficulty in convincing others that such a thing as an invisible aeroplane can really exist. The world will remain sceptical and——"

"Oh! will it?" interrupted Von Rieben unpleasantly. "Then it won't remain for so long, for three weeks today another demonstration will be given, and this time everyone can go who likes. An invitation is being broadcast to all the Governments of the world, inviting them to send their scientific men and the leading representatives of their press. I tell you there is going to be no secrecy as to the discovery, and the widest possible publicity is to be given."

"At Newmarket, where it did today," replied Von Rieben, "and special trains are to be run for all who don't go down in cars." He sneered. "Britain is determined we shall be all shown how helpless we are."

"Well, we shall be helpless only," scowled Dr. Gottlieb, "until we get hold of a piece of the material they use, and then"—he snapped his fingers—"the secret will speedily be no secret at all."

"And how are we going to get hold of a piece?" asked Von Rieben derisively. "They are not going to pass round bits as souvenirs." He turned suddenly and looked with great sternness at Mitter. "But now then, my friend, your department has been costing us a huge sum every year, and so you just tell me straight away where those aeroplanes are being built. Quick now, for you must have——"

"But you can't expect Herr Mitter to learn everything that is going on," broke in Dr. Gottlieb, still in annoyance at the ambassador's truculent tone. "The British can hide a lot of what they're doing in exactly the same way that we can, and——"

"Damnation!" exploded Mitter with great suddenness. "I have it. They're making the stuff on Foulness Island, just off the Essex Coast!" He nodded violently. "Yes, that's it, and for all these months they've been blinding us into believing they were experimenting with explosives there. There have been explosions going on day after day." He smiled triumphantly at Von Rieben. "Yes, your excellency, I can tell you what you want to know. They are assembling these aeroplanes either in Cardiganshire or Caithness, on the prohibited Government areas there, but, as I say, the material they are using is being manufactured upon Foulness Island."

"Because of the extraordinary precautions that have been taken for the best part of a year now that no one should approach the island," replied Mitter excitedly. He tugged open a drawer in his desk and producing a large ordnance map spread it out upon the table. "See, this is Foulness Island and it has been one of my special objectives for a long time now, indeed so much so, that I have a man stationed permanently at Burnham-on-Crouch to try to find out what is going on."

He calmed down all at once and continued in quiet and business-like tones. "Now listen to what I can tell you. This Foulness Island had always been a dreadful place to get to because the only approach to it is by a road over the Maplin Sands, only available at low water. The island, as you see, is five miles north-east of Shoeburyness and is cut off from the mainland by the river Roach and a wide deep creek. On the seaside, the tide recedes for more than five miles to the Maplin Light."

"Well, a little less than a year ago, the whole of this island was forcibly acquired by the Government, the land owners being compensated and the entire population turned off. After then no persons, except Government workmen were allowed anywhere near. Deep stretches of barbed wire were thrown all round the island, flanked by embankments about twelve feet high. Then in a few weeks a big factory had sprung up, but in such a position that no one on the mainland can get within two miles of it. Also a huge, and partly underground aerodrome was constructed."

He nodded significantly. "Everything was done at express speed and we reckoned that at one time more than a thousand men were being employed. Every day at low tide there was an almost endless procession of huge lorries along the road over the sands. Then suddenly, with the factory and the aerodrome completed, this road was closed with more barbed wire entanglements, the island was completely isolated, and for many months now there has been no communication except by plane."

"No, and not even a landing stage. The seaside of the island is as deeply wired as the land side, and as far as we can make out with the most powerful glasses, there is only one single opening leading on to the sands. I tell you every scrap of material for the factory and every scrap of food for the workmen is now being carried on to the island by planes."

"Undoubtedly, I should say!" replied Mitter. "But it's all done at night in tremendously fast planes and we have never been able to find out where they land. We wanted, of course, to try to get in touch with one of the men." He turned to Dr. Gottlieb. "But look here, Doctor! Could they make glass out of that sand by the island?"

Mitter threw out his hands. "Well, there you are. They've got the material they want on the very spot."

In low voices they talked on for a long time, with Von Rieben irritable and restless, Dr. Gottlieb very thoughtful and only Mitter, apparently, easy in his mind.

"Well, never mind," said the last, confidently, "it can be only a matter of a little time before we've got hold of a piece of that glass and are making it ourselves." He nodded. "With all the amount of material they must be manufacturing now and with the hourly increasing number of hands it must be passing through, we shall soon find someone to give them away."

"You must find that someone quickly," scowled Von Rieben, "for when we are ready, we can't go on keeping everything up to concert pitch indefinitely." He shook his head angrily. "I had hoped that within twelve months we should have been over here." He turned to Dr. Gottlieb. "Well, it's gone 1 o'clock a long time ago now, and you'd better follow back behind me. We will find out then if anyone is attempting to trail us. We'll go by way of Bishop's Stortford, so that if anyone has been given the office to pick us up as we enter town by the main road, we'll be able to give them the slip."

Ten minutes later and the house was all in darkness save for the one shaded light over Herr Mitter. He was deep in the pages of the London Directory and feverishly jotting down the names of those firms in the city who were makers of plate glass.

CHAPTER II
DISEASES OF THE SKIN

DR. SMITH had a suite of professional Chambers in the huge block of buildings known as Moon Buildings, upon Finsbury Pavement, and according to a notice, among some many scores of others, upon the wall of the vestibule, his speciality was 'Diseases of the Skin.'

If you had looked in the Medical Directory you would have seen that his Christian names were Raymond Colin, that he was a Doctor of Medicine of Edinburgh University, and that he had taken his degree in 1884. So you would naturally have assumed that he must be an old man, well over seventy, and therefore of considerable experience in his profession.

But it happens you would have been quite mistaken, for this particular specialist in diseases of the skin had, indeed, never seen the inside of a hospital, except once, when, as a small boy he had had his leg broken in a street accident in Leeds; and again, too, seventy years previously, his mother had not as yet been born.

He was, however, practising with the diploma of a Dr. Raymond Colin Smith who had died some seven years before, in what had at one time been known as German East Africa, and as the defunct doctor had had no relatives to mourn his loss, and no one interested in his private affairs, and as, moreover, his handwriting had been easy to imitate, news of his decease had not reached the Registrar of the General Medical Council in London.

Still, if he had had no proper medical training and no qualified experience in his adopted profession, this pseudo Dr. Smith must, nevertheless, have been something of a clever fellow, for with the knowledge acquired from the study of half-a-dozen or so of old and musty-looking volumes upon a shelf in his consulting-room, he had undoubtedly relieved the troubles of not a few bad skin sufferers.

One of the lift-men in the building, for instance, thought the world of him, for had he not cured this lift-man's wife of a form of weeping eczema, when two other practitioners had been able to do nothing for her?

In consequence, this grateful husband had recommended several patients, and would have recommended many more had not the doctor been so high in his charges. Indeed, it almost seemed as if Dr. Smith were desirous of choking off patients by charging them so much, and, further still, the very irregular nature of his attendances at his consulting-room drove a lot of people away, for upon very many mornings would-be patients, after waiting an hour and longer for him to put in an appearance and there being no sign of him, had gone off grumblingly to obtain the services of someone else.

The doctor employed no nurse or female attendant, but upon those days when he did consult at his chambers, he was always preceded by a man by name of Jasper, who used to open the windows and air the rooms, and later in the day this same man would return to do the tidying up when Dr. Smith had gone.

Even by sight Dr. Smith was known to very few of the other tenants, for his rooms being upon the first floor he seldom used the lift and, as there was a second entrance into the building from Fore street, the chances of anyone encountering him were diminished by half. His comings and goings, therefore, would at all times have been difficult to follow, especially as the fourth room of his suite of chambers had a second door opening into a different passage round the corner, thus enabling him to leave unseen, even when, it might be, a would-be patient was actually knocking upon his waiting room door.

His consulting-room was very plainly furnished with a shabby, faded carpet covering the floor. It contained a desk, three chairs, an old surgical couch, a microscope upon a small table, some dirty test-tubes in a stand, the few books we have mentioned, and a dusty pile of out-of-date medical journals in a corner.

The doctor himself certainly did appear to be an old man, well up in years, for he stooped a lot and was most slow and deliberate in all his movements. He had long, grey hair and a grey beard that hid from view any collar he might be wearing. He had big bushy eyebrows and wore large, broad-rimmed, dark glasses.

When a patient was consulting him he spoke in tones hardly above a whisper. Then he looked very grave and solemn, nodded many times, and always had recourse to a huge magnifying glass when he was examining any spots or rashes. He hummed and hawed a lot in his diagnosis, and was never inclined to give a very decided opinion. He asked everyone if there was any consumption in their family, and indeed seemed always to suggest that the ancestors of all who came to him must have been suffering from unpleasant and unpopular diseases. His one unvarying prescription was for a paste of vaseline and oxide of zinc, and he always advised every patient that fine oatmeal should be used for washing with, instead of soap. He whispered, too, the injunction to drink plenty of water and avoid greasy foods. He never encouraged anyone to come again.

In addition to the consulting room, three other rooms comprised the suite; a waiting room that contained a table and half a dozen chairs; a small room with a sofa, a cupboard and a large safe let into the wall; and finally, there was a much smaller room, with a gas stove, a few cooking utensils, and some plates and cups and saucers. It was this last room that had the second door opening into the other passage.

His man, Jasper, was about forty years of age, and was always dressed quietly like a gentleman's servant. He was cold and reserved in manner, but for all that, upon occasions was not averse to stopping for a little chat with the lift-man.

"The only thing regular about your governor," said the latter one day, "is the time he goes out for his lunch. One o'clock to the tick and he's always ready for his feed. Where does he live? Is it far from here?"

"He's got a flat in Fitzroy Square," replied the servant, "and I look after him. He's no trouble, for all he does is to read and write."

"Well, he certainly doesn't bother much about the practice here," remarked the lift-man, and then he added curiously, "but he gets a lot of letters. Do you know who they're from?"

"Mostly from other doctors," replied the servant. "They write to him for advice from all parts of the world. He's got a great reputation."

One morning when Dr. Smith was consulting with an elderly woman who had come to him about a rash upon her legs, he heard the bell of the waiting-room buzz, and, as per invitation inscribed upon the door, the footsteps of someone who had opened it and let himself in. The doctor's eyes glinted as if he had recognised the footsteps, or as if a caller whom he had been expecting had arrived, and with the hurried writing of the prescription for the usual zinc oxide and vaseline, and the stereotyped injunctions to use oatmeal instead of soap, and drink plenty of water, he cut short the consultation and dismissed the woman.

Then, taking a small automatic pistol from one of the drawers in his desk, and fitting a silencer on to it, he thrust it in the right hand pocket of his coat. Then, after a careful but hurried scrutiny of his face and hair in a small mirror, which he produced from another drawer, he composed his features to their usual calm, and opening the communicating door between the consulting and waiting rooms, invited the new arrival to step in.

"Good morning, Mr. Leaver," he said in the low whispering tones he always used. "I've been hoping you would come, for several days," and closing the door behind him, he beckoned to his visitor to take a seat.

The man he had ushered in was quite young, and could not have been more than six or seven and twenty. He was smartly dressed, and held himself confidently. He had a good-looking and intelligent face, marred somewhat, however, by a hard and bitter expression. His eyes and chin spoke of courage and determination. Of quite a superior type, he was an old Charterhouse boy who had once followed the profession of a chartered accountant. Three years previously, however, he had been sentenced to eighteen months' imprisonment for embezzlement. He had known Dr. Smith for about a year. He looked at him now with a lazy smile, as if for some reason he were rather amused.

The young man nodded. "Yes. I've had some luck this time. I've located one of the men who's working there. His home's in Manor Park."

"Splendid," ejaculated the doctor, looking very pleased. "Then you picked him up in the way I suggested?"

"Yes, and I was fortunate, for he came from the third firm I tapped," was the reply. "He was head blower in Wilkinson's Glass Works in Spitalfield, and he took himself off at a moment's notice last March. I palled up to one of their men as he was leaving work one night, and pretended I wanted to know where a chap called Irons lived, who had once been one of the foremen there. Of course the man swore I was mistaken, and over a couple of pints, ran over all the men in good positions who had left the firm this year. There were three of them who had suddenly given notice, and no one knew what for."

Dr. Smith clicked his tongue triumphantly. "Exactly what I thought had happened. The Government would, of course, engage the very best!"

Leaver continued. "This man only remembered where one of them lived, however, and he was deuced hazy about that, only thinking it was somewhere in Manor Park. This chap, he said, was a Tom Skelton and he used to come to work on a motor bike. That helped me a lot, for I began a round of all the garages in Manor Park and soon found one that used to supply this Tom with petrol. That's how I came to get the exact address."

"But how did you find out he is now working on Foulness Island?" asked the doctor sharply.

"I suspected it at once," replied Leaver, "and now, after three days' enquiry in his neighborhood, am quite sure. He's got a wife and two children, but only comes home to them once a month and then, each time, for five days. No letters come to the house through the post when he's away, but his wife writes plenty, for she's always borrowing stamps from the neighbors." He nodded. "In passing, my idea is she goes and calls for letters somewhere. Well, she tells everyone her husband is working in Birmingham, but when asked where, she always says she can't remember the name of the firm."

"Go on," said the doctor, because Leaver had stopped speaking to take out and light a cigarette.

"Then according to all reports," went on Leaver, "this Skelton's altered a lot in his ways and, when he meets his friends now, won't talk about his job. He avoids them as much as he can, too, and never goes to the local pub. Again, he's taken to living in a much better style of late, as if he were getting a considerably higher wage. He's bought an expensive sidecar outfit and both he and his wife have got leather motoring coats. He looks bronzed and sunburnt, too, when he comes home, as if he'd been getting plenty of fresh air. Also——"

"But all this is no evidence," interrupted the doctor testily, "to link him up with working on Foulness Island."

"Yesterday afternoon I saw his wife go out with the two children," went on Leaver, as if he had not heard the interruption, "and, knowing the house to be empty, waited an opportunity until no one was passing in the street, and then slipped round into the backyard. I got into the house through the scullery window. I found it very nicely furnished, but all with new stuff, and there was an expensive wireless in the parlor. Then making a hurried search everywhere, I came upon a letter in the tea-caddy from this Tom Skelton to his wife, dated only two days ago, and I made an exact copy." He nodded triumphantly as he took out his pocket-book, "Now you just listen."

He searched for a few moments and then extracting a small piece of paper, proceeded to read out:—

"I am always glad to get your letters and know the kids are well. I am all right, too. I don't write more often, because there is no news to tell. As I expected I shall be coming home again on Friday, the sixth, for the usual five days. I don't know the exact time, of course, but expect it will be pretty late as usual. I shall try and bring some more cockles, but I have learnt the tip is to soak them in salt water to make them throw out that sand.—

He leant back in his chair. "Now what could be more conclusive than that. First—he gives no address and the omission is undoubtedly intentional, for he is a methodical man, as is shown by his not only mentioning the day on which he is writing, but also adding the date as well, 'Tuesday evening, September 3rd.' Then, second—the Essex coast right round from Leigh-on-Sea up to Clacton is noted for its cockles and they are horribly sandy little beasts to eat. Yet a third thing—he writes about the cockles 'throwing out the sand,' and that can only mean that they will be still alive when he brings them to Manor Park, which, of course, shows that they will have been gathered that same day." He laughed. "Who ever heard of cockles coming from anywhere near Birmingham."

"Yes, I think you've scored a bullseye this time, for there is undoubtedly mystery about that letter, and it fits in with exactly what we should have expected he would write, if he were on secret work on Foulness Island. Naturally, of course, he would have been forbidden to put any address." He nodded again. "Yes, I believe as you do that we shall find he's one of the men we have been looking for, and the thing is now to determine what we must do next."

A short silence followed and then with a deep sigh, as if of regret, he made an almost imperceptible shrug with his shoulders and asked Leaver to open the window.

"We shall have to put up with the noise of the traffic," he said, "but the room is stuffy and I feel rather faint." Then, when the young man had complied with his request, he leant back in his chair and regarded him very intently. Several times he opened his mouth as if he were about to say something, but then each time he stopped himself and stared on.

Leaver was now leaning back too. He had again that half smile upon his face, as he blew ring after ring of smoke into the air. All along his manner towards the doctor had been rather casual, and it seemed as if, having made his report, he did not intend to exert himself to continue the conversation. The sounds of the traffic in the street below came up noisily into the room.

At last the doctor spoke again, and he had now to raise his voice a little to make himself heard.

"Now let me see," he said slowly. "Your pay is due next week, and if it turns out you are right about this man, there will be the promised bonus of £50, as well." He leant forward and looking hard at Leaver, began to speak more quickly. "You are quite satisfied with what I am paying you, are you not? There is no thought at the back of your mind that you should be receiving more?"

"Certainly not," replied Leaver with no hesitation. "I have always considered the pay quite good."

Dr. Smith spoke musingly. "I picked you out of the gutter, didn't I? You had not many rags to your back when I found you and you were down and out in every way! You couldn't get work anywhere and you were nearly starving!"

Leaver nodded coldly. "Exactly!" he replied. "My record was too bad for anyone to employ me." He added bitterly. "One little slip in this damned country and you go under for ever." His lip curled. "You may just as well become an habitual criminal at once. You are driven to it."

"And I give you £10 a week," continued the doctor, "and a life of adventure with some danger and some risk!" He smiled whimsically. "Now what more could a young man want? Surely you must regard me as your benefactor."

"Most certainly I do," nodded the young man. "You are making life very pleasant for me. I am having quite a good time."

The doctor slid his hand very slowly down on to the little automatic in his pocket, and suddenly leaning forward, rapped out with a snarl—"Then why are you spying upon me now, Mr. Leaver?" His whisper was like the hiss of a snake. "Why are you selling me—you Judas?"

Leaver, with all his habitual air of self-control, at once looked the very picture of consternation. His jaw dropped and his eyes opened very wide. He was speechless in his astonishment.

"No, no," went on the doctor furiously, "don't you attempt to deny it. You are having me watched."

Instantly then Leaver found his voice. "It's a lie," he exclaimed angrily. "I'm not and I've never even spoken about you to a living soul. I've never mentioned you to anyone since the first moment I came to know you."

The doctor made a gesture of contemptuous disbelief, and, with long forefinger upraised, slowly punctuated his next words. "Upon two occasions last week you followed me when I went out for lunch, and on Thursday and Friday afternoons there was a man, disguised as a railway porter, waiting outside this building to trail me as I went home. All these attempts were, of course, associated together and part of one plan." He shook his fist menacingly in Leaver's face. "You are in someone else's pay, you wretch. You are trying to sell me, I say."

Leaver had now in part recovered his composure. "No, I am not, Dr. Smith," he said firmly, but at the same looking very shame-faced. "Nothing of the kind is going on, although I realise now that I have been very stupid." A smile curved to his lips. "Certainly, I did follow you, and I confess I was that porter myself"—he made a grimace—"but as I made no discoveries, no harm has been done and all your secrets are safe."

The doctor appeared incredulous. "You were that porter!" he exclaimed. He gritted his teeth together. "Then you admit you are double-crossing me?"

"No, I don't," returned Leaver instantly. "There has been no double dealing at all and I tell you I deny I have spoken about you to anyone. I have just been too curious about you and that is all. As you are my employer I ought, of course, to have minded my own business." He reddened uncomfortably. "I realise that my attempt to trail you was a dishonorable thing to do."

The doctor's face was grim as death. His grip upon the little automatic tightened and his thumb felt gently along towards the safety catch. Then he half drew the pistol from his pocket. "Have you made any such attempts before?" he asked coldly.

"No," was the curt reply, "and you can rest easy I shall make none again." He nodded his head jerkily. "I apologise to you."

Dr. Smith looked icily disdainful. "And your only explanation is that you were curious!" he sneered. "Am I really expected to believe that?"

"Yes, you are," was the cool rejoinder, "for it's the truth and in the circumstances only what you could reasonably expect." He quickened his words and spoke with some anger. "Here have I, for nearly a year now, been doing dirty jobs for you, some of which, if found out, would certainly have landed me into penal servitude. Damned dirty jobs—playing the traitor, spying for the enemies of Britain and selling her"—he laughed bitterly—"I don't even know to whom."

He slapped his hand upon the desk. "Yes, that's where the thing hurts—helping some damned country, perhaps, that all my life I've been brought up to hate. And there you sit, every time I come for my instructions, like an old mummy in some museum, with your stained hands, your wig and your false beard." He scoffed contemptuously in his turn. "I know for certain that you're not the Dr. Smith of Moon Buildings down in the medical directory, for your ears are not those of a man as old as he must be." He calmed down all at once and sat back in his chair. "Good heavens, man, if I weren't curious I should be a blithering fool, and by no means the type of individual to have found out all I have for you." His jaws closed with a snap. "And that's that, Dr. Smith."

The doctor was still fingering the safety catch of his little automatic, but his face was quite expressionless as he said slowly:—"Give me in detail your exact procedure"—he hesitated a moment—"last Friday afternoon, in detail, please."

Leaver looked in no wise abashed, indeed now, he seemed to be deriving some amusement from the doctor's questions.

"I came into the building through the Fore street entrance," he began, "at about a quarter to four and used the staircase, as I always do. I had to saunter about for several minutes until there was no one in the passage, and then I put my ear to your door to make certain you were there. I heard a woman talking and had just time to bolt away before you showed her out. I heard her say 'Good-bye, Doctor.' Then I would have liked to wait in the passage to make sure which way you went out, but didn't dare to do so because it happened the lift-man had seen me three times, and I thought that the third time he was eyeing me very suspiciously. So I went down and waited outside on Finsbury Pavement until six o'clock came, and then, not seeing you, I guessed I had made another miss, and that you had gone out the other way."

A thought seemed suddenly to strike him, and he went on triumphantly—"And that proves I was acting all upon my own, for if I'd been working for anybody else there'd, of course, have been a watch set at both entrances to catch you."

"Did you come up and listen at my door again," asked the doctor, "to make sure I had actually gone?"

"No. That lift-man had scared me, and, besides, I had got sick of the whole business. I was tired and thirsty."

"Went to a restaurant in Great Portland street to get a feed, then on to the Juno to see 'The Jest of Life,' and finally to Beak street, to my lodgings. I was home by eleven o'clock."

"Eight minutes past," corrected the doctor dryly, "and it was just striking the half hour when you put out your light."

With a sigh that seemed one of great relief he drew out the hand in his pocket, and with a quick, decisive movement, laid the little automatic upon the desk before him. "Pull down the window, please, Mr. Leaver," he went on with a grim smile. "The stuffiness of the room no longer upsets me." His smile became more pleasant. "The atmosphere has cleared, and the noise of the traffic is no longer needed to deaden any sounds in here."

With a frown the young man did as he was requested, and then resumed his seat, with his heart, however, beating quickly as he eyed the pistol now in full view before him.

"So that was intended for me," he scowled with a slight catch in his breath. "You were going to murder me, were you?"

The doctor held up his hand in protest. "An unpleasant word," he replied, "that should never be used among friends"—he smiled genially—"for I see, after all, we are going to be friends." He nodded in the direction of the pistol. "Yes, that was intended for you, and if you had not been truthful in every particular just now"—his voice hardened—"you would have gone out from here in a packing case to-morrow, for I was quite aware of everything you had been doing, and my questions were only put to try you out." He leant over the desk. "Do you know, young man, you have had a very narrow escape, or, indeed, several narrow escapes, for I have been having you under observation during every hour of the twenty four for longer than a week, and if last Friday, after your fruitless waiting for me here, you had gone into a telephone box, or had only happened to post a letter that night"—his voice was very low—"quite apart from anything that has been happening this morning, you would not be alive now."

Leavers face was damp and white. "And you talk about us being friends!" he ejaculated jerkily, "after telling me that!"

"Why not?" asked the doctor with great pleasantness. "We understand one another now, don't we?" He shook his head. "I never quite thought you were going to betray me, and all along put your actions down to just curiosity, as you have explained." He shook his finger warningly. "But no more of it, Mr. Leaver, please, for I shan't overlook it a second time."

Leaver eyed him sullenly. "Who are we working for?" he asked sharply. "Which country is it?"

The doctor looked angry. "Mind your own business," he began, "and don't——" but then suddenly he stopped speaking. He drummed with his fingers upon the desk, he bit his lip, and he stared thoughtfully out of the window. Then at last he turned again to the young man and smiled.

"Yes," he said, "you have a right to know, for you are not of the ordinary run of people we employ." His whispering voice was lower than ever. "The Soviet, my friend. We are working for Russia."

"Of course we are," laughed the doctor, "and our work is in consequence only a matter of routine." He spoke impressively. "You don't appear to understand things, Mr. Leaver, and realise that every Power in times of peace, far more than in times of war, has its secret agents in every other country. It is routine, I tell you, for they all want to know what one another are doing." He spread out his hands. "Why, what Britain spends on her secret service is publicly given out every year in the Estimates, and this year I saw they are allowing for nearly half a million pounds."

The doctor bowed and smiled. "I beg your pardon, my friend. I was born in Moscow but was educated over here. I speak English faultlessly. As a matter of fact, I am a Master of Arts of Oxford University." He went on impressively. "The position is this. As you say, Russia is at present friendly with England, and at the same time she is friendly with other countries." He shook his head. "But that does not say she will always be friendly, does it? No, of course not! And so, as an insurance for the future, she has to keep herself in touch with all that is going on everywhere. That is why such individuals as I have these enquiries made, and why, again, I employ such men as you. Now do you understand?" He regarded Leaver intently. "Does this explanation satisfy you?"

Leaver hesitated a moment, and then nodded. "All right," he said. "I'll believe you."

"Of course you will," laughed the doctor, "for its the truth." He spoke earnestly. "I should be very sorry indeed to fall out with you, for you are intelligent, well educated, and have plenty of courage. You are just the very kind of man wanted for this particular work."

"Fall out!" exclaimed Leaver, looking very reproachful. "That's putting it mild, isn't it? You were going to shoot me!"

The doctor's voice was very stern. "Listen, Mr. Leaver," he said, "our investigations in this country are just as criminal acts now, as they would be if an actual state of war existed. The only difference is that the punishments for discovery are not so severe." He spoke with some irritation. "If then you were successful in giving me away, not only I, but many others as well would undoubtedly be sent into penal servitude. So naturally we will go to any lengths to safeguard ourselves and the life of anyone who would betray us becomes a mere bagatelle. You understand that?"

The doctor nodded. "And you have been so for a long time now." His eyes narrowed. "Don't you forget, my friend, you've not been altogether too squeamish yourself, and when you got those fuses for me from Woolwich Arsenal last May—remember—you put out that sentry with your bar of lead and we've never learnt to what extent you injured him." He nodded again. "So if you're caught it may not be just a question of imprisonment for you, as you mentioned just now, for you may indeed have all along been wanted upon the capital charge. Also, there's that little affair when you pushed the watchman over into the dock at Chatham." He rubbed his hands together and chuckled maliciously. "You don't know that he wasn't drowned?"

"All right! All right!" exclaimed Leaver quickly. "You needn't bring those things up. I'll carry on as you want to."

The doctor was at once all smiles again. "Of course you will, for you're a sensible fellow." He pulled his chair up to the desk. "And now after this little digression let's get back to business again." He considered. "Well, you must find some excuse to get speech with this Tom Skelton, of Raymond street, Manor Park—oh, yes, I know the exact address, for you were followed to the house—early on Saturday morning, and then come straight back here and tell me exactly what kind of a man he is. We must be very sure he is the type of individual we dare approach, for we can't risk his going straight off and giving us away to the authorities. Now is there anything more we need discuss?"

Leaver hesitated and then spoke with studied carelessness. "I think you might give me a few pounds on account," he said. "I've run a bit short."

"You shall have £10," said the doctor, and producing a wallet from his pocket he took out a thick wad of notes and began counting some off.

Instantly then, Leaver sprang to his feet and in a lightning movement reached over and snatched up the automatic on the desk. Then, pointing it straight at the doctor, he stepped backwards to the window, and with his disengaged hand finding the catch, he pulled it up sharply and the noise of the traffic at once came up into the room.

"Now, Dr. Smith," he exclaimed triumphantly, "what about it? The tables are turned, my friend."

The doctor's mouth gaped in discomforted surprise, and he half rose from his chair, but then quickly recovering himself, he sank down again and chuckled as if he were in the enjoyment of some good joke.

"Excellent!" he exclaimed in great good humor, and appearing in no wise put out. "I did well to form the high opinion of you that I have, for I see you are quick to seize an opportunity and are not wanting in resource." He eyed him tauntingly. "But the thing is—would you dare to shoot? Have you courage enough?" He scattered the wad of notes over the desk. "Look, there is more than £100 here, and"—he pointed to the adjoining room—"you'll find a good £1,000 in the safe." He nodded confidingly. "That silencer, too, makes very little noise."

Leaver spoke with perfect self-possession. "I would not shoot you for money, Dr. Smith," he said, "and so you're quite safe there." His eyes gleamed. "But what about taking off those glasses and that wig and beard. I want to see what manner of man my esteemed employer is."

Dr. Smith turned his eyes down and began gathering up the notes. "All right," he said testily. "I suppose I'll have to do it," and then he added with a scowl, "but it'll cost you £5 a week, for I shall dock your pay that much."

For perhaps ten seconds Leaver still stood covering him, and then, turning sharply, he pulled down the window and stepped over to the desk.

"You can keep your wig on, Doctor," he said quietly. "It was only a joke," and he put the pistol back upon the desk.

"Ho! ho!" exclaimed Dr. Smith, as if rather surprised, but without looking round, and continuing to gather up the notes, "then you are confident you are safe with me after this impudent display of insubordination?"

"Yes, quite," replied Leaver. "I don't think you are spiteful, for you take much too broad a view of life."

The doctor paused now and glanced up at the young man with a cunning look upon his face.

"But I noticed you shut that window before returning this pistol. You were bent upon minimising your risks!"

Leaver colored ever so little. "You might perhaps have been annoyed for the moment, and I thought——"

"You did quite right," nodded the doctor with a smile, "and I think the more of you for your precaution. No. I'm not spiteful, and in proof of it—here I'll make you a present of the pistol. It may come in useful some day, and if it does you'll find the silencer is a wonderful invention. The shot can hardly be heard."

Leaver colored still more. "It's very nice of you, Doctor, I am sure. I'll take it with great pleasure. You are a good sport, whoever you may be."

"Yes," remarked the doctor musingly when he was once more alone, "it is always better to work with a man of his class, for whatever he does, as an old Charterhouse boy and a gentleman, he'll always retain something of his sense of honor." He nodded. "Yes, I did well to let him go."

CHAPTER III
THE SPY

ABOUT eleven o'clock, upon the following Sunday morning Tom Skelton was sitting upon one of the seats on the Esplanade at Southend seemingly at peace with all the world and very pleased with himself.

He was munching assiduously at 'two pennoth' of shrimps, which he from time to time abstracted from a small brown-paper bag, and so tender, succulent and tasty were these little denizens of the vasty deep that he was devouring them, heads, tails, scales and all, with no qualms whatsoever that they would upset his digestion.

Some fifty yards away, upon the sands below, his wife and two little ones were building a huge sand-castle, and he was lazily regarding them with the proud feelings of the admiring husband and father. Every now and then, however, he shot a glance up at the big clock upon the pier to determine how much longer it would be before he could obtain a refresher from the nearest public house.

He was a contented, happy-looking man, rather short and stout, with a round, clean-shaven face, and big, innocent blue eyes. He had chubby cheeks and a small mouth, and he was wearing a suit of good, but obviously ready-made, clothes.

For a long time he had the seat all to himself, but then just when he had munched the last shrimp, and made a ball of the small brown-paper bag and thrown it at a sparrow, a very well-dressed man, with a monocle and smart bowler hat, strolled up, and seated himself at the other end.

Tom took a good squint at the newcomer. "A nob!" was his muttered comment, "a real toff! I must get a pair of spats like those myself. Why shouldn't I? I've got the cash."

The gentleman took out a cigar from an elaborate case, and, clipping the end with an expensive-looking cutter, moistened it delicately with his lips and then proceeded to abstract a little silver match-box from his waistcoat pocket.

"Whew!" whispered Tom, "wax vestas! I'll get a box of them, too. Yes, he's a real nob, he is!"

But the stranger had suddenly frowned, for the match-box was empty. For the moment he looked most annoyed, and then apparently noticing Tom for the first time, he turned with a courtly gesture, and smilingly suggested the gift of a match.

Tom complied with alacrity, and the stranger, having lighted his cigar, returned the matches with a bow and grateful thanks. Then suddenly, it seemed as if he were in the way of being very puzzled about something, and, taking the cigar from his mouth, he eyed Tom very curiously.

"Good gracious!" he exclaimed after a moment, "but it's Mr. Skelton, I am sure; Mr. Thomas Skelton, of Manor Park. Yes, yes, it must be, for I never forget a face." He chuckled in quiet amusement. "No, of course, you don't know me, but I remember seeing you"—he dropped his voice and looked round to make certain that no one was near—"on Foulness Island." His voice became now the very merest of whispers. "You are one of the glassblowers there."

Tom looked the very picture of embarrassment. He screwed up his eyes, he opened and shut his mouth, and he swallowed hard. Then he turned his face away and, without saying a word, gazed stolidly out to sea.

"Oh! it's quite all right," laughed the stranger. "I'm a Government official myself." He dropped his voice again. "My name is Worley and my work lies in Whitehall. As a matter of fact, it is I who sign the wages-sheet for you chaps on Foulness, every week." He spoke very confidingly. "It happens in this way that I come so particularly to remember you. I was on the island"—he hesitated—"let me see. Yes, it was just after you first went there, about last March, I think, and chancing to catch sight of you I was struck at once with your likeness to a cousin of mine, Commander Worley, in the navy. 'Who's that man?' I asked at once, and then they told me, and so ever since when I see your name upon the pay-sheet I think of you." He rattled off: "Mr. Thomas Skelton, 17 Raymond street, Manor Park. Age 34, has a wife and two children, and for seven years was head-blower at Wilkinson's in Spitalsfields." He took a long puff at his cigar. "My conscience, but what a coincidence meeting you here when you only came home for your leave on Friday!"

Tom still looked rather embarrassed. "But we're not allowed to talk about anything, sir," he said. "We are sworn to the utmost secrecy."

"And quite right, too," agreed Mr. Worley. He nodded. "As a matter of fact again, it was I who drew up that regulation." He smiled all over his face. "Well, did you bring back any of those cockles this time? They're devilish sandy little things, aren't they?"

Tom smiled back now. "Yes, they are, sir," he replied, "but the tip is to soak them in warm, salted water and then they throw out all the sand themselves."

"Ah!" exclaimed Mr. Worley delightedly. "I must remember that. One of the heads there often brings me a little parcel of them and, although I have never dared to tell him so, we've never been able to eat them." He nodded. "But next time I'll do as you suggest."

And then, talking about the weather and shrimps and Southend, and what highly responsible work his was at Whitehall, and with what important Ministers of the Crown he was daily brought in contact, this courtly-mannered Mr. Worley quickly wormed himself into the complete confidence of Tom, and then gradually and very tactfully, he brought back the conversation again to Foulness Island.

"Of course," he said, shaking his head, "I know nothing as to how things are exactly done on the island, for as I've told you, I've only been once there and my duties, too, at Whitehall, lie all on the clerical side, still"—and he looked rather worried—"my chiefs often talk to me about what's going on and only this very week Lord Montgomery mentioned to me how afraid they are that one day some foreign power will get hold of a piece of this wonderful glass and then"—he turned out his hands—"the whole secret of its composition will become known."

"Oh, but I'm sure too many precautions are taken," said Tom, now quite at his ease. "They needn't worry there."

But Mr. Worley still looked worried. "Well, do you think now, Mr. Skelton," he asked earnestly, "that if one of the workmen on Foulness was offered a big bribe, say, of something like £10,000, that he would betray his country and smuggle out a sample?"

"He couldn't do it, sir," said Tom instantly. "He'd have no earthly chance." He laughed. "Why, we are all stripped mother-naked every evening before we leave the furnace chambers or any of the machine shops, and we couldn't get away with a piece as big as a pea if we wanted to!"

"But you might swallow a lump," urged Mr. Worley, "and make yourself sick afterwards and then hide the piece somewhere until you were coming home on leave."

Tom laughed again. "Nothing doing, sir," he said, shaking his head, "for the day before we are going on leave we are taken into the hospital and kept there 'under observation' as they call it, for thirty-six hours." He made a wry face, suggesting evil-tasting potions. "So there's no chance of carrying a piece off the island in that way."

Mr. Worley seemed impressed. "Then the precautions taken are most thorough," he remarked, raising his eyebrows.

"Couldn't have imagined there could be anything like them," nodded Tom. He looked aggrieved. "Why, your blooming soul's not your own when you're on that island, and they treat everyone of us as if we were spies." He went on, now throwing all his caution to the winds in the pleasure of enlightening the important gentleman from Whitehall. "You see, sir, the island itself is like a prison to anyone working on it, and that big compound that surrounds all the buildings where the glass is being made and used is like another prison, too—a prison within a prison—for we're never allowed to set foot outside it for twenty-eight days on end."

"Good gracious!" exclaimed Mr. Worley, "then don't you get any exercise or fresh air?"

"Oh, yes, the compound's a huge place and it must be more than a mile round, outside the fence. We get plenty of exercise and games, but we never see the sea, although it's not a quarter of a mile away, for the seawall hides it from us."

"And if any strangers managed to get on the island, say on a dark night," asked Mr. Worley, "could they get over into this compound, do you think?"

"They might," replied Tom, rather dubiously, "but the fence is high, and there are plenty of spikes at the top. Besides, there are lights every hundred yards and always armed sentries stationed about." He shook his head. "No, I don't think they could manage it, unless"—he hesitated a moment and considered—"unless they knew the place like one of us does and there was a good fog on." He nodded. "Yes, a fog would be their only chance. That'd help them certainly."

"And I should say you must get plenty of fog and mist there," suggested Mr. Worley, "with all those creeks and swamps on the land side of the island."

"Oh, we do," agreed Tom at once, "and they say it's awful in the winter, with the fogs hanging round for days and days at a time." He grinned. "But then if they did get into the compound they'd have a darned hard nut to crack to get into any of the shops. The only way to do it would be to get through the galvanized iron somewhere." He nodded confidently. "No, sir, I think we're pretty safe, for no stranger gets an opportunity to have a look over the place and make his preparations beforehand. The barbed-wire entanglements all round the island make it impossible for anyone to land. We've heard that if a bit of wire is cut anywhere there an alarm rings in the guard-room at once."

Mr. Worley looked very stern. "Well, there's one thing," he said sharply, "no one will ever get to know the special ingredients that we put in the mixture to give the glass its hardness and invisible properties."

"No, that they won't," agreed Tom emphatically, "for no one but the doctor and his assistant ever go into the mixing room, and three doors have to be unlocked every time for them to go there. Those two gentlemen are the only two on the island who know the secret."

Mr. Worley pursed up his lips. "Ah! but we have to be so careful, you see." He eyed Tom grimly. "But do you men never speculate as to exactly what is put in the sand?"

Tom laughed. "Of course we do," he replied. He spoke proudly. "We are all experts and picked men, the very best in England, and we used to think we knew everything about glass until we went on this job." He shrugged his shoulders. "Now we own up we're properly beat. It's a darned mystery to us."

A smile curved to Mr. Worley's lips and he took out his monocle and polished it vigorously with his handkerchief. "And they don't even let you know the name of the doctor, eh?" he asked looking rather amused. "You're not even allowed to learn who this doctor is?"

Tom shook his head. "No, he's just 'the Doctor' to everyone," he replied, "and his assistant they call 'the Chief.' But, as it happens, I know his Christian name," he added smilingly, "for one night when he was passing through the compound—they didn't know I was anywhere near—I heard the chief call him 'Ben.'"

"Of course, he's not a doctor who attends you in illness," informed Mr. Worley. "He's not that kind at all."

"Oh, I know that, sir, for if anyone gets hurt or burns himself they fetch one of the other doctors from the hospital. This one is a chemist-doctor, I've been told."

"And a most distinguished one," nodded Mr. Worley, "a great scientific man. I've lunched with him several times." He smiled. "But now would you say he looks what he is, Mr. Skelton? Would you call him a handsome and distinguished man?"

At once Tom's chubby face became all puckered up in fun. "With that carroty hair, sir," he chuckled, "tall and thin as a lamp-post, and long face with a hooked nose!" His eyes twinkled. "No, if I was a young lady I certainly shouldn't fall in love with him." He nodded. "But someone evidently did think him good-looking, because he's married, and they've just got a baby. He happened to be going home in the same plane that brought me on Friday night and I heard him talking about it to Colonel Maitland and say how curious he was to see the kid."

Mr. Worley laughed. "And where did they drop you this time, Mr. Skelton? Up Glasgow way?"

Tom laughed too. "No, not quite as bad as that, sir, but the car that brought us back to London was waiting for us in a whopping big aerodrome this time. They never tell us where they land us and we're not allowed to ask, but on Friday it was somewhere some miles beyond Newmarket, for I recognised that town as one we passed through. I think we went to that particular 'drome for the doctor's sake, because I heard him say as he stepped out of the plane that he would be home in less than half an hour. The car that took him was in front of us until we had passed Newmarket and then I lost sight of it."

For half an hour and longer the two talked on, and then at the end of that time there was very little that the engaging Mr. Worley did not know of the routine of the daily lives of those who worked on Foulness Island. But it did not seem to Tom that Mr. Worley was in any way prying, or had indeed, asked very many questions, the latter having from time to time just delicately diverted the conversation into those channels that were interesting him most, and had obtained all the information he wanted that way.

They parted at length the best of friends, with the whispered injunction however, from Mr. Worley that on no account must Tom mention to a soul that they had met.

"Of course, as you say, we really oughtn't to have talked as we have been doing," he smiled as they shook hands, "and if it got known we should both get a sharp rap on the knuckles. You understand?" And when Tom winked his eye, Mr. Worley smiled back with manifest amusement, as if they mutually were in possession of some very good joke.

THE following week, Scampy Rook, the proprietor of the small and wheezy motor launch, the 'Mary Belle,' that had just managed to pass the inspector, and was licensed to carry twelve passengers, was of opinion to the utmost of his convictions, that he had at last well and truly struck oil.

Scampy or Captain Rook as he preferred people to call him, was a big, burly man with a fierce, truculent-looking face and eyes set very close together. He sported a torpedo-shaped beard to suggest to his patrons that his appearance smacked of the Royal Navy, and for the same reason he wore a peaked cap with broad gold braid, and a closely buttoned reefer coat with big brass buttons.

Trade had been very bad, for the Southend summer season was waning fast and with all his hoarse importuning, "Here you are! One bob only! Cruise on the ocean deep!" passengers had been few, and he had often had to push off with only half of his full compliment.

But then all suddenly, from the big Palace Hotel had appeared this eccentric stranger, who wanted to be taken somewhere to fish in peace and quiet and was prepared to pay £4 a day for the exclusive use of the launch, with the services of Scampy included. Moreover, the hiring was not to be for one day only, but for several days, and indeed it might go on for a week if the weather continued fine. The hours of the fishing were to be from ten to five, the stranger agreeing to provide a daily luncheon hamper for them both.

Scampy had jumped at the offer and upon the morning following the afternoon when the bargain had been struck, exactly as the pier clock was striking the hour or ten, the stranger appeared on the pier steps, heavily laden with a large rug, a cushion, the usual fishing paraphanalia, and, to Scampy's joyful anticipation, quite a big luncheon basket from which protruded the necks of two bottles of beer.

"Now take me anywhere you like?" said the stranger affably, as he made himself comfortable and tucked the rug round his knees. "My name is Danker and I don't mind where we go as long as there's no crowd. Find a nice spot and anchor there, and if the fish are not biting, I'll read or go to sleep. My nerves are bad and it's sea air and quiet I want, much more than fish."

So Scampy, with an eye to the petrol consumption, just crossed over to the Nore Sand Buoy and, throwing out the anchor, prepared to earn the easiest money he had done for many a long day.

The fish were certainly not biting well, but Mr. Danker made no complaints, and, soon tiring, settled himself down in the stern and took a little nap. He was a stout man and was well insured against catching any chill by a big and heavy ulster that reached almost to his feet, and a big Trilby hat, pulled down low upon his forehead. His iron grey hair was very long at the back, and he was well bearded and moustached. His complexion was dark and he wore tinted glasses.

"A blooming foreigner," thought Scampy, eyeing him intently, "although you couldn't tell from the way he speaks. Looks like a musician to me. Now, I'd bet he plays the fiddle." He nodded curtly to himself. "But he'll have to cash up every night, whoever he is. There's going to be no tick or cheques over this job. It's going to be hard money, down."

Mr. Danker woke up presently and started to converse in a most friendly way about all sorts of things. He was very interested as to what channels the great liners took when they were steaming out to sea, of what significance were all the warning buoys and which sands were quite uncovered when the tide was low. He called Scampy 'Captain' many times, and foreigner or no foreigner, Scampy's estimation of him went soaring high, when the contents of the luncheon basket were revealed at one o'clock. Pork pies, beautifully cut sandwiches, bread and cheese, and not only the aforementioned bottles of beer, but two generous tots of good, strong rum to make everything sit easy on the stomach.

"Gosh! What a find!" ejaculated Scampy as exactly at two minutes past five he stowed away four one-pound notes in his back trouser pocket, after he had set his passenger upon the pier. "And his grub was real good, too." His big, cunning face took on an anxious expression. "I hope the blazes he turns up to-morrow!"

But Scampy need have had no fears, for Mr. Danker appeared again the next morning, with the same luggage and the same luncheon basket, heavily laden with good things.

"And where would you like to go this morning, sir?" asked Scampy, placing the basket in a secure place so that by no chance should any of its precious contents come to any harm.

"Anywhere you suggest, Captain," replied Mr. Danker cheerily, and then in an afterthought he added: "Oh, let's go round beyond Shoeburyness," and so by half-past eleven they dropped anchor just by the south-east Maplin buoy.

"And where are we now, Captain?" asked Mr Danker, who certainly seemed in a much less sleepy mood that morning.

"Just off the Maplin sands, sir," replied Scampy, "and if it were low water—except for the first couple of hundred yards—we'd be able to go dry shod, right up to dry land."

"Goodness gracious. All this long way!" exclaimed Mr. Danker. "Why, surely the shore's many miles from where we are now."

"Oh, Foulness Island!" said Mr. Danker, his eyes now opening very wide. "Then this is the secret island where all sorts of mysterious things are going on?"

"That's it, sir," nodded Scampy. "They are making wonderful bombs there, and, up to a couple of weeks back, it was boom—boom—boom—all day long. But I suppose they've got the things perfect now," he grinned, "and are keeping them for old Hitler or Mussolini."

"Foulness island!" said Mr. Danker very thoughtfully, "and only last night we were all talking about it in the lounge of my hotel after dinner. A very cocksure bookmaker from Birmingham, in a big way and very wealthy, I am told, was declaiming to us that it was such forbidden ground and so well guarded that he was prepared to bet any money no one could land on it at any time, day or night, under any pretence."

"Take it on, sir," laughed Scampy, "and I'll have a shot at it, if you make it worth my while."

Scampy spat with great emphasis into the sea. "No one knows who's on it, sir," he replied. "There may be fifty; there may be a couple of thousand"—he nodded darkly—"and yet never a soul is seen to approach or leave it. No boat ever goes near it, no cart or motor car ever goes over the sands at low water and it might be quite uninhabited, if we didn't know different."

Scampy spat again into the sea. "At night it's a blaze of light," he replied. "Big arc lights every couple of hundred yards all round it and then in the dark we hear the hum of the aeroplanes coming and going at all hours of the night. All the fetching and carrying is done with planes."

Scampy shrugged his shoulders. "No one knows and they take jolly good care no one shall know either. They're tremendously big and fast and they fly very high. They go away in all directions and sometimes they disappear right out to sea as if they were going to Belgium or France." He nodded. "But no one gets a good view of them, close up."

"Dear me! Dear me!" exclaimed Mr. Danker, evidently interested. He pointed in the direction of the island. "But what is there now to prevent you and me going right up to it and landing."

Scampy looked scornful. "Barbed wire entanglements, sir, fifty yards deep. There's only one narrow gateway on to the island, and they say that's guarded with a regiment of soldiers with machine guns."

"Very special bombs, sir," nodded Scampy again, "and no one will know anything about them until the next war comes."

"No; and if by accident any fishing boats get too close," said Scampy, "they fire right at them as a warning to sheer off, and if it's dark a huge searchlight instantly picks them out. They've always got someone on the look-out."

"But surely," protested Mr. Danker, "they don't sink those innocent fishing boats!"

Scampy laughed. "Oh, no, sir, they don't shoot to sink them, but they just pop bullets all round. One of my friends, a Mr. Snookes, swears that they fired through his sail one night and he's got the holes to show for it." His laugh changed to a scowl. "They're a high and mighty lot, these military, and think they can do just as they like. I've no time for them."

"Then someone ought to write to the newspapers about it and complain," smiled Mr. Danker. "That'd make them sit up."

"I've got a better idea than that," winned Scampy, "and with all their barbed-wire entanglements, I've often thought of making them look fools." He laughed scoffingly. "I could do it, if I wanted to."

"I'd wait for a foggy night," replied Scampy, lowering his voice darkly, "and then I'd come here in a rowing boat, with muffled oars. I'd bring some strips of stair carpet with me and a long clothes prop. I'd push one strip over the barbed wire as far as it would go, and then I'd climb on it to the end and push another strip before me." He looked very cunning. "See the idea, sir? With four or five lengths of carpet it would be as simple as A.B.C." He chuckled hoarsely. "I'd get on to the island and then I'd stick up a red flag in the ground somewhere, and—my oath!—wouldn't they look fools when the fog cleared?"

"It'd have to be a pretty thick fog, wouldn't it?" queried Mr. Danker, looking rather doubtful.

"Gosh!" exclaimed Scampy, "there'd be no trouble then. We get days and days of fog in the winter and it's so thick you can't see your hand." He spoke with great conviction. "Yes, fog's their deadly enemy, sir, and they can't fight against it."

Mr. Danker was very quiet that afternoon, and addressed few words to Scampy. He let the latter do all the fishing and sat huddled up in the stern either dozing or else staring out from half-closed eyes at the mysterious island he had just been hearing so much about.

Upon their return to Southend and when they were within a few hundred yards of the landing steps, he handed Scampy four Treasury notes, with the intimation that he should want the launch again upon the morrow. Then he remarked abruptly, "I take you to be a man of courage, Captain Rook." He spoke very sharply. "Is that so?"

For a moment Scampy looked surprised at the question, and then he nodded with a grim smile. "Afraid of nothing, sir, and been like that all my life. I was in the police once, and got discharged for striking a superior officer. Then I was runner for a street bookie for several years, and risked getting pinched a thousand times. Then I've worked a bit on the racing cars at Brooklands, and was in danger of my blooming life every blessed day." His smile became more pleasant. "Yes, I've always been a bit of a tough."

"Good!" commented Mr. Danker. "Then I may have something to say to you to-morrow. Perhaps I'll put you to the test."

CHAPTER IV
THE SECRETS OF FOULNESS

THE third day or the hiring of the Mary Belle by the eccentric Mr. Danker had proceeded very much upon the same lines as the other two had done until the luncheon basket had been emptied. They had anchored again off the south-east Maplin buoy. Mr. Danker had fished a little, dozed a little, and carried on a desultory conversation with his companion. Notwithstanding that the weather was quite warm for the time of year, he had discarded none of his garments, and the long ulster still enveloped his stout figure.

Scampy, hoping from the parting remark of his generous patron the previous evening, that more emoluments yet might be upon their way, was very disappointed that no reference was again made to the matter of his courage. However, another very satisfactory lunch having been disposed of, and the last drop of rum being well and truly drained, his hopes went soaring high when Mr. Danker said suddenly—

"Well, Captain, if you really are the man of courage that you told me you were, I have a nice little job for you that may mean quite a bit of money." He smiled. "Now, you still say you are a plucky fellow?"

"Go anywhere," grinned Scampy, "do anything"—his eyes narrowed, and he nodded significantly—"if I'm well paid for it."

"Good!" exclaimed Mr. Danker, "then I want you to get on to Foulness Island tonight."

Scampy started and then looked quickly up at the sky. "But there'll be no fog with this weather," he said with a shake of his head. "More likely a bit of a storm." He nodded. "You mean that carpet business, do you?"

"No, no," replied Mr. Danker sharply. "Nothing so difficult as that! A much simpler way!" He eyed Scampy as if he were trying to mesmerise him. "This launch is going to break down off the Maplin light tonight, and you'll drift on, or be blown straight on to the island. The tide'll be just right."

"No! No!" exclaimed Scampy with a frown, "but that doesn't sound too good. I don't like the——"

"One moment," interrupted Mr. Danker. "I want to know a few things about you first. Now, are you a married man?"

"Well, do you make much out of this launch? Does it return you a good livelihood?"

"By hell, no," swore Scampy instantly, and in great disgust. "This damned engine simply drinks petrol, and there's always money going out in repairs. If I'm carrying more than two passengers I have to employ an extra hand, too, and his wages take away any profit there might be." He shrugged his shoulders. "No. I just pay expenses in the summer, and in the winter I run into debt. I'd chuck it any day if I could."

"I can't," replied Scampy. "It's capital I want, and I haven't got it." He spoke disgustedly. "Why, this very week I'm missing the best of chances and I'm quite helpless and can do nothing. A friend of mine has one of the tightest little pubs in all the country and he's got to sell it because of his health. It's in Battlebridge, not ten miles from here, and he's giving me the first offer, if I can raise the cash." He laughed scornfully. "It would be easier for me to raise the devil."

"All right, then," said Mr. Danker decisively. "You can take it to-morrow. I'll lend you £300 and there'll be no question of any paying back, if you just do as I want you to."

Scampy could hardly get his breath. "And you'll do this," he gasped, "just for me getting on to Foulness?" He suddenly became suspicious. "Is it spying you're after? Is it a hanging job if I get caught?"

Mr. Danker threw his head back and laughed merrily. "No, no, my friend, it's nothing like that," he replied in great amusement. "It's just a bet I've taken with that rich bookmaker and I want to win it, because he's always so cocksure about everything. He's betted me £500 to £25 that I can't prove to him that civilians have landed upon Foulness Island without any difficulty. He's given me ten days to win the bet, but this morning I found I must get back to London the day after to-morrow, and so if I'm to win it I must win it straightaway, as I can't stop here any longer." He began to laugh again. "Spying! Why, I'm the proprietor of a great London newspaper. I own the 'Daily Telephone!'"

Scampy's heart was thumping hard. "And what exactly do you want me to do?" he asked hoarsely.

Mr. Danker spoke impressively. "Now listen carefully," he replied. "I've thought it all out." He broke off suddenly. "By the bye, is this launch insured?"

"For £75," nodded Scampy. "That's all I could get on it"—he grinned cunningly—"or anything might have happened."

"And it's all it's worth," commented Mr. Danker with emphasis. "That engine is very crook and would never have lasted you another season. I've been expecting every day that it would break down." He went on—"Well, this is what I want you to do, and, as I say, the tide's just right for it. Tonight at half-past seven you'll be at the end of the pier, calling for passengers for a moonlight trip round the Maplin light, then you'll go——"

"But supposing I don't get any passengers?" interrupted Scampy. "They don't always swallow the bait, you know!"

Mr. Danker looked annoyed at the interruption. "But you'll make the fare so low," he frowned, "that you'll be certain to get them. Take them for a shilling, or even for less if they won't pay that. Make the offer look tempting, and say the cruise will last a couple of hours."

Scampy eyed him narrowly. "You'll be coming, of course?" he asked. "You'll be seeing me through with it?"

Mr. Danker shook his head. "No, no, I want my proper hours of sleep," he replied instantly. "I'm too old for such adventures now." He spoke quickly. "But there'll be no danger or difficulty, man. It'll be a very simple little affair for you to do."

Scampy looked doubtful, but the thought of the £300 spurred him on. "And what'll come next," he asked, "supposing I do get a boat load?"

"You'll go out as far as the Maplin Light and then, just turning for home, you'll tell them the engine's not going properly and you'll start fiddling about with it until you finally make it stop altogether. Then you'll say the platinum point must be dirty and you'll go at it with a file until there's no platinum left. Then you'll call out it's quite hopeless, and you'll have to let the launch drift with the rising tide right up to the island. Then——"

"But why don't I throw out my anchor?" growled Scampy in a tone that showed he was not at all taken with the idea. "They will be asking me that at once."

"What for?" asked Mr. Danker with some irritation. "What good would that be? You couldn't remain there all night. Think of your passengers. The exposure would be dreadful for them! No, no, you'll drift on until the launch grounds. Then you all jump out and make for the shore as quick as you can before the tide overtakes you. You must manage it so that you'll be close in to the shore. Then you must wave your lantern frantically and you'll lead the shouting as if you were very much afraid."

"Nonsense!" exclaimed Mr. Danker testily. "They'll see you're only excursionists, and common humanity will compel them to give you all the help they can." He shrugged his shoulders. "Why, if there's any wind about, you may all be soaking wet by then, and there may be children in your party, and girls in light clothes. They'll have to take you up on to the island and get you dry clothes and hot things to drink. You'll probably stay the night then, or they'll ring up for a plane to come and fetch you from Southend."

"They wouldn't use any of the planes they've got there," grunted Scampy. "That's a certainly, for they never let any one see them." He looked up sharply. "But I say, Mister, I see a snag in this, for even if I bring it all off as you say, what about that bookmaker friend of yours giving the whole show away and telling everyone it was all a put-up job, done for a bet." He whistled. "A nice thing it'd be for me, wouldn't it? Why I should get two years' hard labor, at least."

"Oh! Captain, Captain," said Mr. Danker reproachfully, "how can you be so simple?" He looked scornful. "Just as if I should take him or a living soul into my confidence! Why, I should get punished as severely as you, or probably more so, because I had paid you money to do it!" He shook his head emphatically. "No, of course, my bookmaker friend will know nothing about it, and it will be just a very wonderful coincidence that all this happened to save me attempting any adventure on my own." He bent forward confidingly. "Don't you see you are quite safe?"

But Scampy made no answer, and, turning his eyes away, stared thoughtfully into vacancy.

"I don't see any difficulty at all," went on Mr. Danker persuasively. "No one can possibly have any suspicion of you, for there'll be the faulty magneto to show what's gone wrong."

"You'll get the money," interrupted Mr. Danker, with a laugh. "Oh, that will be quite safe, for you'll have half of it straight away. Here, I'll give it you now," and thrusting his hand into his vest pocket, he produced a bulky wallet.

Scampy moistened his lips and swallowed hard as he watched him peel off note after note from a thick wad, and then he hesitated no longer.

"All right, Governor," he said hoarsely. "I'm your man. I told you I was a good plucked 'un." A thought seemed suddenly to strike him, and he added. "But here, I say, when do I get the other half?"

"I'll come and give it to you," replied Mr. Danker—he hesitated—"or else I'll post it you if you give me your address." He nodded. "You can depend upon it, for I am a man of honor, and besides, I've told you who I am."

They parted at the pier steps, and then when Scampy was lashing the Mary Belle to her moorings, he noticed a small piece or paper close by where Mr. Danker had been sitting. Picking it up curiously he saw it was it was a Liverpool street station cloak-room ticket, dated the previous week, and made out for a bag deposited there by a J. Reynolds.

"Hum!" he remarked, "that's funny!" He frowned thoughtfully. "Now, I wonder which one of them is his real name?"

That evening at half-past seven the Mary Belle was being held close to the pier steps with a large boat-hook, and Scampy was looking up and shouting to a little crowd of people who were leaning over the rail above—"Here you are! Great moonlight cruise round the famous Maplin Light! Only a bob a head. Come on now, for there are only a few seats unreserved."

It was a rather warm night for the end of September, and there was a suggestion of thunder in the air, but the sea was not choppy, although there was certainly a bit of a swell.

Scampy's assistant, an oily-looking young fellow in dirty overalls, joined in with the exhortation. "Come on ladies and gents," he cried. "We'll be just in time to see the great liners going out to sea. They'll be passing in half an hour."

A hundred and more people, men, women and children, had got their heads over the rail, eyeing the little launch with interest, but with apparently no inclination to invest their shillings. A young fellow about twenty, with a pretty girl upon his arm, started playing the Volga Boatman Song upon a concertina, and, playing very nicely, the attention of the crowd was diverted and fewer people leaned over the rail. A toothless, but very happy looking old man applauded vigorously when the tune was finished, and importuned the musician to go on.

Time was slipping away, it was 20 minutes to eight, and Scampy began to get desperate.

"Here you are, then," he shouted hoarsely. "A tanner and a threp and you make the cruise! Only ninepence for two hours on the ocean deep! Come on now!"

The toothless old man leaned over the rail. "What! two hours for ninepence!" he shouted down to Scampy. "All right, then, I'll come." He turned to the young man with the concertina. "You play very nicely, sir, and if you promise to give us some more tunes, I'll very willingly pay for you to come"—he looked amused—"on the great moonlight cruise."

The young man appeared gratified. "But I've a young lady with me," he said, indicating the pretty girl.

"And bring her with you," said the old man heartily. "Your music will be worth more than eighteen pence to me."

So the three at once took their seats in the launch, and example being infectious, in less than five minutes, every place was filled and the little vessel was pushing away from the pier to the tune of Auld Lang Syne upon the concertina.

The passengers consisted of the old man, two young fellows and their girls, two mothers with two small boys, and a middle-aged woman by herself, a stout florid man who looked like a holidaying publican, and a man of scholarly appearance who might have been a schoolmaster.

They were a happy, merry party as the launch chugged along, all except Scampy, who was attending to the rattling engine and he kept looking over his shoulder towards a bank of dark cloud that had begun to creep slowly up over the Kentish coast.

"Blast it!" he muttered. "If I'd got a glass here I'd swear it would be falling like the very devil. There's a storm coming. I'll stake my blooming life."

But the dark bank of cloud was as yet only very small, and no one in the boat had apparently noticed it. The concertina was reeling out melody after melody, and all were joining in who could, when there were any choruses to be sung.

They rounded the Maplin Light with out mishap, and by then night had fallen. A hazy moon, at half full, had just risen, but the rapidly approaching bank of clouds was threatening every minute to obscure it. Suddenly there came a puff of wind, and the oily sea became stirred into little waves. Another puff followed, and this time it was more sustained. The waves became bigger and spray began to fleck over the side of the launch. The women with the little boys looked uneasy, but Scampy reassured them at once.

"It's nothing but a capful of wind, ladies and gents," he called out happily, "and if it's going to rain, we'll be home long before it starts."

But misfortune was in store, for suddenly Scampy darted to the engine and switched it off. "Two cylinders missing," he announced, "but I'll have it right in a jiffy. Don't anyone be worried," and pulling a small greasy-looking bag from under one of the seats he took out some tools and began fiddling about to find out what was occasioning the trouble.

The wind was freshening every moment now, and the Mary Belle began to roll and bump unpleasantly in the troughs of the waves. The little boys began to cry and one of them was sick. The women looked very frightened, but the men put on bold fronts, and the young one with the concertina took out and lighted a cigarette. The rolling, however, became more and more pronounced and the spray began to wet everyone. Scampy was huddled over the magneto and wording desperately with a file.

Suddenly then, one of the women shrieked. "Oh, how were drifting! That buoy we were near when you stopped must be miles away now!"

"It's quite all right, I tell you, lady," shouted Scampy with some effort to make his voice heard above the noise of the wind and the banging of the waves. "Don't get worrying now, for I'll soon have her going again."

"But I say, Captain," called out the man who looked like a schoolmaster. "Hadn't we better anchor? This drifting broadside on seems very dangerous to me!"

"It's not dangerous," shouted back Scampy, "if you keep still and don't upset the balance of the boat. I can't anchor here, and we'll be much safer nearer the shore. We'll be over shallow water in a couple of minutes and there'll be no swell there."

But very soon the attitude of the majority of the passengers became one of panic, and with every bump of the waves they clung frantically to one another fearing the launch was going to be swamped. To add to their terror Scampy now abandoned all pretence that he thought he could make the engine start, and joined with his assistant in bailing desperately with two pannikins that had evidently been provided for such an emergency.

Alone of all the passengers, the three elder men kept their heads and the stout and florid-looking one awoke to speech and took command at once, as a born leader of men.

"All sway with the launch," he bawled in a voice like a bull's, "and don't shift from your seats however much she rolls. I know this coast well, and although we're a hell of a way from shore, we shall soon ground in a couple of feet of water, and then we can run over the sands on to the island. This is Foulness we're drifting on to."

And the toothless old man supported him valiantly. "Never mind the rain, anyone," he shouted as big drops began to splatter the already soaked passengers, "for the harder it comes the better. It'll beat the waves down."

Then suddenly a great blinding light stabbed the darkness. It swept round in a majestic arc and then, picking up the launch, remained focussed upon it.

"Hoorah!" shouted the florid man, "they've seen us on the shore and now were all as safe as if we were sleeping in our beds."

The launch swept forward, with the force of half a gale behind it, along the silvered path cast by the search light, and a couple of minutes later Scampy threw down his pannikin and darted for a large boat-hook.

"We're grounding; be ready to jump out," he shouted, and driving the boat's hook down viciously over the side of the launch, the bow swung round and pointed straight towards the shore.

Bump—bump—bump went the launch and almost in one movement Scampy and the florid man had jumped overboard and were tugging at the stern to prevent the little vessel turning sideways again.

"Now out with you all," bellowed Scampy. "Quick, quick! We'll not be able to hold her long," and so in less than a minute all the passengers, soaked and bedraggled, but most devoutly thankful, were scuttling for the hard uncovered sand that the friendly search-light was picking out for them.

Scampy, as became all glorious maritime tradition, was the last to leave the launch, after having with one hand thrown out the anchor, and with the other grabbed up his little bag of tools.

"But we must still be quick!" shouted the florid man, as shaking and sobbing in their relief the little crowd of passengers were now seemingly content to remain where they stood. "We must be quick, I say, for it looks as if we've got a couple of miles yet to go, and with this wind behind it the tide'll come up devilish fast. Come on, make for that search-light. I'll carry one of the kids."

In the meantime, telephones had been buzzing furiously upon the island, the guard had turned out, and a highly interesting hand of bridge been cut short in the officers' mess. So when the little band of excursionists, with the crew and captain of the Mary Belle bringing up the rear, appeared at the big gate to the one opening in the barbed-wire entanglements, they were met with what appeared to their dazzled eyes to be a whole regiment of soldiers, with a tall aristocratic looking officer standing at their head.

"Keep back," roared the sergeant of the guard as they made to shuffle unceremoniously through the gate. "Wait and do as you are told."

"Let them through, sergeant," said the officer, in a finely modulated voice. "They don't look very formidable to me." He glanced from one to the other of the little crowd, and then asked sympathetically. "Who are you, and who's in charge?"

Scampy stepped forward with importance. "Me, sir," he said. "Captain Rook of the motor launch Mary Belle, of Southend, licensed to carry twelve passengers. They're all here. Our engine broke down and we've been driven on shore." He shook himself dismally. "We're all soaking wet through, sir."

"So I perceive," smiled the officer. He turned to a younger man behind him. "Take the ladies and the little boys at once into the infirmary, please, Mr. Rainey, and tell Matron to do what she can for them in the way of clothes." He turned to the sergeant. "Take these gentlemen into the guard room. I'll be there in a minute. I want to speak to them."

The seven men were led away into a room close by, and Scampy started at once to wring the water from his clothes.

"Here you stop that," roared the sergeant, very red in the face. "Wait until you're outside again."

Scampy regarded him scowlingly. "I was in the Metropolitan Police Force once," he commented gruffly, "and I got kicked out for knocking down my superior officer." He paused significantly. "He was a sergeant, too."

Whatever remark the furious sergeant was about to make died on his lips, for at that moment the pleasant-speaking officer entered the room.

"This island is a Government reserve," said the latter at once, "and I am the commanding officer here. I shall have to ask you a few questions." He made a gesture to the sergeant, who bottled his wrath with a great effort, produced a sheet of foolscap paper from a drawer and made ready to write the answers down.

"Well, are you all British subjects?" asked the officer. "Good! then now give me your names, addresses and occupations, please." He looked at Scampy. "I'll take you first."

"John Ebenezer Rook," said Scampy, "captain of motor launch, Mary Belle, and of 21 Peele street, Southend. Born in Hoxton, 38 years ago."

And then each in turn told of himself. The two young men, it appeared, worked in the City, one was a clerk and the other behind the counter in a haberdasher's shop; the scholarly-looking man was a butcher in the Mile End road; the florid-faced one was the verger of St. Michael's Church in Stepney; and the toothless old man worked at a tailor's in Houndsditch. They were all trippers to Southend, and produced the return halves of their tickets in evidence.

The officer seemed quite satisfied, and so, in a few minutes, all seven of the shipwrecked men, in varying stages of nakedness, were drying their soaked clothes before a roaring fire in a small ward of the island infirmary, and fitting themselves out in sundry garments that had been lent to them.

Steaming cups of coffee and thick ham sandwiches were brought in, and they were informed that the women of the party were likewise being cared for.

A young officer attended by an orderly came in presently and told them they were to remain for the night, and that the following morning about eight o'clock an aeroplane would pick them up on the sands and return them to Southend. He added most politely that he was sorry to tell Captain Rook his motor launch was now a total wreck. Its anchor had dragged, and the little vessel had been dashed to pieces against the seawall.

Scampy tried his hardest to look very glum, but inwardly he was chortling with joy. That would mean another £75, and added to the £150 he had stowed away behind the kitchen sink at home, he thought he had done very well, even if he did not get a penny piece more.

"Never mind," he said with a gesture of manly resignation. "I've saved my passengers, and that's the main thing."

"Bravo!" exclaimed the toothless old tailor with enthusiasm. "That's the true old sea-dog spirit that has made our country great."

"One thing," grinned Scampy when the chorus of approval had subsided. "I've salvaged something, for I've saved my bag of tools," and he pointed to the oily-looking bag that he had never let out of his hands until he had come into the ward.

The officers left them and the orderly, ascertaining they were needing nothing more, also bade them good night.

"You'll be locked in, gents," he said in parting. "It's the colonel's orders, because as you know you really oughtn't to be here," and he pulled the door to and they heard the lock click.

Then to everyone's surprise they saw that Scampy's oily bag held more than dirty tools, for he produced from it a full bottle of whisky, and the spirit was promptly divided among them all, to insure as the generous donor put it, the soothing of their nerves. Then another surprise followed, for the old tailor, with a gleeful chuckle, tugged out from one of his overcoat pockets a pint of strong navy rum and insisted that everyone should share and share alike.

So, shortly after midnight, it was a thoroughly sleepy and slightly befuddled lot that betook themselves to their beds, and very speedily the potency of the ardent spirits they had imbibed was evidenced by their deep and heavy breathing.

An hour passed, nearly two, and the light from the fire flickered and grew dim, so dim that when a stealthy figure slipped ghost-like from one of the beds it almost cast no shadow. Whoever he was the figure moved with the stealthiness of a panther and the keenest ears could have detected no sound as he crept across the room.

From the coats drying before the fire he selected a dark one, and then he went quickly over to Scampy's bag of tools and, flashing the smallest of torches, opened it noiselessly, and after a few moments' search abstracted a little screw-driver.

Then he tip-toed over to the locked door of the ward and kneeling down, swiftly, and taking extreme care that he made no sound, proceeded to remove the four screws that held the bolt housing of the lock to the frame of the door-way.

The door swung ajar, and for a long minute he crouched, staring down the dark passage that stretched away before him. All was silent except for the sighing of the wind and the distant moaning of the sea. The storm had almost died down and he could see from a small skylight that a fitful moon was showing.

Satisfied apparently at last that there was no one about, he placed the part of the lock he had removed in a corner where he could easily find it again, and after a moment's hesitation, pocketed the four screws. Then the darkness of the passage swallowed him up.

Two hours and longer passed before he returned, and then he darted into the ward like a hunted creature. He was panting heavily, his heart was thumping like a piston, and he was covered in a cold sweat. One of his hands was sticky with blood. He pulled the door to like lightning and without flashing his torch groped for and found the bolt housing. Then with feverish haste, and with hands that shook, he started to replace the four screws. To his consternation, however, he found that he had only got two of them and that the other two must have fallen out of his pocket. But he gave no time to his dismay, and, his hands steadying, he screwed on the housing as best he could.

Then it might almost have seemed that his intentions were sinister ones, for, creeping from bed to bed, he stared hard, one by one, into all the faces of the sleepers. But they were all in dead slumber, and he turned away. Next he took off the jacket he had been wearing, and, spreading it out upon the floor, went over it every inch with his little torch. One small spot appeared to occasion him considerable anxiety, and he dabbed at it many times with water that he carried over in a tumbler that he took off one of the water bottles.

Then he returned the jacket from where he had taken it, and with one of his socks most carefully rubbed over all parts of the lock and the door where it was possible he might have left a finger mark.

Finally he crept back into his bed, and closing his eyes, tried resolutely to fall asleep, but for many many minutes his ears were straining for a sudden shout outside, and it was not until dawn was just breaking that he sank into a troubled doze.

At seven o'clock the door of the ward was opened noisily, and flung back with a loud bang. Biscuits and cups of steaming coffee were brought in. Everyone was told to get ready quickly for the aeroplane would be upon the sands in a few minutes.

It was a fine morning, and the little party, now joined by the women and the two small boys, were escorted by two soldiers through the opening in the barbed wire entanglements. They were all in high spirits, and Scampy had a hard job to pull a glum face when they passed by all that remained of the Mary Belle. He would have liked to have stopped for a few moments, but the plane was waiting for them, and they were hurried away.

The journey was a very short one, and landing in the aerodrome at Southend they all shook hands vigorously with one another, and dispersed in different ways.

Half an hour later the telephone from Foulness started to ring furiously, and the Southend police were being frantically enjoined to get in touch with and hold every one of the party who had been sheltered on the island the previous night.

A sentry had been murdered and his body had been found hidden under a tarpaulin, covering over some bags of cement! He had been stabbed with his own bayonet through the heart!

CHAPTER V
LAROSE TAKES UP THE TRAIL

A FEW days after the wrecking of the Mary Belle, Gilbert Larose, the one time international detective, now a country squire and married to the beautiful and wealthy widow, who up to the time of her marriage with him had been Lady Helen Ardane, was sitting with three companions in the big lounge of his home at Carmel Abbey.

It was the hour before dinner, the evening was chilly, and a huge log-fire was burning in the enormous grate.

All four men were comfortably tired after a long day with the pheasants. There had been a goodly number of guns at the shoot, but the others participating in it had just made their good-byes and gone off in their cars and only the three, now with their host, were staying the night at the Abbey.

One of them was Sir Herbert Carnaby, with courtly and old-world manners, a second was the aristocratic Colonel Bevan, of the Air Force, and the third was a quiet-looking little man, plain Mr. Grant, whose occupation, if he had any, no one apparently knew. This last man was about fifty years of age, and Larose had met him for the first time the previous night, when he had come down with Sir Herbert.

"A most delightful day," remarked Sir Herbert, "and probably we had some of the finest shots in the kingdom among us. The shooting of Major Turnbill was magnificent, and the way he brought down those two last birds is a thing to remember. I never thought he'd get either of them; they came over so fast and so high."

"And Lord Banting!" supplemented Colonel Bevan. "A fine workman and never anything ragged about his shots, ready to the hundredth part of the second!"

Gilbert Larose shook his head and made a wry face. "But I think, gentleman," he said judicially, "that, although we mayn't exactly like to admit it, a foreigner beat us all, for no one quite came up to Herr Mitter. He never missed his bird all day, and dropped every one with the precision of a machine. He got a right and left by that last coppice with perfectly magnificent shots, when I would have sworn he had purposely given them too much law and let them get clean away. My head-keeper thinks he's a marvel!"

A short silence followed, and then Sir Herbert asked carelessly. "And is the Herr a great friend of yours, Mr. Larose? Do you know him well?"

"Yes," nodded Larose, "I know him quite well"—he hesitated—"but, no-o he's not exactly a great friend, although I certainly see a lot of him. I often go to his place at Dunwich, for we have antiquarian tastes in common, and part of the cloister of an age-old Franciscan priory forms two of the walls of his house. Still"—he hesitated again—"I couldn't say we were great friends, for I really don't understand him well enough."

It was now Sir Herbert's turn to hesitate. "Well, as you say you see him often," he remarked after a short pause, "and it happens we were discussing him just before you joined us now. Will you sum up his character for us as far as you can determine it?" he made an apologetic gesture. "That is, of course, if you don't mind dissecting one of your friends."

"Certainly, I don't mind," replied Larose with a smile, "for, as a matter of fact, although as I say, I know him quite well in some ways, I am yet as curious about him as, apparently, are you."

He thought for a moment and then spoke very slowly. "Herr Mitter is a very capable and resourceful man. He wishes to give everyone the impression that he is most casual and easy-going, but in reality he is nothing of the kind. He is very purposeful, very determined, and everything he does he does well. He is a gentleman, but all the same I wouldn't like him as an enemy, for he could be perfectly relentless and have no pity at all."

Sir Herbert nodded as if he quite understood. "Certainly, a very interesting personality!" he remarked. He indicated his two companions. "We have, none of us, of course, met him before today, but like you, we are of the opinion he is a man of strong character." He looked intently at Larose. "But I gather from what he was telling us all at luncheon that his great passion in life is painting."

"'Yes, and he's a real artist there," replied Larose. "He paints as well as he shoots." He smiled. "As I say, he'd be something of a master in whatsoever he took up."

That night at dinner Sir Herbert Carnaby said banteringly to his hostess. "And has your husband quite settled down, Mrs. Larose? Is he quite resigned now to the humdrum of country life, after all his exciting adventures in the underworld?"

The beautiful face of Helen Larose clouded, and she shook her head with a pretence of great sorrow.

"No, he isn't," she replied quickly. "He's not resigned to it at all, and he'd much rather blacken his face and go hobnobbing with criminals in the East End than stay here with me."

Sir Herbert appeared to be very shocked. "Good heavens!" he exclaimed, "then if that's the case, you ought to let him go at once, and find consolation elsewhere." He gave a little cough. "I won't mention any names, but I know several who would gladly take his place, and they are not far away either."

"Thank you, Sir Herbert," laughed Mrs. Larose. "I may be asking you for their names much sooner than you might expect." She looked most disapprovingly at her husband. "If they hadn't found that Hoxton murderer last week I'm sure I might have awakened any morning and found I was alone!"

"No, no," laughed Larose, "no more common and vulgar murderers for me, Helen. I'd want to go after someone who'd hit back. That's where the thrill comes in." He turned to the others at the table and went on reminiscently. "Years ago, I once trailed a man to the dark passage of an untenanted house, in the dead of night, and I always regard that as, perhaps, the most thrilling experience of my whole life. He was a desperate man, and wanted for murder; we were both armed, and we each knew the other was there, but neither of us dared move lest the slightest sound should betray our position for the bullet. So there we both crouched, knowing that from between three and four hours must elapse before the faintest light would come from a small window and then, it would mean death for one or the other of us." He frowned and shook his head. "I cannot describe the horrible feeling, and yet there was a sort of dreadful joy in it, as when a gambler is staking everything upon one single throw of the dice."

Larose laughed. "Oh! very tamely. The other chap went to sleep and I was able to get his gun and handcuff him before he was properly awake. I had been crouching down, however, it must have been for about two hours, and then, to my amazement, I heard a gentle snore. I couldn't believe at first that he had really gone to sleep, and thought it was just a trap. But the snoring went on and became louder and so I started to creep in his direction. I touched his body and then felt up for his pistol hand. The rest was child's play, and he hadn't time to utter a word before it was all over."

"Poor fellow," exclaimed one of the ladies present. "And was he hanged afterwards?"

"Oh, no," replied Larose, "he was acquitted at the trial. He put up the weakest alibi I have ever heard, but it happened, as we found out afterwards, there was a life-long enemy of the dead man upon the jury and, a very plausible fellow, this chap persuaded the others to let him off. It was a quarrel over a girl, and she was very pretty and gave evidence for my snoring friend. He married her later on, and he's quite a respectable member of the community now."

"Oh! wasn't he?" laughed Larose again. "He came to see me afterwards and practically admitted it. He was quite a pleasant fellow, and very curious to learn how I'd found out that he'd fallen asleep that night. He never knew he snored!"

Later on, when after two hands of bridge and some music the ladies had gone up to bed, and the four men were together over a last cigarette before the library fire, Sir Herbert leant down and whispered something to Mr. Grant and then turned with a decisive movement to Larose.

"Look here, Mr. Larose," he said impressively. "We know we can trust you and we think you can do us a great service. It's about that Herr Mitter, and if you often go to his place, tell us what sort of people do you meet there?"

"Well, has he many visitors, and if so, do you, among them, meet many army and navy men, or officers connected with the air-force?"

"Most certainly I do," replied Larose, "and he seems very popular among all the three services." He nodded. "And I don't wonder at it, for he's very hospitable and keeps open house for all his friends. He has a first-class cook and the best of wines. His hock, by the bye, must be about the finest vintage in the world." He smiled. "Also there are always plenty of pretty girls coming out in their cars to see the Herr. It's just a nice little drive from both Colchester and Ipswich."

There was a moment's silence and then Sir Herbert said sharply. "Now we shall be very much beholden to you if you will tell us all you can about this gentleman, for to put it bluntly"—he looked grimly at Larose—"this Herr Mitter of yours is a spy."

Larose gasped incredulously. "What!" he exclaimed. "Mitter a spy! Surely it can't be so!"

"But it is, right enough," nodded Sir Herbert sternly, "and we have been aware of it for a long time now. He is in the Secret Service of his country, and his place in Dunwich is the clearing-house for reports that are forwarded by his agents from all parts of the kingdom."

"Well, well!" went on Larose, still appearing as if unable to credit the statement, "and yet he seems so friendly disposed towards us! He's always saying how he loves the country and how kind everyone is to him!"

"I daresay," sniffed Sir Herbert contemptuously. "No doubt he is a fine actor." He continued. "Now, we want you——"

"One moment, please, Sir Herbert," interrupted Colonel Bevan quickly. "We'd better introduce Grant properly, first." He turned to Larose. "Mr. Grant here is the head of the C. department of our Secret Service, and is responsible for all the counter-espionage in this country."

"Whew!" whistled Larose, regarding the little man with great interest. "The mysterious recluse of Whitehall, whose anonymity is so jealously preserved." He bowed towards Mr. Grant. "Of course I have heard of the wonderful work your department does, sir, and I am sure it is an honor to be trusted and be told whom you are."

Mr. Grant smilingly acknowledged the compliment. "We are certain we are running no risks in taking you into our confidence, Mr. Larose," he said, "and, indeed I regard it as a most fortunate happening that Sir Herbert brought me down here yesterday."

"Because, having met this Herr Mitter," was the reply, "we have formed quite a new estimation of his character. We are convinced now he is anything but the third-rate Secret Service agent his correspondence and telephone calls have been leading us to believe." Mr. Grant frowned. "Yes, we have been well bluffed there, for probably we have not been finding out one quarter of what he is doing." He shook his head. "He looks dangerous, very dangerous, and it may now turn out, too, he is the very man we have been trying to uncover for many a long day, the master spirit of them all."

"Good gracious, but what on earth can you have found out about him today?" asked Larose, looking more puzzled still. "You have only been in his company such a short time and you can have had very little opportunity for conversation with him."

"No, but having been brought face to face with him as we were for the first time this morning, we are most profoundly and unpleasantly impressed with his strength of personality, and we realise how we have been under-estimating him. We are now convinced the paltry little items of information that from time to time he mails abroad cannot possibly represent the sum total of his activities over here. He must be playing a much deeper game."

"But I think you must add, Grant," said Sir Herbert quickly, "that those two discoveries of last week had in part prepared us for this change in our ideas."

"Quite so," agreed Mr. Grant, "for they certainly did suggest that we were under-estimating him." He turned to Larose. "It's a long story, but I will make it very short." He spoke impressively. "Now for nearly two years we have been rendered most uneasy by the extent to which information of what we are doing has been reaching a certain country. Our own agents there have been continually reporting to us a knowledge by the authorities of things and happenings that we believed to be among our most closely guarded secrets. To mention only a few—they have come to know all about our new type of torpedoes; they are copying our new fuses, and certain special modifications in our aeroplanes are being adopted by them, too." He shook his head vexatiously. "It has been as if some master mind were directing an organisation over here, and with such success that few of our secrets remained secrets very long."

Larose looked most concerned. "Then they have learned about that invisible glass!" he exclaimed quickly.

"No, no," replied Mr. Grant. "So far we have been able to baulk them there, although we are certain they are now making that their special objective," he nodded significantly—"and are unhappily getting very close, too. Indeed we are reluctantly forced to the conclusion that they have learnt somehow where it is being made, for we believe that within the last few days, a most daring attempt has been made to get hold of some of the material."

He continued. "But to return to Herr Mitter. Just about a year ago, a foreigner who was double-crossing his own people and working for us, a man by name of Lieder reported that a Herr Mitter of Dunwich Hall was mixed up in an espionage organisation here, in our midst, and that he, Lieder, had been ordered by his people to get in touch with him and work under him in spying over here. Then to our great dismay, within a few days of having given us this information, this Lieder disappeared, and we have heard nothing more of him since. He vanished, too, under very sinister circumstances, for we know he was going down to Dunwich, and we always wonder if Mitter had been warned he was in our employ, and in some way managed to make away with him."

"But you don't know this man actually visited the Herr?" asked Larose with a frown.

"No, we can't be certain there, for at that time we were not watching Mitter as closely as we are now. We have since taken Mitter's butler, an ex-army man, into our service, but he unhappily does not remember if anyone answering to Lieder's description came down to Dunwich, for then he was not interested in any of Mitter's visitors and he says, as you do, that there have always been a lot of people calling there."

"This butler's not too intelligent," supplemented Colonel Bevan, "and the information he has supplied has been of no real value. He says he has to attend to Mitter's two cars and is a lot in the garage in consequence. Also, he is always being sent on errands and misses a lot of the visitors in that way."

"And have you had Mitter shadowed when he goes away from Dunwich?" asked Larose.

"Not to any extent," replied Mr. Grant, "for we haven't dared to. We have been very careful not to arouse in him any ideas that he is under observation, and as he drives very fast and often makes his journey by way of the smaller by-roads, we decided we couldn't follow him without his becoming aware of it. Practically all we have done, until last week, has been to tap his correspondence and his telephone and depend upon the butler's reports."

"Until last week, you say?" commented Larose. "Well, what have you been doing since then?"

"We've installed a man in the village there, and he's been finding out all he can. He's supposed to be an artist." Mr. Grant nodded. "The whole district between Aldeburgh and Southwold is over-run with people who paint, as I expect you know."

"And what are the two things, then, that you say you have recently found out about Herr Mitter?" asked Larose.

"The first one is this," replied Mr. Grant, "and it proves most conclusively that Mitter is in the habit of assuming another personality at times when he's away from Dunwich. Now listen carefully. Just about a year ago a young officer, a Lieutenant Culley, was on duty in the Tower of London and met with an accident by slipping upon a piece of banana skin. He fell and struck his head with great violence upon the stone pavement and was rendered unconscious. Only for about half a minute, however, and then, beginning to come round, he stared up at the faces of several men who were standing over him. Of course he was very dazed and could not at first realise what had happened, but he declares that the faces he saw during those few moments made an indelible impression upon his memory, so much so that they haunted him for many weeks after and he could never entirely forget them."

"Quite feasible," nodded Larose. "I have noticed myself that in moments of great stress the eye takes an instantaneous photograph of everything, and we can recall it, even after years and years."

"Well, last week, when in the city," went on Mr. Grant, "he encountered one of these men again and he remembered him instantly. He was dressed in rough, common clothes, and looked as if he belonged to some ship. Young Culley had plenty of time to take him in, for he was standing waiting until the traffic was held up to cross the street in Mark Lane. Culley says he would have gone up and spoken to him if the fellow had not looked so gloomy and grim."

Mr. Grant raised his hand in emphasis. "Well, now for the sequel. Upon the night of that same day this young lieutenant was present at the Yacht Club Ball in Harwich and, being introduced to Herr Mitter by a brother officer, he recognised him instantly as the man of both the Tower and Mark Lane, except"—he spoke very slowly—"that the Herr had now shed his beard and was clean-shaven, as he always is!"

"Most interesting!" commented Larose frowning thoughtfully, "and how did you come to hear of it?"

"Lieutenant Culley told his father who was in the Intelligence Department during the Great War, but is an old man and retired now, and the latter rang me up at once. He has always had a suspicion of all foreigners."

A short silence followed and then Mr. Grant continued. "Now you will realise how we are trusting you when I go on to tell you of our second discovery touching the very versatile Herr Mitter. The invisible glass is being manufactured on Foulness Island. You know where that is, of course? Well, up to last week, a week ago today, we had always prided ourselves that no unauthorised persons could by any possibility get on that island. We had taken such infinite precautions that we felt sure we were quite secure."

He shook his head. "But we were quite mistaken, for last Thursday, at about nine o'clock at night, a little motor launch out for a moonlight cruise from Southend, broke down when off the Maplin Light and, a sharp wind springing up, it was driven broadside-on on to the island and broken up. It was carrying twelve excursionists, men women and children, and along with its proprietor and his assistant they had of course, to be given shelter for the night. The whole happening appeared to be quite an accidental one and everyone from the launch inoffensive and exactly what they stated themselves to be. The commanding office of the garrison upon the island questioned them minutely and was of opinion that their answers were all satisfactory. Of the five men passengers, one said he was a city clerk; another that he was a shopman; a third, a tailor; a fourth, the verger of an East End Church; and the fifth, a butcher. So they were all——"

"One moment, please," interrupted Larose. "Was any attempt made to verify their statements?"

"Not at the time," replied Mr. Grant, "for it was impracticable, as only one of them was on the telephone." He went on. "Well the women were taken in charge by the matron and nurses of the island infirmary, and the men were locked up for the night in one of the wards. An aeroplane from Southend, only eight miles distant, was telephoned for to fetch them in the morning."

"Because no civilian aeroplanes are ever allowed to alight upon the island, and it was judged wise to wait for the morning when the Southend plane could pick them up upon the sands."

"But why weren't they sent back in one of the planes upon the island?" asked Larose. "It is common knowledge that there is a big aerodrome there."

"There are special features about every plane used for the island work," replied Mr. Grant, "and we never let the public get too close a view of them." He continued. "Well, the night seemed to pass uneventfully, and by eight o'clock the next morning everyone who had come in the launch was being flown back to Southend, but in less than twenty minutes after they had gone there was consternation upon the island"—he paused dramatically—"for it had been found a sentry had been murdered during the night and his body hidden under a tarpaulin!"

Mr. Grant nodded. "Yes, the sentry was missing at eight o'clock when the sergeant went to change the guard round the compound where the factories are, and tardily noticing some tracks of blood and disturbance in the ground, as if a body had been dragged along, they followed them to where some bags of cement were stacked by one of the outhouses, and protected from the weather by the large sheet of tarpaulin." He shook his head frowningly. "It was a most diabolical murder, and carried out in the most daring way possible, for from all signs the poor fellow had been first stunned, where he stood, with a bar of iron, and then he had been dragged unconscious to where the cement was, and, with his own bayonet, stabbed through the heart. When they found his body it was estimated he had been dead for about four hours."

Mr. Grant shrugged his shoulders. "Of course, everyone was dumbfounded, and for a few minutes no one could hazard even the very slightest conjecture as to who might have been the murderer. Then suddenly someone thought of the excursionists, and a rush was at once made to the infirmary to see if there was any indication that any of the men had left the ward during the night." He made a gesture of resignation. "There was no doubt about anything. The lock had been unscrewed and then replaced, minus some screws; there was a smear of blood upon the floor near the door, and another smear upon a water-bottle upon a shelf near one of the beds."

"No, unfortunately, only smears as if the blood had been nearly dry when they were made. Then with these startling discoveries the Southend police were, of course, rung up instantly, and enjoined to get in touch with the excursionists, all of whom had said they were lodging in the town. They were all found but one, and he had not only not been lodging where he said, but, as was ascertained later, the address he had given in London was also a false one, and he had never been heard of there. He was——"

"No, the tailor, an amiable old man and, according to Colonel Maitland, seemingly the most unlikely of them all to have committed any crime. Another thing, among the finger-prints found in various places in the ward, and upon the cups in which they had been given their morning coffee, the only ones of which no traces could be found were those of this man. It is undoubted that he had wiped his cup after drinking from it."

"But does all this in any way connect up with Mitter?" asked Larose, after a moment's cogitation.

"Yes, in a most startling manner," replied Mr. Grant, "and in one that leaves no doubt in our minds that Mitter is involved in some way, in what happened that night upon Foulness. We are forced to that conclusion by a discovery made, only last Sunday morning, by that man of ours who is now stationed at Dunwich. He saw Mitter start off upon a walk along the cliffs and followed him. Presently Mitter came to the trunk of a fallen tree, lying by the edge of the cliff, and was about to seat himself upon it, when he, apparently, noticed the trunk was damp from a shower of rain of not an hour previously. So he took a newspaper out of his overcoat pocket, and, unfolding it, spread it upon the tree trunk to keep his clothes clean. Then, when after a few minutes he got up and resumed his walk, he left the newspaper behind and our man, out of curiosity, strolled over and inspected it."

Mr. Grant nodded significantly. "That newspaper, sir, was a copy of the 'Southend Chronicle' of the week before last, but not only that, for upon the tide-table on one of the pages, the time when it was going to be low-water round the Maplin Sands, on the very night of the Foulness murder, was scored under with a pencil."

"No," replied Mr. Grant, with a frown, "his butler says he was hard at work upon a painting in his studio upon every day of that week, and never left the house." He went on. "Of course, we do not for one moment believe that the man who declared he was a tailor was Mitter, but we do think Mitter knows of the outrage on Foulness, and that he may have had some hand in the preparations for what was so obviously, an attempt to get hold of a piece of the invisible glass."

Larose looked doubtful. "But isn't that deducing a great deal from very little?" he asked. "And if, as you say, the launch was driven upon the island by a sudden storm, how could it have been a premeditated act? What does the man in charge of the launch say?"

"Ah!" exclaimed Mr. Grant, "that, of course, may raise some doubt"—he shook his head—"but at the same time there are some very suspicious circumstances even there. The man in charge, the skipper, was the owner of the launch, and he states most emphatically that but for the sudden burst of wind the launch would never have gone within miles of the island. On the other hand, the passengers all unanimously declare that he switched off the engine before the storm had started, and one of them, the butcher, a man of intelligence and from all reports of most impeccable character, is strongly of opinion that the engine was functioning quite perfectly until the skipper began to start pulling it about. This butcher, too, has a motor delivery van, and doing all his own repairs, should know something about motor engines."

"And the skipper, of course, denies that he knows anything of the man who gave the false address?" suggested Larose.

"Yes; he swears he had never seen him before," replied Mr. Grant, "but, then again, there is something peculiar there, for when the launch was at the pier head that night and he was shouting for passengers and no one seemed inclined to come, this old man who said afterwards he was a tailor, seemed to act the part of a sort of decoy by himself paying for a young fellow to come, if the latter would promise to give them some more tunes upon a concertina upon which he had already been playing. That undoubtedly induced others to follow, and the launch speedily filled."

"Hum!" remarked Larose thoughtfully. "A lot of little things, but they certainly mount up."

"But there's one thing more," went on Mr. Grant, "and to my thinking it is the most convincing evidence that there was some scheming somewhere." He spoke very slowly. "This man Rook, the skipper of that motor launch, after having been known for many months to be living from hand to mouth, is now in the possession of money, and two days after the wrecking of his boat he paid down no less a sum than £200 towards the purchase of a public house in the little village of Battlebridge, a few miles from Southend.

But Mr. Grant shook his head. "No. We are up against a dead wall there, for the man states he had been saving up the money for years and years, unbeknown even to his wife, and we cannot prove to the contrary. It appears he is a bold, determined fellow with a bulldog courage, and he is quite aware that if he sticks to his story he is perfectly safe. He was a policeman once, and is afraid of no one."

"And was there nothing suspicious about any of the other excursionists?" asked Larose.

"Nothing at all! They are all what they purported to be—quite respectable people in humble walks of life, and they all gave their correct addresses and occupations."

"No, it was judged best that the sentry's death should not be broadcast, and so they were just told that one of them had broken out of the ward during the night and stolen from one of the officers."

"And you don't think this man succeeded in getting into any of the factories or the place where this glass is made?"

"No. Happily we can be quite certain there for all the fastenings were intact and none of the inside watchmen had anything to report."

A long silence followed, and then Larose suddenly threw back his head and began to laugh. "And I was only thinking today that adventure would never be coming my way any more, but here it is at my very door." He sobered down instantly, and his eyes glinted. "Yes. I'll take it on," he said. "I'll help you in any way I can!"

"No, no," interrupted Larose sharply, "that's not the way to set about it. We must pick up the trail from where it started, and not try and work backwards from Mitter himself." He rubbed his hands together delightedly. "Yes, I'll come up to town with you to-morrow and be flown over to Foulness Island"—he hesitated a moment—"after I've had a little talk with Lieutenant Culley and spent an hour or so in the City. I've a great idea that we'll find out something very quickly."

And find out something, very quickly, Larose did, for the next evening a few minutes before six o'clock, and just when Mr. Grant was about to leave Whitehall for his home, he was being ushered into room thirteen, all prepared to furnish a very important piece of information.

"Yes," he began briskly and with no preamble, "you are quite right in one thing about Herr Mitter. He is probably a very dangerous man, and most likely to be a deadly enemy of Great Britain. His real name is Mangans, and his father was Leopold Mangans, the spy who was shot in the Tower on September 28th, 1914. I have seen a photograph of Mangans, and Mitter is his living image. Mitter probably visits the Tower upon every anniversary of his father's death. Lieutenant Culley met with his accident on September 28th last year, and it was upon September 28th last week that he encountered Mitter in Mark lane. Mitter had evidently just been making his annual pilgrimage to the Tower, and no wonder the lieutenant thought him looking sullen and grim."

"But how in heaven's name did you guess——" began Mr. Grant with eyes wide in his astonishment.

"I didn't guess at all," interrupted Larose sharply. "I associated Mark Lane with the Tower directly you mentioned the street, for the two places are so near to one another, and then questioning Lieutenant Culley, the coincidence of the two dates struck me instantly. After that a few enquiries at the Tower settled the matter beyond doubt."

Mr. Grant bowed. "You are a great artist, Mr. Larose," he said quietly, "and already we are much beholden to you."

CHAPTER VI
THE CONSPIRATORS

THE chimes of the beautiful old clock in the lounge of Dunwich Hall had just tinkled the hour of eleven upon the night of the same day that Larose had made his startling announcement to Mr. Grant, when Margaret Advent, Herr Mitter's parlormaid, scraped lightly upon her master's studio door and a low voice bade her enter.

Margaret was certainly a very pretty girl and no one would have said she came of common stock. Built rather on the tall side, she had a supple and beautifully proportioned figure. Her profile was clean-cut and aristocratic, she had large grey eyes, a very pretty mouth, and a faultless complexion. Her hands were small and dainty.

She had no knowledge who her parents were, for one night, the night of Advent Sunday, nearly two and twenty years ago, she had been found upon the doorstep of the Foundling Hospital.

"A love child, of course!" had nodded the grizzled old doctor, when he had first examined the pink and white bundle that had been lifted from the basket. "What despicable people there are in this world! Someone has taken the best that life can offer and yet been willing to make no sacrifice in return!" He shook his head. "But how I'd like to punish them!"

And so Margaret had grown up in the usual way of those whose parents have given all to passion and nothing to its consequences—Foundling Hospital. Babies' Homes, a cold and money-stinted orphanage, and then out into domestic service.

Her first place had been in a country vicarage, with a childless old clergyman and his wife. She had been very fortunate there, and treated with great kindness, among many privileges and had been allowed the unrestricted use of an excellent library. Then her master, noting the bent of her inclinations, had mapped out a course of studies. He had given her lessons in French and German and been delighted with the proficiency she had so quickly acquired. "One day, my dear," he once said smilingly, "you should have a much better position than that of a domestic servant. You have brains and intelligence and if you pick your steps carefully, who knows what your future may not be. Any man should be proud to have you for his wife."

The old clergyman dying, she had next obtained a situation with a titled woman of considerable means, and had there been trained most efficiently in the higher walks of her calling.

With her attractive appearance she had, naturally, had plenty of admirers, both among her fellow servants, and the many visitors who had come to stay with her titled mistress, but with a strength of character she could hardly have inherited from her mother, she had shrouded herself in cold reserve and firmly checked all advances. She had set a value upon herself and was not going to give herself to anyone lightly.

Tiring at length of her surroundings there and desirous of a quieter life, she had answered an advertisement in the 'Morning Post' and so had come to Dunwich Hall, quite heart-whole and mistress of her affections.

She had liked the place from the very first, and her master, too, for recognising at once that she was no ordinary servant, he had soon put her on a different footing to the others and entrusted her with many little matters that, up to then, he had always done for himself. He let her tidy his desk, file any letters that he wanted keeping, and gave her charge of the household accounts. Later, too, he encouraged her to practice upon his typewriter and in time she attended to any unimportant correspondence for him.

So gradually, but with Mitter always treating her with great respect, an intimacy sprang up between them. Subordinating all his passions to the one of avenging his father and serving his country, Mitter had all his life allowed himself no weakness for the other sex, and for a long time his liking for Margaret—she had told him the story of her life—was mainly of pity and entirely devoid of self-interest. But it was unnatural he could go on for ever uninfluenced by her beauty, and one day as he was bending over her when she was writing, and their heads came close together, upon the impulse of the moment—he kissed her.

"But I'm a servant, Herr Mitter!" she gasped indignantly and with heightened color. "You forget that!"

He was angry with himself for what he had done, but did not allow her to perceive any sign of it.

"There is no need for forgetting that," he smiled, "because I never remember you as one. You are as perfect a little lady as any of the society girls who come here, and it is only by an unhappy chance that you are not in your right position now. Perhaps, one day your parents will claim you, and, then all will come right." He patted her shoulder gently. "Now, you forget that I have kissed you, and then no harm will have been done."

But she did not forget it. His caress had awakened in her the knowledge, that if she did not actually love him, she was nevertheless very fond of him, and the woman-nature in her thrilled at the realisation. So it was not very long before Mitter saw from her manner towards him that his attentions would not be unwelcome, and he smiled to himself at the hold, he could so plainly see, that he had obtained upon her.

But he was by no means a passionate man, and never attempted to pursue the adventure any further, being quite content to bind the girl to him by a liking that, he knew, would be all the stronger, because it was permitted of no outward manifestation. As we have said, he was not minded to entangle himself in any intrigue that might tend to weaken the great single purpose of his life.

Then suddenly an occasion arose that made Mitter realise what a great help Margaret might become to him. One of his agents had found out that reports were reaching the authorities, of such a nature that they could only be coming from someone inside Dunwich Hall, and Mitter knew at once that the informer must be his butler.

So he appeared to take the girl into his confidence and disclosed to her, in much the same way that the very plausible Mr. Worley had explained to the innocent Tom Skelton, that he was a political agent, and residing in England for the purpose of obtaining all information he could that would be of service to his country.

No such word as spying was used, and he gave Margaret the impression that his work was just the ordinary routine of international life, as carried out among one another by all the European Powers, and if his activities were of an unlawful nature, then it was only a case of tit for tat, for of course Great Britain's had her agents, too, all over the world.

"It's just a battle of wits, my dear," he smiled, "and if any of us get caught"—he shrugged his shoulders—"then we are punished as political offenders." He nodded. "We go to prison."

Then he told her that he believed the butler was being bribed to find out all about him and suggested that with her greater opportunities, whenever she could, she should get hold of Dempster's letters and bring them to him, or failing that, make copies of them for him to read.

Margaret did not at all like the idea, but the first of the butler's letters being obtained and steamed open, and she saw it was as her master had thought, then her indignation at Dempster's treachery overcame all her scruples, and from then on she was willing to do anything Mitter wanted.

She nodded. "The house is very dull without you," she replied. "Dempster has written two letters, but I could only get at one of them to open." She smiled. "He wrote you had been very moody lately and hardly spoken to anyone."

"Oh! he did, did he?" laughed Mitter softly. "That'll be exciting news for them up at headquarters. Many people called?" he asked.

"Just a few, but Dempster said you were very busy painting, and he did not like to disturb you." She drew out a paper from the bosom of her dress. "I've got a list of them here," and then when Mitter was scanning down the paper she went on. "I opened the door to some when Dempster was off duty, and among them was Lieutenant Fortescue." She smiled. "He would come in, for he said he had an important message for you, and if he couldn't see you, must send it to you in writing. I got him some paper and an envelope and he wrote it in the morning room. I put it on your desk."

"Yes, yes," nodded Mitter, "I've read it, and it was only an excuse. He suggests a round of golf with me when I've got the time to spare." He frowned. "Of course, he only came in to have a talk with you. I've noticed his eyes follow you about much too much, whenever he comes here."

"He asked me to go with him to some pictures somewhere on Saturday," continued Margaret, looking very demure. "He says he'll meet me outside the village in his car, if I write and tell him I can come."

Mitter's frown deepened, and for a few moments he paced restlessly up and down before the fire. Then he said reluctantly. "And you'll go, Margaret. It is my wish."

"What! Go out alone with him!" exclaimed the girl, very surprised. "You mean it."

Mitter pushed her gently down into an armchair and balanced himself up on the side. He stroked her hair softly. "Look here, dear," he said. "I want you to cultivate that young man. I've just found out that his cousin is Flight-Commander Fortescue, who is stationed in a Government reserve in Carnarvonshire, where those wonderful invisible aeroplanes are being assembled. He's one of the chief instructors there." He looked intently at her. "Now you might get some information out of that young man that should prove most valuable to me."

"Oh! but I wouldn't get Lieutenant Fortescue into any trouble for anything!" exclaimed Margaret instantly. "He's a nice boy, and I rather like him."

"Of course you do," returned Mitter quickly, "for besides being very good looking, he's a gentleman and well bred. There's only that cousin and a very old uncle to stand between him and a baronetcy." He went on smilingly. "No, no, you won't get him into trouble, and if you find out anything from him, it will never be known from whom it has come. You can just draw him out tactfully and he won't realise he's told you anything. You understand?"

For a long moment Margaret did not answer, and then she turned the conversation and asked slowly. "Are you going to live here always, Herr Mitter?"

He hesitated. "No-o, not always," he replied. "I shall go when my work is done."

She looked up at him and spoke very firmly. "And will you take me with you then." She nodded. "I should like to go."

Mitter frowned. "I can't promise you, Margaret," he replied, "for the future is always very uncertain for me." He looked at her curiously. "But why are you asking me that now?"

"Because"—she hesitated—"because the other day that Fortescue boy started me thinking about a great many things, and I realised I was living a very aimless life that seems to be going to end nowhere." She laughed lightly. "You see, I am getting old, Herr Mitter, and I don't want to be always a servant. I want to marry and have a home of my own one day, and when I was talking to Mr. Fortescue I thought"—she blushed prettily—"I thought I could very easily fall in love with him if I got the opportunity." She drew herself up. "I know he likes me."

"But do you think he would marry you, Margaret?" asked Mitter with a rather amused smile.

"Well, he certainly wouldn't get me in any other way," she replied sharply. She thought for a moment. "Yes, I think he would. An instinct tells me so." She nodded proudly. "I shouldn't be a disgrace to him, anyhow, for as you've often told me, it's only by misfortune that I'm a servant."

A long silence followed and then Mitter heaved a big sigh. "You are quite right, my child," he said. "Make the most of your prettiness and do the best you can for yourself. Go out with Mr. Fortescue and have a good time." He spoke briskly. "Now, I tell you exactly what I want you to get hold of for me. You're a clever girl, and if you go tactfully about it, I'm sure this boy will tell you anything you ask."

Herr Mitter had another visitor that night, long after Margaret had left him, and he sat brooding before the fire. He heard a muffled knock upon one of the outside walls, and he rose hurriedly to his feet and shot to the bolt of the study door. Then he went quickly to the big cupboard at the far end of the studio, and unlocking it, with a key that he selected from a bunch he took from his pocket, he swung to one side some painters' coats that were hanging from ringed hooks along a rail. Then he pulled forward a wide hinged board at the back of the cupboard and disclosed an age-old oak door. The handle of the door turned, there was a current of cold air, and a man stepped into the room. The two doors were immediately closed.

"Hullo, Carl," he exclaimed cheerily. "I heard you come back. Any news of that doctor on Foulness?"

Mitter nodded. "The best, Bernhard," he replied. His face was all smiles. "I found who he was without the slightest difficulty. He's a Dr. Benjamin Howard Fergus, Professor of Physics at Cambridge University. His home is in Cambridge, but he was taken away from his university duties last February."

"Splendid!" exclaimed the other enthusiastically. "But tell me, how did you get on his track?"

Mitter laughed. "Remember, I knew from our Manor Park friend that one of his Christian names was Benjamin, and that his wife had recently had a baby. So feeling sure that as a doctor of science he was considering himself an important person I guessed a notice of the birth would be in the London papers. And there I found it in 'The Times'—'On September 2nd. to the wife of Dr. Benjamin Howard Fergus, of Trumpinton road, Cambridge—a son.'"

Bernhard rubbed his hands together delightedly. "So, how very often," he exclaimed, "do our little petty vanities give us away! Go on."

"So I went down to Cambridge," continued Mitter, "and stayed there for four days to make sure of everything." He laughed again. "I was fortunate all along, for going to see where he lived, I saw an old clergyman coming out of the house next door. I followed this clergyman to a church where he was about to officiate, and sat through the service. Then I enquired about him of the verger and learnt that he was the rector of the church. So I said I wanted to speak to him, and being taken into the vestry, asked permission to photograph a very beautiful reredos they've got there. The old chap was delighted, and took me round to examine the other things in his church Then I made a donation of £5, and he at once invited me to his home for lunch."

"And you pumped him about his neighbor, of course?" suggested Bernhard gleefully.

"Yes, over an excellent little lunch with some really good burgundy. I admired the chrysanthemums next door, and he told me they were the pride of this Dr. Fergus, whom he said was a very distinguished man. Then he went on to tell me all about him; how the doctor, although still only in the early thirties, had already made a name for himself in the scientific world, how it was common knowledge he and his bosom friend, Professor Carling, the professor of chemistry at the university, used to spend nights and nights together in their joint laboratory, and, finally, how Dr. Fergus had temporarily vacated his chair at the university to take up research work, or what nature no one knew, in London."

"Two of them, eh?" ejaculated Bernhard. "Then this Professor Carling must be in the know, too."

"There's no doubt about it," nodded Mitter, "for the two are quite inseparable."

"Then we needn't wait for this Dr. Fergus to come on leave again," said Bernhard excitedly. "We can get hold of this friend at once, and wring the secret from him."

"No, no," said Mitter quickly, "we must get them both together." He lowered his voice and went on impressively. "Don't you see, if we get hold of Dr. Fergus"—he hesitated and made a grimace—"and put pressure on him to tell us of what the glass is made, how do we know he'll be giving us the right formula? He may deceive us and we shan't be certain we've got the real thing. But"—his face was very grim—"if we kidnap them both, keep them apart from each other and get the secret from each of them in turn, we shall be sure they are telling the truth if the two formulas coincide." He shook his head. "How otherwise shall we know we are not being cheated?"

"Hum!" remarked Bernhard thoughtfully, "you're right, but it doubles our difficulties."

"No, not quite," returned Mitter quickly, "for being such inseparable friends, we shall in all probability be able to lay hands upon them both together."

"I've thought it all over most carefully, and have been making a lot of enquiries," replied Mitter. "I've found out golf is their only hobby, and, with any luck, we ought to be able to get them on the golf course itself. Their custom is to golf very early, starting about half-past eight, and they caddy for themselves, probably because their conversation is so private. Well, I've reconnoitred that golf course most thoroughly, and the seventh green lies in a hollow and out of sight from everywhere. Also, which is a very fortunate circumstance, it's only about a couple of hundred yards from the Newmarket road. So we could seize them there, and, our luck holding, we could bundle them in a car and get away without a soul knowing what had happened."

"That also I am in the way of providing for," replied Mitter, "for I've marked down a house on Scoulton Mere, about sixteen miles from Norwich and six from Wotton. It's been vacant for about a year, is situated in an isolated position, and is right on the bank of the mere"—he nodded significantly—"a lonely stretch of water that would keep its secrets well."

"Not you," replied Mitter promptly. "You'll have to keep out of it. I shall carry it out myself, for I know the ground. I shall only need two helpers, for neither the doctor or the professor are muscular men. Fergus is tall and slight, I've seen his photograph, and Carling is a small man. About the house, I shall get Wenham to arrange that. He looks impressive and prosperous, and we'll pay a year's rent in advance, so that no references will be needed."

"If they are reasonable they'll come to no harm, and be allowed to go after a time. If they are stubborn"—he shrugged his shoulders—"well, we'll have to deal with them in a way they won't like." He frowned and shook his head. "It may be an unpleasant business, but we can't afford to be squeamish in a matter like this, and we'll have to get the formula out of them in some way. If the worse comes to the worst, they'll never be heard of again."

"But one thing," said Bernhard, "if you eventually let them go, they mustn't be able to furnish any description of you afterwards." He looked uneasy. "This affair will cause a hell of a sensation, and, remember, you are under suspicion as it is."

Mitter laughed scornfully. "The description they'll furnish won't be worth a tinker's damn. My get up, which in Cambridge was perfect, and when I have my little talk with them I'll be looking a different man again." He went on. "Oh, and another thing. The third day that Rector took me to the County Club for a hand of bridge, and I learnt quite accidentally that that young Fortescue who calls here so often has a cousin, an air-commander in Carnarvon." He looked intently at his companion. "I'm putting Margaret on to him. He's asked her to go to the pictures on Saturday and she's going."

Bernhard opened his eyes very wide and spoke hesitatingly. "Is that safe?" he began, and then he went on quickly. "But, of course, we can trust her. She's a girl of firm character."

Bernhard laughed. "Yes, it's funny; she'd go through fire and water for you, who at heart have no liking for a pretty face, and yet for me, who can appreciate one"—he made an expressive gesture of disappointment—"she'd do nothing."

"No, and I'm not likely to, either. I'd only get a snub for my pains. She'd not be easy for anyone to get over."

Mitter changed the conversation. "By the bye, yesterday, making a break in my search for a suitable home, I took a day's shooting at Carmel Abbey and there was introduced"—he smiled sardonically—"to three important officials of the British Secret Service. They were Sir Robert Carnaby, Colonel Bevan, and the inscrutable-looking Mr. Grant, head of the counter-espionage here. They knew who I was, right enough, but didn't dream I knew what their official positions were and it was vastly amusing to watch them taking me in." He frowned. "But I rather regret I went there now, for I happened to be in splendid form with my shooting, and I'm inclined to imagine I made them think a bit. Another thing, too, I didn't like. The three of them were going to stop the night at Carmel Abbey and I don't want"—his frown deepened—"I don't want Larose to be brought into our affairs."

"He's not likely to be," scoffed Bernhard, "and if he were, he'd not find out anything where the shrewdest brains of the B.S.S. have failed."

"Oh, I don't know so much about that," disagreed Mitter, promptly "He's not an ordinary man, by a long chalk, this Larose. He's a dreamer, if you like. He's bursting with imagination, and yet he's eminently practical when anything has got to be done." He shook his head vigorously. "Yes, by Gad, if it came to a scrap with us, he'd ask no quarter and would give us no points in ruthlessness. He'd stick at nothing." He looked at his watch. "But come on now, Bernhard, you must have a lot to tell me."

CHAPTER VII
A DUEL OF WITS

AT ten o'clock in the morning, just a week after the events recorded in the last chapter, John Ebenezer Rook, proprietor of the Cow Inn in the pretty little village of Battlebridge, was regarding with great satisfaction the newly-painted sign over the inn door. The sign depicted a very red cow, with long horns, and a very fierce expression. The artist who had painted it had received ten shillings and two pots of beer for his labor and that he had done his work well was the opinion of both the landlord and his decidedly pretty-looking wife who was standing beside him.

"That'll make them all sit up," nodded Rook decisively, "although I wish he'd make her look as if she was going to give a bit more milk." He nodded again. "Yes, we're going to make things hum here, and what with a couple of good sows and plenty of fowls, I'll soon be a blooming farmer as well as a publican."

"You're very wonderful, John," said his wife, looking up at him admiringly, "and I still can't think how you've managed it. It's perfectly lovely being here after living in that horrid little back street in Southend!" Her eyes turned to the little river and the green fields so near and she added with a sigh of great happiness, "The babies will grow up strong and healthy too."

"Of course they will, Jinny," agreed her husband with a chuckle, "and you'll be a different girl now as well. With good country air and plenty of home-grown stuff to eat, you'll be so plump and rosey that when your mum comes to stay with us, she probably won't know you." He patted one of his trouser pockets, and healthy metallic sounds ensued. "Twenty-eight and thrippence in the bar last night and what it'll be on Saturday I don't know!" He took out a cheap watch, very shiney and very new. "Oh! but I must be off now and collect those sows." He nodded to his wife and turned away. "Mind, I shan't be long, not more than half an hour, and if that insurance chap comes, just make him wait. Give him a half pint and keep him talking until I come," and off he strode jauntily up the road.

Not ten minutes later, a smart two-seater car drew up before the inn door, and a pleasant-looking youngish man jumped out and made his way into the bar. There was no one about, and he had to tap loudly upon the counter before Mrs. Rook appeared.

"I'm sorry to have kept you waiting. I was——" she began, and then noticing the well-dressed appearance of the caller, she broke off suddenly and asked—"Oh! you come about Mary Belle insurance, do you?"

Larose, for it was he, half nodded and evaded the question. "But isn't Mr. Rook in?" he asked, with what the girl thought was such a nice, winning smile.

"No-o," she replied, "but he'll only be gone a little while. He went to bring home some pigs we've just bought. Do please sit down and have something to drink."

Larose at once complied, as it he were quite pleased with her hospitality and then no customers arriving, he sat and talked for about twenty minutes, until Scampy himself appeared.

"The gentleman from the insurance company," explained Mrs. Rook, and Larose noticed Scampy's eyebrows came down and he gave him a hard look.

"Good morning! Mr. Rook," returned Larose politely. "Can I have a word with you?" and Scampy, with a curt nod, led the way into a small parlor, just off the bar. He pointed to a chair, and then very carefully closed the door behind them.

"So, you represent the insurance company then?" he remarked, taking a chair himself, so that there was now the breadth of a small table between them.

"No," replied Larose, still speaking in most polite tones. "Your wife suggested it and I didn't undeceive her. I've nothing to do with the insurance people, and also"—his voice hardened just a little—"you'll be pleased to learn I don't come from the police."

Scampy sat up with a jerk, frowned, and then shook his head contemptuously. "That wouldn't worry me," he said sharply. "I've told them all I know and have done with them." He shook his head again. "I've nothing on my conscience."

Larose smiled grimly. "I'm not quite so sure about that, Mr. Rook," he nodded, "or, rather, to put it plainly, I'm quite sure to the contrary."

But Scampy appeared quite at his ease and took out a cigarette. "Well anyhow, who are you?" he asked after he had struck a match. "Another blanky newspaper man, I suppose?"

"No, I've nothing to do with any newspaper," replied Larose. He looked round to make sure the door was closed and added quietly—"I come from the British Secret Service."

Scampy took the cigarette out of his mouth and with widely-opened eyes made no attempt to hide his surprise.

"From the Secret Service!" he exclaimed. He blinked like an owl several tunes and then looked contemptuously again. "Well, how the devil does that concern me?"

"It concerns you so much," said Larose softly, "that if you don't give me satisfactory replies to my questions"—he looked very stern—"then it's good-bye for you to this pretty little inn, those two sows you've just bought and all your prize fowls." He nodded. "It means a stretch for you, my friend."

Scampy's wind-tanned face paled ever so little, but he put on a bold front. "See here, Mister," he said scowlingly, "you'll not frighten me, for I tell you straightaway that I'm as tough as hell." He laughed scornfully. "Why, damn it all, I was in the police once and know you want evidence to down a man."

"I was once in the police, too," smiled Larose very confidently, "and I've got that evidence right enough. I was a C.I.D. man three years ago, and my name is Gilbert Larose."

Scampy's eyebrows came together with a click. "Oh, that Larose chap, are you?" he growled. He looked just a trifle uneasy. "I've heard of you, of course. Pretty smart, but a bit too ready with your gun!" He spoke up angrily. "Well, tell me straight what your idea is of what you've got against me. Put your cards down, Boss, and don't beat about the bush."

"Good!" exclaimed Larose, "then we'll get to business at once." He leant across the table until his face was as close to Scampy's as it could get. "I've been six days, Mr. Rook," he said, "finding out all I could about you and I assure you I've found out quite a lot. To begin with, you've been lying heavily to the police. No, no, don't get into a rage and don't shout, or you'll upset that nice little missus of yours." He nodded. "If I find you reasonable it is quite possible she need know nothing of what you've done. Now listen." He lowered his voice to the merest whisper. "Do you know, my friend, what happened that night when you were on the island?"

"Yes," grunted Scampy, "one of the passengers from my launch broke out of the room where we had been locked and stole from the officers' quarters."

"No," replied Larose quietly, "he didn't steal. He murdered! He killed a sentry!"

"He wasn't old," snapped Larose, "and none should know that better than you. He'd only taken out his false teeth and made himself up." He shook his finger menacingly in Scampy's face. "That fellow bribed you, Rook, and you and he were working together, when that night you deliberately wrecked the Mary Belle."

The color surged back instantly into Scampy's face. "That's a lie," he snarled. "They are both lies. I didn't wreck the Mary Belle and I'd never clapped eyes on the old man, until he leant over the pier head that evening and called down he was coming for the cruise."

"You had never clapped eyes on him!" jeered Larose. "Why, you forget, Rook, that you told everyone what a wonderful catch you'd got in that Mr. Danker, a rich gentleman from the Royal Hotel who was paying you £4 a day for the hire of your launch and was bringing fine lunches of sandwiches, pork pies and rum and beer!" He laughed scoffingly. "Never clapped eyes on him, indeed! Why for three days, from 10 to 5, he was sitting within 6 ft. of you all the time." He dropped his voice to quiet tones again. "You are lying to me, sir, and you know it."

"But he wasn't the old man!" he said hoarsely. "They were quite different persons. The man who hired my launch was big and stout and with a very dark skin."

"And wore glasses," went on Larose jeeringly, "so that people could not see his eyes, and a wig of long hair!" He snapped his fingers together. "You big ninny, if you are as innocent as you make out, can't you realise his skin was dyed and he was all muffled in clothes and that big ulster to make himself look stout. Oh! yes, I've got his description from a dozen people in the pier. You talked so much about him and your luck, that everyone was interested and took note of him."

Scampy made no comment. He was like a man in a dream, and his thoughts were all confused.

Larose went on. "And for two of the days he hired your launch, you took him bang opposite Foulness Island and anchored just off the South-East Maplin Buoy." He looked incredulous. "Do you mean to tell me you weren't spying out the shore and making all preparations for that night?"

"Spying out the shore!" exclaimed Scampy, now waking up and jeering in his turn. "Why, I lived for years in Southend and know every yard of that shore. I've gathered cockles for bait there, a hundred times!"

"And you still declare," went on Larose, "you had no knowledge the tailor-man was that Mr. Danker?"

"Then if I acquit you of being, knowingly, a co-murderer with him that night"—Larose spoke very sternly—"you have still to answer the charge that you were bribed by one or other of them." He snapped his fingers again. "Someone gave you money last week and there isn't the slightest doubt what for."

"A moonlight cruise of two hours for nine pence," laughed Larose. "Nine shillings for your 12 passengers, and out of that you had to pay for your oil and petrol, and give your assistant four bob. You made a lot of profit, didn't you?" He sniffed contemptuously. "Great Scot! Captain Rook, what jury would believe that?"

Scampy steadied his features to the most wooden expression he could assume and made no reply. He did not feel quite so confident again.

Larose laughed a second time "Yes, and I've had a little talk with that chap who sold you this pub. You've certainly primed him well what to say, but he'll break down right enough in the witness box, and we'll get out of him that you saw no earthly chance of raising any money when you called here a fortnight ago."

"I didn't want to break into my savings," said Scampy suddenly. "I keep my private affairs to myself."

"Good judgment," agreed Larose drily, "for they want keeping dark." He appeared to remember something. "Oh! and another thing, my fine fellow, I've been over on to the island and had a good look at that engine of the Mary Belle." He seemed very amused. "You made a nice mess of that magneto, didn't you?" His voice rose a little. "Filing the platinum point until there was no platinum left! You, an experienced motor mechanic, who's worked on the racing cars at Brooklands, using a big, coarse file!" He whistled. "What'll the insurance people say when I tell them that? Suppose I wait here for that agent of their's, whom your wife said is coming here this morning!" He shook his head doubtfully. "A lot of chance then you'd have of touching any of that £75, wouldn't you?" He nodded. "Yes, I could make myself very disagreeable."

Scampy wiped the perspiration from his forehead with the sleeve of his coat and looked out of the window. The sun was shining and he could see the bright green fields outside. He could hear his wife singing their little baby to sleep. The pleasant smell of beer and of the sawdust upon the floor of the little bar came up into his nostrils. It was a little Paradise they had come into, and now it seemed they were going to be turned out. Verily he was in the toils! A dreadful fear gripped him, and with all his courage, he had the look of a stricken animal, as he once more faced Larose.

Larose suppressed the elation that he felt, for although the expression upon Scampy's face was dark and menacing, he sensed undoubtedly that he had at least in part, broken down the man's resistance.

He smiled. "To strike a bargain," he replied, "to hold my tongue and leave you in peace, provided you give me certain information that I want." He spoke quite friendly. "First, let's have another glass of that good ale of yours, and you have one with me this time"—he smiled—"or a tot of rum, if you'd prefer it, a good tot, like that Mr. Danker gave you."

Scampy made no comment, but, leaving the parlor, returned in a few moments with two pewter pots, and placing one before Larose, resumed his seat. The expression upon his face was inscrutable.

Larose took a deep draught and then remarked casually: "By the bye, talking about rum—did you sleep well that night when you were upon the island?"

"Never woke up once," frowned Scampy, and in no wise replying in the friendly tone of his interrogator.

"Of course you didn't," commented Larose, "for that rum old toothless gave you all was doped. We found traces of veronal in the few drops left in the flask, which, fortunately, had not been thrown away. You all slept like dead men, and that young chap with the concertina actually drowsed off again as he was being flown back to Southend in the morning." He nodded. "I've had a talk with everyone of them."

"Well, what do you want?" asked Scampy sullenly. "Get down to business as you said before."

"Well, the exact position is this, Mr. Rook," began Larose. "As I told you I'm acting for the Secret Service, and I'm not interested two hoots in what the police or the insurance people are doing. They can look after themselves." He eyed Scampy intently. "All I want is to get upon the trail of that Danker man, and if you make a clean breast of everything to me, not only will I not pass on a single word of anything to anybody, but also"—he took out his pocket-book—"I'll make you a present of £50 down on the spot, cash down, at once."

Scampy's jaw dropped in amazement, his eyes opened very wide, and he glared hard at Larose. He didn't speak for quite half a minute.

"And—if—I—tell—you," he said slowly, his voice strengthened, and there was the ghost of a grin upon his face, "if I make up a yarn, how do I know you won't blab? Where's my guarantee that you are on the square with me?"

Larose made a scornful gesture. "Where are my witnesses?" he asked. "What evidence could I adduce? You could deny everything! You've been in the police and must know exactly what the position is."

Scampy nodded towards the little wad of notes that Larose had laid upon the table. "Whose money is that?" he asked curtly.

"It's the Government's, you mean," said Scampy. "You'll have to account for it to someone. You'll have to tell that you gave it to me, and then there'll be another one in the know."

"Certainly not," replied Larose. "I tell you I'm all on my own." He shook his head. "I'm a well-to-do man, and I'm doing this for the sport. I want to succeed where others have failed. Great Scott!" he went on impressively, "do you think any department in the Government would send me down to compound a felony, for that's what I'm offering to do." He looked contemptuous. "Here are you—a man who deliberately threw away his boat and callously exposed twelve persons to the danger of losing their lives, a man who accepted a bribe to betray his country, a——"

"No, no, Mister," broke in Scampy sharply. "I didn't do either. Go a bit easier, please. I was bluffed, if you must have it. I was sucked in"—an angry light blazed up into his eyes—"and that's what makes me half inclined"—he hesitated, and then grinned again—"to spin you that yarn." He nodded grimly. "No man's going to take down J. E. Rook and get away with it. So there."

But Scampy hesitated. He moistened his lips, he frowned and he swallowed many times.

"Come on," urged Larose gently. "I'm your friend or your enemy, and remember"—he held up a finger warningly—"that insurance man may be along any moment now." He pointed to the notes upon the table. "And in addition to those, if I lay the man by the heels, I promise you I'll put down another fifty."

Scampy hesitated no longer. "All right," he said, "I'll tell you everything. I'll have to trust you, but I see you're a chap something like myself. Maybe you're not too particular sometimes, but you'll keep your word when you've sworn anything." He looked uncomfortable. "Not that that Danker man wasn't pretty good in his way. I got the second half of what he promised me, by the post next day. Still"—he swore a deep oath—"I'm no traitor whatever I am. I lost three brothers in the Great War and I don't forget it. So here goes."

And then he proceeded to tell Larose everything, and as he warmed up, he told his story in a sheepish but unhaltering way, that convinced his hearer he was speaking the absolute truth.

He told of his approach by Mr. Danker, of the long conversations they had had, of the bet that was supposed to have been made, of the money he had been paid and all that happened afterwards.

"So, I didn't pile up my boat," he said. "It was just by chance that that darned wind sprang up when it did. I just meant that the Mary Belle should drift on to the sand and there would have been no danger for any one. As it was, I admit, I was scared stiff, and we were devilish lucky to escape as we did."

When his tale was over, the delighted Larose proceeded to question him briskly, and drew out of him many personal little details about this Mr. Danker that Scampy had not thought worth mentioning; how the former had always brought a bottle of milk for himself, how he had munched chocolate like a school girl, and was never without a thick blue-paper covered slab in his pocket; how he smoked strong cigars, much too strong for Scampy who had been given one, how he made little jokes and laughed over them himself—"Ah!" exclaimed Scampy, sharply here, "now I remember something that makes me think you are darned right. Both Danker and that old toothless man bent their heads forward in the same way when they were mused. Yes, yes, I'm sure of it." He nodded violently. "Gosh! what a baby I've been!"

"It was that rum that made me first think they were the same man," smiled Larose. "That Danker chap, with his dark glasses, his rug, his cushion, and his luncheon basket was a bit of a conspicuous figure, and I soon traced him to where he used to buy the beer. Three days in succession he bought two bottles and a gill of rum at the Kings Hotel, and then, the last evening, after he had come off the pier, he called in and bought a pint flask of the spirit, evidently to take it home and doctor it up, in case any occasion should crop up when he wanted to put anyone to sleep. I also found out——"

"Oh! Oh!" interrupted Scampy excitedly. "I remember something now that will please you. I've got a cloak-room ticket that he dropped the last day he came in my launch. I'd forgotten all about it. I found it after he had gone." He began fumbling in his pockets, and then after a few moments, he stopped and his face took on a very worried expression.

"Oh! don't say you lost it!" almost wailed Larose. "It will probably be worth that extra £50 to you!"

Suddenly Scampy looked relieved. "I know where it is," he said. "It'll be in my navy coat pocket," and in less than a minute Larose was in possession of the precious paper.

"Excellent!" he nodded delightedly. "This may be a great help to me. My conscience, but if I catch this J. Reynolds calling for his bag!"

The door opened and Mrs. Rook appeared. She looked rather bewildered. "John," she said haltingly, "there's another gentleman here, and he says he comes from the insurance company, too!" Her eyes fell upon the notes on the table and she opened her mouth very wide.

"Oh! that's all right!" exclaimed Scampy heartily. "He's the right man." He nodded towards Larose and looked very pleased. "This gentleman comes from a London newspaper, and they are giving me £50 for my story of the wreck. I've just been telling him all about it," and he picked up the notes, and folding them methodically, put them in his pocket.

"Here, I say," said Larose with a frown, directly Mrs. Rook had left the room, "you were pretty ready with your explanation then, weren't you? You must have a jolly good imagination!" He looked troubled. "I hope to goodness that all you have been telling me is the truth!"

"Quite, governor," laughed Scampy, "I've added nothing and left out nothing that I can remember." He bent over the table. "My wife's the best of girls and the apple of my eye, but it never does to tell a woman too much, for they're weak creatures." He looked very knowing. "If she hadn't been a bit that way, Jinny would never have married a rough, coarse chap like me." He nodded. "She thinks I'm Christmas!"

"Well, one thing more," smiled Larose, apparently quite reassured. He took a well-folded sheet of the 'Sphere' out of his breast pocket and laid it flat upon the table. "Now tell me if any of those men there look like Danker or that toothless man."

"Greyhounds!" remarked Scampy as he bent over it. "A coursing meeting, eh!" He studied the photograph carefully and then shook his head. "Sorry, Boss," he said, "but I don't think so. You see, if that Danker man was in a disguise, as you say, then I'd never be able to recognise him again. As for old toothless—why old toothless looked sixty and much older than anyone there."

And that was the only disappointing part of the morning to Larose, for among the men in the photograph was Carl Mitter, of Dunwich Hall.

CHAPTER VIII
HOT UPON THE TRAIL

THAT same night Larose was sitting in an upper room of a small house in Pimlico. The house belonged to a policeman whom he had known in his detective days, and he was making it his headquarters whilst pursuing his enquiries as to the identity of the J. Reynolds, who, nearly three weeks previously, had deposited a bag in the cloak-room of Liverpool street station.

In company with a detective, whom he had borrowed from Scotland Yard, he had called at the cloak-room that afternoon, but beyond taking possession of the bag that had not been called for, he had not obtained much to help him.

The cloak-room attendants had not any recollection of the individual who had deposited the bag with them, and that was easily understood, considering the great number of parcels, packages and bags, &c., that were left there every day.

Larose had brought the bag away, arguing that the mysterious Mr. Danker, not knowing where he had dropped the ticket, would not dare to run the risk of calling for his property, and arguing, too, that if he had been intending to claim it, then he would have done so days and days ago, and not allowed so long a time to pass by. As a precaution, however, instructions had been left with the head clerk of the cloak-room that if, by any chance, any person should come about the bag and state he had lost the ticket, then he was to be held in conversation while one of the railway policemen was being summoned to detain him until Scotland Yard had been communicated with.

But Larose was building no hopes there. "This man is wanted for something much too serious," he told the cloak-room officials, "and it is any odds against his turning up."

So now he had the bag and its contents spread out before him and, with his life's training in the picking up of clues, was endeavoring to determine from them the apparent occupation and habits of their owner.

"And where he lives," he grinned. "Where's his hiding place in London, and where he's been carrying this bag to and fro."

He enumerated the articles before him. "A bag, a cap, a coat, and from the pockets of the coat, a key, a portion of a slab of Fry's Mexican chocolate, and some glycerine lozenges in a packet labelled Westbury, Chemist, Bromfield street. Hum! not much to go upon, but still things might be worse!"

He scrutinised the bag closely, examining it from every angle. "A good class bag, not a cheap one, and therefore I may presume its purchaser was not a needy man. Undoubtedly, its greater service to its owner has not been upon rail or motor car journeys, because it has been carried so much in the hand. The under-surface of the handle is smooth and shiny, and besides, I can see most plainly where the side of the bag has been continually rubbing against his clothes as he has walked along. He is a right-handed man, and has been carrying it about with him for quite a considerable time."

He examined the outside of the bag with a big magnifying glass and went on. "It has been deposited in cloak rooms scores and scores of times, as evidenced by the paste marks and still adhering edges of many torn-off dockets. I can count 27 of these edges, distinctly, and they are of varying degrees of age, from quite recently to long ago. From the swatches on the plate, the lock has had the key turned in many times."

He summed up as far as his thoughts had led him. "Yes, some man has been carrying this bag about very often, and if the hour he deposited it in the cloak-room this last time is any indication of his daily routine, then he is not in the habit of taking it with him to the place where he sleeps. The number upon the docket showed it was issued quite late in the day, upon that Tuesday, September 17, with 704 dockets before it, and only 47 to follow."

He nodded. "So, I will assume his general custom was to deposit it in some cloak room when his days work in the city was done and, taking a long shot, I should guess this coat and cap were changed in some toilet convenience for something more suited for the place where he actually lives. This coat was surely his working coat, and both it and the cap were in accordance with the nature of the work he was engaged upon during the day."

He went on. "Now for the coat itself. Ready-made, but of good quality, indicating once more that the man was not poor. Lining of ticket pocket quite clean, with its flap still almost straight. That means that he apparently did not use the ticket pocket at all, and therefore that he did not have to take a bus, or tram or another train from Liverpool street, to finish his daily journey suggesting, of course, that his work lay not far away. Lining of side pockets pretty clean, and that shows that they were not used much. But lining of breast pocket is shiny and was therefore used much more. It bulges quite a lot, too." He sniffed hard. "Yes, it smells strongly of cigars and so he undoubtedly carried a cigar case there, as well, perhaps, as a wallet."

He sniffed again. "No, that coat does not smell of cigars, and therefore its owner smoked his cigars at either or both ends of his journeys to and from the cloak room, and when he was wearing a different garment." He thought for a moment. "That's interesting, for this coat, then, undoubtedly the property of that man Danker, an inveterate cigar smoker, can hardly have been worn at all except upon these daily journeys. Therefore, it is most probably a link between two personalities, the personality in which he arrives at some cloak room to claim his bag in the morning, and the personality he assumes at the other end of his short journey, when he starts upon his day's work. That he was not remembered an Liverpool street station is of small moment, for he may not go to the same cloak-room every time. There are plenty of other railway stations close near. Broad street, Moorgate street, and the stations on the Underground and the Tube."

He continued. "Now for the key, a Yale lock one, with its number filed away, and filed away so deeply that no chemicals or enlarged photo shall by any chance bring up the imprint of the figures of its number. That alone is suspicious and proves the man is upon some shady business, and did not intend, if he lost it, that the particular lock it fits should be traced by the records kept by the Yale Lock Company. The key is a front-door key, or rather, seeing that it is used in the City, it probably opens the door of some office or room in some building."

"Now for the glycerine lozenges bought at the chemist's in Bromfield street! They may certainly furnish some idea as to the direction in which he is accustomed to go after leaving Liverpool street. Then this packet of chocolate may indeed be of greater help, for as an habitual consumer of chocolate, it is quite possible he may occasionally purchase his packets at the same place, and so, perhaps, in some sweet-shop in the neighborhood of Bromfield street, someone may remember a customer who comes in, carrying this bag, and wearing a cap like this."

He nodded again. "Yes, with any luck that's how I'll pick him up to begin with. So, to-morrow I'll go the round of all the sweet shops, wearing this cap and carrying this bag. Unhappily I cannot wear the coat, too, because it is too big, and would make me look conspicuous."

He leant back in his chair and shut his eyes tightly. "Now let me think. Let me start off quite clear." He spoke very slowly. "Now if I knew nothing of what had gone before, what should I take the owner of the bag and coat and cap to be? A commercial traveller, undoubtedly, and one who tramps round and round in some one particular district! As I say, he has carried the bag about quite a lot, and not using his ticket pocket, then he has apparently not boarded trains or buses whilst doing so."

He screwed up his face. "But he has not carried many samples or articles in the bag, for its lining is very clean and its sides have never been distorted and bulged out of shape." He sat up in his chair with a jerk and opened his eyes very wide. "Then what the devil does he travel in? Ah! but another thing—a commercial traveller would not be going about in a cap and a coat like this. He would be making himself look much smarter." He shook his head. "No, I should undoubtedly be wrong there. He is not a commercial traveller, and for the same reason he is not a clerk in an office. His occupation is a lowly one, but at the same time it is one that does not involve dirty work, for the sleeves of his coat, about the wrists, are not soiled or greasy, in any way." He shook his head again. "I give it up for the present."

His eyes brightened. "Now comes another problem. This man Danker, this toothless old man, this J. Reynolds with the bag cannot be Mitter, for the butler has informed the Secret Service people most positively that Mitter was not absent from Dunwich when Scampy was making history with the Mary Belle, and yet"—he screwed up his face again and spoke most emphatically—"after all I've heard about Mitter from Mr. Grant, and after finding out that Mitter is the son of that Mangans, the spy, and knowing Mitter as I do myself, I'd swear it was Mitter himself who was on that Foulness job."

He shook his head frowningly. "Yes, the very audacity of it would be just like Mitter! A man of his known nationality; openly and boldly making friends among the Service, as he does, and talking affably and easily the other day to Sir Hubert Carnarby and Colonel Bevan, when he must have been quite aware from the spying he is doing, that they are in the Intelligence Department!" He chuckled with some amusement. "Perhaps, too, he even knew who Mr. Grant was, for a man of Mitter's capacity would find out a great deal, and most certainly not be the innocent the British Secret Service have believed him to be."

His thoughts ran on. "Besides, Mitter smokes strong cigars, just as that Danker did, and I make out from the descriptions given by Rook, Colonel Maitland and that sergeant on Foulness, that the build of that toothless old man was exactly that of Mitter when you square the shoulders and take out the slouch. Another thing, too. Scampy said Danker, whoever he was, was no common and uneducated man, but had the bearing and manners of a gentleman. And Scampy should know a gentleman when he sees one, for when in the Force he was attached to the Marlborough street police station." He thought for a moment. "And Mitter's gentlemanly bearing is the first thing that impresses everyone when they are introduced to him."

He looked very troubled. "Yes, that butler's testimony is the snag that worries me, and I'll have to have a talk with him as soon as it can be arranged. He certainly doesn't look intelligent enough to be double-crossing us, but I must give him a good look over, with that possibility in my mind."

He thought on for a long time and then heaved a big sigh. "But it's bed now, Gilbert, and then to-morrow you'll go tramping all round Bromfield street, buying lollipops or chocolate at every sweet shop you go into."

So, the following morning saw Larose alight from a bus at Liverpool street station, wearing the cap of J. Reynolds and carrying the latter's bag. This time he was accompanied by no detective from the Yard, for he was intending to rely upon what he considered a much more powerful ally, a crisp £5 note for anyone who could furnish him with the information he wanted.

He looked in at Westburys the chemist's, but the proprietor and three assistants there only smiled and looked very amused at his enquiry. They had no habitual purchaser of glycerine lozenges, and remembered no individual with that particular cap and bag.

Then he began the round of all the shops selling Mexican chocolate, and although many pairs of eyes gleamed when the £5 note was produced and promised, he got no satisfaction from anyone, and lunchtime found him partaking of a grilled chop in the refreshment room of Moorgate Street Station, in a very dispirited frame of mind.

"You've now twenty-nine packets of Mexican chocolate in this bag, my boy," he grinned, "and by nightfall it will probably run into a hundred. The family will be kept in chocolate for a year."

But as it turned out he was quite mistaken there, for at the very first shop he went into, when the luncheon rush was over, he got upon the trail of the man he wanted at once.

The shop he entered was a very small refreshment one in Fore street, just round a corner and to the side of the entrance to a big building of many offices. It consisted only of two small rooms and a cellar, and sold ginger beer and lemonade, sandwiches, cakes, oranges, and a general assortment of confectionery. It was kept by two sisters, middle-aged spinsters, very obliging and very intelligent-looking. They were alone together in the shop when Larose went in.

Yes, they had one particular customer, they said, who occasionally came in to buy Mexican chocolate, and they remembered him because he always bought five one shilling packets at a time. No, he did not come regularly, and, indeed, had not been in for some time now. Still, he might come again any day. When he called, it was generally early in the day, about ten o'clock. Yes, he carried a bag like that, and wore the same kind of cap, pulled down low upon his forehead. He always had gloves on, and wore dark spectacles. He was clean-shaven, of medium height, and looked about forty. He was a very nice man to speak to, and always very polite. No, he did not look a clerk, besides a clerk would have to get to his work before ten o'clock. They really did not know what his work might be, but he was certainly not a working man. He had a superior air about him.

Larose at once proceeded to produce the page of the 'Sphere' that he had shown to Scampy, and asked the sisters if they could pick out, in the photograph taken at the Brandon coursing meeting, anyone at all like their chocolate customer.

The sisters stared hard, and then one of them said hesitatingly: "He might be several of those gentlemen, but, of course, they're all much better dressed," and as before when he had shown the photograph to Scampy, Larose felt very disappointed.

He look out a £5 note and handed it across the counter. "Now, here's five pounds to begin with," he said impressively, "and if, when that man comes in again, one of you follow him and find out where he goes, it'll mean at least £20 to you, for I want to get his address very badly."

The sisters looked rather frightened. "But what's it all about, sir?" asked the elder of them with a catch in her voice. "We don't want to be mixed up in any case in the police court."

"And you won't be," laughed Larose merrily, at all costs not wishing to upset them. "I tell you honestly I've nothing whatever to do with the police, for I'm only a private detective, and if you find out where he goes, your names will never come out."

"But what's the poor fellow done?" asked the other sister. "He looks such a nice man to us."

Larose fibbed boldly. "He's not a nice man," he said sharply. "He's married to a very pretty young girl and the poor thing's just got a baby, but he's left her to go off with someone else." His voice took on an indignant tone. "He's got a bit of money, but he's left her quite destitute."

Indignation, too, thereupon at once seized the sisters, and the expression upon their faces changed from fear to disgust.

"Then I hope you get him and make him pay for it," said the one whom her sister had addressed as Hetty. "Some men," she added, "are horrid creatures, and we're always glad we never married."

A few minutes later Larose bade them good-bye, after receiving from them the solemn assurance that one of them would certainly follow their customer the next time he came in and then immediately telephone up a message to the number he, Larose, had given in Pimlico.

"You can depend upon us," said Miss Hetty in parting. "We've got all our wits about us, and the £20 will be a perfect God-send, for trade, lately, has not been very good."

Larose was very satisfied with the way things were shaping. "Things couldn't be going better," he told himself that night, as he was treating himself to a nice little dinner at the Savoy, "and I'll run that chap to earth, sure enough." His face clouded. "But it may be a long wait, and I'll have to kick up my heels here doing nothing and just marking time. I'll have to wait in every morning, too, until well after half-past ten, and never, indeed, be far from a phone at any hour of the day." He shook his head. "But patience, Gilbert, patience! You've had to go slowly many a time before."

Happily, however, for Larose's restless nature, he had not to wait very long, for upon the third morning, exactly at ten o'clock, the long-hoped-for message came through on the phone.

It was the sister, Hetty, speaking, and she said the man had called in at the shop not ten minutes previously. She had followed him and seen him go into Moon Buildings, upon Finsbury Pavement!

Instantly Larose became all activity, and, much less than an hour later, made up as an old gentleman, was interviewing the two sisters in their little shop in Fore street.

The man had looked very much as he had done before, they said; was wearing a cap of similar type, and was carrying a bag of about the same size as the one before. The bag now, however, was a new one.

"But we can't be certain, sir," said Hetty finally, "that he's like any of the gentlemen in the photograph you showed us. He's something like their style, but I am sure I should never pick him out of that group if someone didn't suggest I might find him there."

"Never mind about that," said Larose cheerfully. "But tell me, now, did he go into the building as if it were his habit to do so? I mean, did he walk in without any hesitation?"

"Oh, yes," was the reply. "He went straight in, and I saw him nod a sort of good-morning to some man in uniform who was standing just inside the entrance."

"That's splendid," said Larose. He frowned. "But you don't think he saw you were following him?"

Hetty shook her head. "No, I'm sure he didn't. He never looked round once, and he walked quickly as if he were in a hurry."

Larose handed over four £5 notes to the delighted sisters, with the remark, however, that he might still, perhaps, be wanting their help.

"It all depends upon whether I am able to recognise him," he said. "If I can't, then I'll have to get one of you to come and wait somewhere near the entrance one morning, and pick him out for me."

His next move was to pay a visit to Moon Buildings, and he walked in confidently as if he had some business with one of the tenants and knew exactly where to go. He passed a big brass frame, with its scores of numbers and names, with just a slight side-glance and took no notice of the attendant who was standing by his open lift.

"Hm!" he remarked thoughtfully, "that's probably the chap he nodded to, and if I only dared to risk it, the whole business would be a very simple one." He shook his head. "But no, I must find out first what sort of fellow this lift-man is. A man like Mitter, or indeed any man engaged upon the same kind of work that he is, would be suspicious of everyone, and if I now go asking questions of this fellow, however high I may bribe him, his face may give him away at once, the next time my fine gentleman sees him."

He traversed the whole length of the passages upon the ground floor, noticing with some annoyance, the other entrance into the building. Then he walked up the staircase and along every floor scrutinising all the names upon the office doors. Finally, he descended from the sixth floor, in the lift along with some other passengers and left the building by the Fore street entrance.

He next proceeded to the refreshment room in Moorgate street station, and over a large cup of black coffee and many cigarettes considered what he must next do.

"No, I can't go nap on that lift-man," he told himself. "He's too curious and too chatty and, as I was afraid, would give the show away at once. It wants a man with a poker face for this job."

He thought for a while. "And I can't spring the trap yet, for I may find I've got only a very small mouse in it or even none at all. I must see this man for myself first and find out, too, what is his ostensible occupation here." He shook his head vexatiously. "He can't possibly be Mitter after what that butler says, which is a deuced nasty fly in my poor little pot of ointment. He may not even be J. Reynolds, Danker, or that toothless man. He may be quite a different person altogether, and then—" he sniffed scornfully—"shouldn't I be done?"

He went on. "Besides, who's going to identify J. Reynolds. There's no one to identify him." He nodded.

"Yes I must go slowly, and carry on on my own. I must trail that chocolate man when he goes home tonight." He looked uneasy. "But shall I recognise him? That's the difficulty. There are plenty of men with caps and bags and he may not even carry his bag tonight. Again, he may leave the building by the other entrance, or, Great Scott!" his face fell—"he may even have gone off by now!"

He lit another cigarette and reviewed everything calmly. "Now the position is this. The Secret Service people know for certain that Mitter is spying over here on behalf of his country, and they are of opinion now that the work carried on from Dunwich Hall is only a blind. They think his real work is being done from another place. Well, connecting Mitter with that Southend newspaper, connecting that newspaper with Danker's exploits on Foulness, and Danker with J Reynolds, and J. Reynolds with Moon Buildings—I think I've found the place. Good! Then the job is to connect J. Reynolds with Mitter and the circle is complete. I'll set about it at once in a practical, commonsense way, taking no risks of frightening anybody by injudicious enquiries that might possibly come to their ears and cause them to bolt away."

Larose was a quick worker, and once having made up his mind about anything, he never allowed the grass to grow under his feet. So after having hung about the entrance to Moon Buildings until well after five o'clock, and failing altogether to pick out anyone leaving there who looked at all like Carl Mitter, he at once proceeded to take more practical and energetic measures.

He went into a building almost opposite, and after some persuasion and the offer of a stiff rental, paid in advance, secured the use of one of the rooms of a typewriting bureau for a fortnight. The room was upon the fourth floor, and its window faced the street. He told the proprietor of the bureau, quite frankly, that he was a private detective and wanted to obtain a photograph of certain parties who would probably be passing in the street below in the course of the next few days.

So the following morning, at half past nine, found him installed in the room, in company with an expert photographer, with a large camera fitted with a telescopic lens, and Miss Hetty from the sweet-shop. The three of them were occupying chairs close to the window, and Larose and the woman were provided with powerful glasses.

Miss Hetty was all in a twitter of excitement, and, now embarked upon the adventure, enjoying herself immensely. She was sure, she declared, she would be able to pick out their customer at once, whether he carried a bag or not.

But no good fortune came to them that day, although several times Miss Hetty started from her chair, thinking that the great moment had at last arrived, only, however, to sink back again, disappointedly, declaring herself to be mistaken.

"Never mind," said Larose cheerfully, when at half-past five they all prepared to go their different ways, "we may have better luck to-morrow. Perhaps he doesn't come up to business every day." He laughed. "Besides, the longer he takes to put in an appearance, the more you will both have to be paid."

The next morning they were all together again, just before half-past nine, and they had something to interest them at once, for a telephone mechanic, swung in a slender cradle, began to pull himself along one single strand of wire, suspended high above the street. Everybody passing along was interested, too, and all heads were turned up to watch his seemingly perilous journey.

"But keep your eyes on the pavement, please," cried Larose sternly, "for, remember, this is the most likely time for our man to appear."

And it was well he had warned them, for not half a minute later Hetty jumped up excitedly, calling out. "There he is, just by that red motor car. Look, that man carrying the bag. Quick, he's stopped and is staring almost right up at us."

But there was no hurry, for the man's gaze was fixed intently upon the mechanic in the cradle, and the photographer was enabled to make three good exposures, before he turned away his face and proceeded up the street. Then the excited watchers saw him go straight into Moon Buildings.

"Are you sure that was the right one?" asked Larose sharply, disappointed that with his dark glasses and the cap pulled down low upon his forehead the man had not appeared to bear much resemblance to Mitter. Added to that, the man had not seemed to be quite so tall.

"Quite sure," replied Hetty, struggling to get back the breath that had all left her in her emotion. "There's no possibility I can have made a mistake."

"Then you remain here on the watch," said Larose briskly, "so that we can be sure he's not come out again. We'll be back again in less than an hour," and he rushed off with the photographer to get the plates developed.

But good fortune was no longer smiling upon Larose, for returning well within the specified time of one hour, Miss Hetty, almost with tears in her eyes, informed him that the man had come out of Moon Building again, not ten minutes after they had gone away.

"It doesn't matter," smiled Larose, apparently in no wise disappointed. "We can't have it all our own way and, at any rate, we know that our friend continues to come here and that's the main thing. It will be only a matter of days now before I have my little talk with him."

That night Larose was sitting again in his lodgings in Pimlico, holding in his hand one of the photographs taken that morning.

"It's disappointing," he frowned, "but the idea is not so unlikely that I can give it up altogether. It's got Mitter's chin and he's holding himself as Mitter does, but the nose and the mouth and the general shape of the face are quite different." He scowled. "The deuce take those glasses! If only I could see his eyes!" He shook his head. "And another snag. Mr. Grant is positive that if Mitter were away from home today the butler would have rung up Saxmundham, and yet no call has come through. He says the butler has never failed them in that respect." He shook his head again. "It's puzzling and I can't understand it."

He returned the photo to it's envelope and put it in his pocket. "Well, I'll carry on on my own for the present," he continued, "but the darned trouble is I can't go up and speak to him, for if he's Mitter, at close quarters, he'll see through my disguise at once."

The next morning, still made up as a prim old gentleman, he lounged about in the vicinity of Moon Building and then, suddenly, things began to happen very quickly, for without a moment's warning he came almost face to face with the man he wanted. The latter was walking briskly along looking neither to the right or left, and carrying the incriminating bag with him.

Larose, daring to bestow upon him only one lightning glance, followed cautiously after him and then when the man turned into the entrance of Moon Buildings, he quickened his pace so that he was almost upon the heels of his quarry, as the latter entered the main corridor.

He saw him turn his head and without stopping, nod good-morning to the lift-man, but then before he could see whether the man continued up the corridor or took to the stairs, he was violently bumped into by a hurrying messenger boy and thrown completely off his feet. He sprawled to the floor with all the wind knocked out of him.

For the moment he was quite dazed, but the lift-man ran up and helped him to his feet.

"Just like those darned boys, sir," he exclaimed viciously, "for they never look where they're going!" He began to brush down Larose's trousers with his hand. "I hope you are not hurt, sir."

"No-o," gasped Larose, beginning to get back his breath, but in a fury of mortification, for he could now see no sign of the man he had been following. "I'm-quite-all-right-thank you. It was Mr."—he glanced up at the frame upon me wall and took the first name that caught his eye—"it was Mr. Staines I was running after. That was the gentleman who just said good morning to you, wasn't it?"

"No that wasn't Mr. Staines," replied the lift-man. "That was Dr. Smith's man. Do you want him?"

"No, no!" exclaimed Larose hurriedly. "It was Mr. Staines I wanted. I thought it was he."

"Well, I'll take you up in the lift to Mr. Staines's, sir," said the lift-man. "His rooms are on the fifth floor, and it's a long way to walk up."

So in a few seconds Larose was ascending quickly to the floor where this Mr. Staines, whoever he was, carried on his business. The lift-man was disposed to be very chatty.

"Good reliable man, Mr. Staines, sir," he remarked. "Even one speaks well of him, and he does a good business. Here we are, and that's his office right opposite. Harry, Harry," he called out sharply as the lift stopped, and he caught sight of a young fellow through an open doorway. "There's a gent wants to see the boss." He stood aside for Larose to walk out of the lift. "This young chap will attend to you, sir."

Larose cursed under his breath. He had not the remotest idea what excuse he could give, and yet, without exciting suspicion, he could not now decline to enter the office. Then to his great relief he caught sight of a small brass plate upon the wall near the office door. 'George Staines, Patent Agent,' he read, and he grinned to himself at the thought of the farce he would now have to play.

The clerk motioned to a chair. "Mr. Staines is engaged at the present moment, sir," he said, "but I don't think he will be long," and Larose was quite pleased, for it would give him time, he thought, to imagine some kind of invention, about which he wanted to know the cost of taking out a patent.

But he was not by any means pleased when the minutes ran into half an hour, and he could still hear the hum of voices in an adjoining room. Then, the time extended to three-quarters of an hour, and in the end nearly a whole hour went by before he was finally ushered into the presence of Mr. Staines.

He apologised for taking up Mr. Staines's time he then explained, and said he had thought of an idea for a new kind of corkscrew, and wanted Mr. Staines to inform him how to set about getting it patented. Thereupon, the obliging Mr. Staines proceeded to go fully into details, and it was quite another quarter of an hour before Larose could get away, with the promise made of calling again another day.

"I'll send him a postal note for a guinea," he told himself as refusing the offer of the clerk to have the lift rung up he proceeded to make his way down the stairs. "It's a shame to have taken up his time for nothing."

Remembering then that the man he was after had not taken the lift when coming into the building, he was sure that Dr. Smith's consulting room would not be very far from the ground floor, and with no very clear idea in his mind as to what exactly he was going to do when he found it, he commenced his search upon the lower floors.

Then with his heart palpitating a little he had just caught sight of 'Dr. Smith. Diseases of the Skin' upon a brass plate upon a door numbered nine, at the end of the passage on the first floor, when he heard a loud voice, the door itself opened, and a stout man with a red and blotchy face came bustling out.

"Good-bye, then Doctor," called out the stout man. "I'll try it for another month," and Larose heard a hoarse voice say in return, "Good-bye, Mr. Jennings," and was just in time to catch a fleeting glimpse of the dark-spectacled and well-bearded face of a white-gowned man, inside the room, as he passed the doorway.

"Ho! ho! then I've seen Dr. Smith," he chortled, "and so at any rate I've not had all my trouble for nothing."

Walking very slowly, he allowed Dr. Smith's patient to go past him, and then, an idea seizing him, he followed the stout man into the street.

"Now if by any lucky chance I could get a word with this gentleman," he went on, "I might learn something of this doctor's habits and be able to get into his rooms when he and his man are away. He's got four rooms, I see, and this key I've got will almost certainly fit one of those doors."

And he did get the chance, for the stout man, after looking in a shop window or two on his way, turned into the bar of the Talbot Hotel.

Larose followed after him and standing by his side, as an encouragement to conversation, ordered, as the stout man had done, a large rum and raspberry.

The stout man made a nod of approval as he heard the order given and smiled socially. "Good stuff in this darned weather!" he remarked with a shiver. "Keeps the cold away!"

Larose agreed with a returning smile, and then lowering his voice, said apologetically. "Excuse me, sir, but wasn't it you I saw just now, coming out of Dr. Smith's consulting room in Moon Buildings?"

"Yes, it most probably was," replied the stout man with no surprise, "for I've been to see him this morning." He wrinkled up his blotchy face. "Do you know the quack, too?"

Larose shook his head. "No," he hesitated, "but as a matter of fact I've been thinking of going to see him for some time."

"Then think better of it," growled the stout man with a grimace, "for I can tell you he's not up to much." He took a long pull at his rum and raspberry. "At any rate he's done me no good."

"Oh, then I'm so glad I ventured to mention it," exclaimed Larose gratefully. "It'll save me wasting a guinea, at any rate."

"Guinea be blowed!" scoffed the stout man. "He charges two every time you go in, and it's precious little you get for your money." He pointed disgustedly to his blotchy face. "I've been to him to cure this, and all he says is 'Rub on Zinc Ointment, wash it with oatmeal, and drink a lot of water!'" He scoffed disgustedly. "I'm not going to give any more good money to be told the same damned thing every time. I can yap that to myself, without it costing me another penny."

Then Larose drew out skilfully quite a lot about the doctor's habits, how he never kept regular hours and how it was never certain he would be found in his consulting room two days together; how he always talked so quietly and in such a hoarse whisper that no one could hear half he said, and how he always seemed to be in a hurry and wanting to fire everyone out as quickly as possible. He also learnt, when the doctor bent over you, he always smelt of some 'chemical muck' and that he always wore rubber gloves. There was no nurse or attendant that the stout man had ever heard of, or had ever seen.

Larose treated his confiding informant to another rum and raspberry, considering the information he had gained very cheap at the price.

"Now I must find out straightaway," he told himself, "whether this doctor's man is Mitter or not, and if he isn't, I'll make some excuse and go to consult the doctor myself, to-morrow, for whatever dirty business they are up to, the two must be in it together."

He went into the Liverpool street Station Hotel and informed the young woman at the desk that he was lunching there, and asked her to kindly put through a trunk call for him. He gave the number of Carmel Abbey and said he would wait in the lounge until the call came through.

He was soon summoned to the phone and, speaking to his wife, told her he wanted her to find out at once if Herr Mitter was at home. She was to ring up Dunwich Hall and ask Mitter if he would come to dinner one night next week, but on no account was she to let Mitter know that he, Larose, was in town.

Less than a quarter of an hour later Mrs. Larose rang up and gave him the information he wanted. Mitter was at home, and she had spoken to him. The butler had at first been very reluctant to fetch his master to the phone, because the latter, he said, was very busy painting in his studio, and at such times never liked to be disturbed. Mrs. Larose had, however, made him take in a message and then Mitter himself had come to the phone. Speaking very hoarsely, he had thanked her for the invitation, but had said he didn't think he would be able to accept it, because, at present, he was suffering from a very bad cold.

The following morning, looking now quite different to the old gentleman of the day before, Larose was waiting near the entrance to Moon Buildings by half past nine. He had inflamed the palm of his left hand with a mustard leaf and was intending to consult the specialist in diseases of the skin as to what was the matter with it.

The day was bitterly cold and inclined to be foggy, and, stamping his feet to keep himself warm, Larose devoutly hoped it would not be long before he caught sight of the man with the bag, or his master.

Ten o'clock came, half past, and then eleven, and with no appearance of either of the two he wanted, Larose began to think it must be the doctor's day off. But he was not going to be wholly disappointed if neither of them did turn up, for in that case he was intending to take a risk and see if the key he had found in the coat pocket would gain him admission into the doctor's rooms.

But he must first be quite certain, he told himself, that the doctor had not arrived, for it would never do to be caught red-handed trying to open one of the doors. He must leave nothing to chance there and take into consideration the possibility that either the doctor or his man might have come into the building through the other entrance.

He waited until half past eleven, and then, neither of them appearing, he entered the building, intending to enquire of the attendant on the lift if the doctor were consulting that morning. If he were told the doctor was not there, then he would leave by the main entrance, but return again through the Fore street one and make his way up by the stairs.

With this end in view, he was approaching the lift, which had just come down and was discharging several passengers, when a tall and elderly woman thrust herself before him and demanded of the lift-man in a very shrill tone of voice if Dr. Smith had arrived yet.

"No, mum, I don't think he has," replied the lift-man, "for I took a gent up, not five minutes ago, and he wasn't there then. Besides, I haven't seen his man go up this morning, and he always comes half an hour before the doctor, to get the rooms ready for him." He made a motion with his arm towards the lift. "Still, he may have come in by the other entrance, or I may have missed him when in the lift. So we'd better go up and see."

"It's most annoying," complained the woman as she prepared to enter the lift. "I'm a new patient and I've come all the way from Beckenham to see him." She nodded vigorously. "But I've heard he's like this and that you never can be certain he'll be here."

The lift disappeared, and Larose moved off a little way down the corridor to wait and see what would happen, without being observed. He had not long to wait, for the lift came down again almost at once, and he heard the woman again talking volubly. "Well, I'm not going away yet, although you do say you don't think he's likely to come now. I'll wait down here and go up again in a minute or two. It's most annoying there are two entrances to this building!"

Then Larose did not hesitate a second, but proceeded to run quickly up the stairs.

"Now's my chance," he breathed exultingly, as he gained the suite of chambers occupied by the elusive Dr. Smith, "and with any luck I'll soon learn something about him and his mysterious man."

He inserted his key in the lock of the door, with 'Waiting Room' painted upon it. The door opened at once, and, with a quickly-beating heart, he stepped into the room and closed the door again, softly, behind him.

CHAPTER IX
RUN TO EARTH

LAROSE wasted no time in taking in the scanty furnishings of the waiting room, but tip-toed quickly through a half-opened door, into what, he knew at once, must be the consulting room, because of the desk, the microscope and the row of dusty test-tubes in a rack upon the mantel-shelf.

But for the moment he gave only a swift glance round, and then he darted to another door that he saw led into a much smaller room. Then, with noiseless steps, he was back again in the waiting-room and finding out where the fourth room led.

He wanted to be able to cover his retreat if he should hear anyone coming and was looking for some place to hide.

"Caught like a rat in a trap!" he frowned with a rather scared face. "Not a thing to creep behind anywhere. There's no hope for me if either of them come, and I'm taking a terrible risk."

"The consulting-room first," he whispered, as he ran back, and in two seconds his hand was in the letterbox that he had noticed was affixed there to the door from which he had seen Dr. Smith show out his patient the previous day.

He drew out four letters and his eyes glinted as he saw the postmarks upon them. "Glasgow, Portsmouth, Chatham, Burnham-on-Crouch!" he ejaculated. "Great Scott! but it looks a sure thing!"

He thrust the letters hurriedly in his pocket and turned next to the big roll-top desk. Then he felt the blood surge into his face and a sudden pumping of his heart, for upon the rug under the desk-chair lay a small bunch of keys.

For the moment he could hardly breathe in the excitement of such good fortune, but then, swallowing hard, he took a good grip of himself, his pulses calmed down and his face became as impassive as that of the Sphinx. The room was darkening quickly, for the fog outside was becoming denser every moment.

There were only four keys on the bunch and the one to the desk was easily picked out. He unlocked the desk and rolled back the top. Then his face puckered up into a frown, for his nostrils were immediately assailed with an ether-like odor.

The desk was neat and tidy, and ignoring the contents of the pigeon holes, he proceeded to pull open the large drawers down the side. In the first one were maps, maps of every country in England, so it seemed; in the second were current copies of the Army, Navy and Air-Force lists; in the third were a number of cuttings from foreign newspapers and in the fourth—and the eyes of Larose almost started from their sockets as its contents came into view—were a pair of rubber gloves, a large wig, a full grey beard, a bottle of collodeon, and a pair of big dark glasses.

"What! what!" he gasped incredulously, with his month dry and his heart thumping like a piston, "then this doctor attends his patients in disguise. These are the wig and beard that he was wearing yesterday!"

For a moment, then, the significance of his discovery seemed to paralyse all his actions, and with gaping mouth he stood staring at the wig he was holding in his hand.

"But it can't be true," he whispered hoarsely, "and yet it must be, however incredible it seems. This doctor and his man are the same person! J. Reynolds with that bag is Dr. Smith, and he's been fooling everybody here all the time." His thoughts ran riotously through him. "Oh! Oh! But I begin to understand everything now."

Then, suddenly seized with an idea, he put on the glasses and the wig, and holding the beard in his hand, stepped over to a mirror on the wall. The fog was now making the light in the room so dim that he had to peer closely to see what appearance the disguise gave him. He held the beard up to his face to get the full effect. But then, apparently, not satisfied, he darted back to the drawer of the desk, and, opening the bottle of collodion, quickly moistened round the edges of the beard and placed it in position.

"And that's what my stout friend meant," he went on breathlessly, "when he said the quack always smelt of 'chemical muck.' It was this ether solution he was smelling." He stared at himself in the mirror. "Oh! How easily I could impersonate the doctor!"

Then suddenly he almost jumped out of his skin, for the bell of the waiting room door buzzed loudly, and the handle of the door rattled as someone tried to enter.

With his finger to his lips, Larose turned sharply; so sharply, indeed, that he knocked over a chair and it fell among the fire-irons in the grate with a resounding clatter.

Thereupon, whoever was outside the door began to rap loudly with his knuckles, and a gruff voice called out, "Carrier here. Parcel, if you please."

Larose felt a sickening feeling at the pit of his stomach, for he realised on the instant that he must open the door, otherwise the carrier might return downstairs and inform the lift-man that he had heard someone moving about inside the room, and yet no one had come in answer to his knocking.

So snatching up a long white coat that he saw hanging on the back of a chair, and hunching up his shoulders as the rum and raspberry man had told him the doctor always did, and prepared to speak only in a hoarse whisper, with a prayer of thankfulness for the darkness of the rooms, he shuffled over the floor and opened the door.

"Parcel for Brown and Brown," grunted the man in the corridor crossly, as if he were annoyed at having been kept waiting, and he thrust forward his cart-book. "Sign here!" he went on. But then, before Larose had had time to take the pencil he was proffering, the man, after a quick start, moved back a couple of paces to glance up at the number on the door.

"Oh! I beg your pardon, sir," he exclaimed apologetically, and now in quite a different tone. "I see I've come to the wrong rooms. It's Brown and Brown, the auctioneers, I want, number six, first floor. Very sorry to have disturbed you," and with a great thankfulness upon the part of Larose, the carrier moved off back along the corridor.

But the thankfulness of Larose was short-lived, for before the man had gone five yards a shrill voice came loudly—"Dr. Smith, isn't it?" and the voluble, elderly woman of the lift of a few minutes before, almost jumped into the doorway.

Larose heaved a sigh that came almost from his very boots, but forging a reluctant smile, he resigned himself to Fate and bowingly invited the woman to walk in. All his life long he had been gambling with danger, but never, he thought, had he taken such chances before.

At any moment he knew the man with the bag might arrive, and then what was he going to do? Arrest him, knock him down, of course, hand him over to the police for impersonating a qualified medical man, and trust to the good fortune that had made him the master of Carmel Abbey, to continue her gifts! All life was a gamble, anyhow.

But then another dreadful misgiving seized him. What was this woman going to tell him she had got the matter with her, and what was he going to say? He was certainly in a most awkward position! Ah! but he would tell her. 'Zinc ointment, wash with oatmeal, and drink plenty of water.' Most simple and inexpensive treatment, and certainly it could do her no harm.

He ushered her into the consulting room, closing the door behind them, and motioned her to a chair in front of the desk, with a gravity that he thought becoming to a practitioner in diseases of the skin.

But before seating herself, the woman proceeded expeditiously to disrobe. She took off her hat and the fur choker round her neck, then her jacket, and placed them all upon the sofa. Then to his consternation she began unbuttoning her blouse all the time talking rapidly and in staccato-like tones.

"I've got a bad rash on my neck, doctor," she explained, "and it's beginning to spread lower down on to my chest. I've had it on and off for three years, and it irritates me most terribly. It comes on every winter, and it's always worse when I've been out. The cold seems to make it burn as if I'd rubbed mustard into it."

"Ah! hum!" remarked Larose very solemnly in a hoarse whisper. "Very distressing, I am sure! Yes very distressing."

"And I've been to our four local doctors," went on the woman shrilly, "and they haven't done me a bit of good. They say it must be nerves, and people often get it at my time of life."

"Yes, of course it is," snapped the woman. "It makes me feel downright ill. Look at the rash here!" and she exposed a generous expanse of chest for Larose's uneasy inspection.

"Ah! hum!" remarked Larose for the third time, and then catching sight out of the tail of his eye of a large magnifying glass upon the desk, he picked it up and proceeded to closely examine the inflamed area.

"Hum! Yes!" commented Larose, complying delicately with the request. "There's a lot of irritation there." He appeared to consider deeply. "Now has anyone else among your relatives ever had it?"

"No, we're all as healthy as trout. My father's eighty-two and my mother's nearly as old. I come of a good, clean-living family." The woman looked with some doubt round the room. "But can you examine it properly in the darkness here? Hadn't you better switch on the lights?"

"Out of order," frowned Larose shaking his head, "but I can see perfectly well, all I want to."

"Zinc ointment," replied Larose very solemnly. "Wash it with flour and drink plenty of water."

"No, no, ahem! With oatmeal, I mean," corrected Larose hurriedly. "It will do you a lot of good."

"But I've bought zinc ointment until I'm sick of the sight of its tins," went on the woman petulantly, "and it's done me no good."

"But it will with the oatmeal," nodded Larose. "That will make all the difference."

"And why do I only get it when I go out in the air?" asked the woman irritably. "The burning doesn't come when I stay indoors?" Tears welled up into her eyes. "Oh! it's making my life miserable, and I get so bad-tempered with everyone that my children must hate the sight of me."

Larose felt genuinely sorry for the deception he was playing, and then, really desirous of helping her, his detective instincts suddenly awoke.

"On cold days," corrected the woman tearfully. "Not on other days, not when the weather's warm."

"Then what do you do different on cold days?" asked Larose. "It must be something particular that brings it on."

"I don't do anything different," replied the woman, "except, of course to wrap up more warmly. I wear this thick jacket and my fur choker. I'm a bad one for the cold."

"Ah!" exclaimed Larose sharply. "You get it when you wear your choker. Now let me look at that choker, please."

The woman reached back and passed it over and Larose proceeded to examine it carefully. It was a cheap fox one and dyed a dark brown. Larose's eyes glinted.

Larose held up the length of fur. "Then, of course, this is your trouble, my dear lady," he exclaimed smilingly. "It's the dye in this fur that is irritating you." He chuckled in great amusement. "Don't you see how it all fits in? The rash comes when you've been out on cold days, when you've worn your choker. The rash has been troubling you for three years, and you've had the choker for three years!" He snapped his fingers together exultingly. "So that's all your trouble. It's as plain as day to me."

The woman's mouth opened wide with her surprise, but whatever remark she was going to make, was stayed by the interruption of noises that proceeded from the waiting room. The door there was opened with a bang, there was the sound of quick footsteps upon the floor, and then someone rapped loudly and insistently with his knuckles upon the consulting room door.

Larose had started from his chair and all the exultation had departed from his face.

"More trouble!" he breathed. "More trouble. But who the devil can it be now?" His pulse slowed down a little. "Still it can't be the man with the bag, for he wouldn't knock, and it can't be a patient either, for he wouldn't be in such a hurry." He felt the sickening feeling again in his stomach. "Oh! what I'm letting myself in for!"

But there was no hesitation in the way he moved towards the door and, from the expression on his face he was evidently prepared to be most annoyed at the newcomer's want of manners. He opened the door sharply and found a man, well muffled up in a long ulster, and holding a suitcase in his hand, just inside the waiting-room. The man put his finger to his lips and moved back a few paces as Larose appeared. Larose stepped forward and pulled the door to behind him, thanking heaven once more that the fog was making everything so dark.

"Sorry to interrupt you, Doc," whispered the man breathlessly, "but I'm in a terrible deuce of a hurry and have run all the way from the station. This cursed fog's delayed us and I've a bare half-hour only to catch my own train at Euston. I didn't really intend to call here, but I thought I should just have time."

He nodded vigorously. "You got the letter I put in the box yesterday, didn't you? Well, that's right. I just popped in to tell you I'd seen them off." He nodded again. "Good-bye, then, Doc, and don't expect to hear from me until I've properly settled in and then I'll let you know at once," and with a wave of his hand the man rushed from the room.

"Dear! dear!" exclaimed Larose, "and what did all that mean? Oh! if I had been able to ask him who he was!" He turned back to the consulting room door. "Now for the poor woman, and I must get her off, quickly, although she doesn't look the sort to be shifted in a hurry."

But he was most relieved to see that the patient had now buttoned up her blouse and resumed her coat and hat. The offending choker, she was holding in her hand.

"Oh! I'm so grateful to you, Doctor!" she exclaimed directly Larose appeared. "I'm certain you are right! I remember now, lending it one day to a friend of mine, and she thought she'd got nettle-rash afterwards. But, of course, no one put it down to this fur." She took out her purse. "Now, what is your fee, please."

But Larose, smilingly, waived her aside. "Wait, and see how you get on, first," he said. "Write to me in a month," and he opened the door for her to go out.

"But I haven't given you my name and address yet," she said, looking very surprised. "You don't know who I am."

"Ah! no, of course," nodded Larose, feeling rather sheepishly, but then taking down her name and address, he ushered her out, making light of her reiterated expression of thanks.

"Now for those other drawers," he whispered, when the door was closed behind her, "and I must be quick, for it's tempting Fate to remain here too long."

The contents of the first drawer on the side of the desk made him whistle. "Whew! an automatic with a silencer! By James! but it's lucky I didn't interview this doctor, and he came to suspect me!" He shook his head frowningly. "My word! this crowd must be a desperate lot, and will stop at nothing."

The contents of the other drawers consisted of cuttings from a number of foreign newspapers and, what rather puzzled him, a number of the leader pages of 'The Times,' neatly clipped together, and with their dates going back from the previous day to many weeks before.

The drawers examined, he glided into the small adjoining room and, with another of the keys, opened the safe. Then he whistled again, for he saw bundle after bundle of one pound Treasury notes done up neatly in elastic bands. Eleven of them, he counted, and making a guess, he reckoned they each one contained fifty.

He closed the safe and was just looking round to determine what else there was of interest when he again heard the sharp rap of knuckles, this time, however, upon the consulting room door.

"Gosh!" he exclaimed with his heart beginning to thump again, "and who the devil is it now?" He smiled a sickly smile. "Trades certainly brisk today."

He took a hurried look at himself in the mirror to make sure the wig and beard were all right and then opened the door.

"New telephone directory, Doctor," he said, "and I thought I'd give it you, as I was passing this way." His smile expanded to a grin. "Mr. Jasper's just been and he looked pretty sick when I told him you were here before him this morning. He's just stepped out to fetch some newspapers for you that he said he'd forgotten."

"Who's been?" asked Larose in a hoarse whisper, and thankful once again that the fog made everything so dark.

"Mr. Jasper," replied the man, and then, seeing that Larose had got his hand to his ear and was holding his head to one side as if he were puzzled and hadn't taken anything in he added, "Mr. Jasper, your man, Doctor."

Larose felt as it he were almost going to drop through the floor, but he managed to exclaim:—"Oh! yes, Jasper, of course. I'm rather hard of hearing this morning."

"And he looked quite ill to me," went on the lift-man. "His face went putty-colored as I was speaking to him."

"Yes, Doctor, he said he wouldn't be two minutes." The lift-man grinned again. "But he couldn't believe you had come, already, until I told him you had seen a patient and she had given me a shilling when she came down, because she was so pleased with what you had told her. Then, really, he looked as if he'd got the surprise of his life."

"Thank you, thank you," said Larose, taking the telephone book from the man's hand and preparing to push to the door. "I'm much obliged."

Then, alone in his room again, his heart palpitated so furiously that he could hardly get his breath.

"Oh! oh! what has happened?" he gasped. "The man with the bag has been back and hearing someone was up here, he's gone away again! He couldn't believe it and went putty-colored and looked ill! Good God! Of course he's seen the game is up and bolted!"

His thoughts ran on, and then in the flash of a second his nerves steadied, his pulse fell to calm and even beats, and his lips set in a firm straight line.

"Ah! but has he bolted? Has he thrown up the sponge so quickly, or has he gone to get help and is coming back here to put out my lights?"

The eyes of Larose glinted and he darted over to the drawer that held the little automatic with the silencer. He made sure that the pistol was loaded, tested the trigger to see that it pulled easily, and then put the weapon in his pocket.

Then, with a decisive movement, he picked up the receiver of the telephone upon the desk and gave Mr. Grant's private number at Whitehall. He was fortunate to get through almost at once and his words hissed into the mouthpiece, as he gave the secret pass word that had been allotted him.

"It's Larose speaking. Quick! I've trailed that man from Foulness and found his hiding place, although I'm half afraid he's bolted. Still, there's a lot to investigate here. Send three good men at once, the best you have, and one of them must be a fingerprint expert. Don't let them lose a minute. Tell them to come to Moon Buildings on Finsbury Pavement, room number nine on the first floor. They'll see 'Dr. Smith. Diseases of the Skin.' on a brass plate on the door. They are to come into the building, one at a time, and not ask any directions. Just come through the main entrance, along the corridor on the ground floor, walk up the stairs, turn to the right, and then it's the fourth door on the left. Knock once, scrape with the finger nails, and then knock again. I'll be waiting here."

He paused a few moments, as Mr. Grant methodically repeated the instructions that had been given, and then went on quickly:—

"But I don't think there's any chance now of catching the man we want red-handed, for unfortunately he got wind that a stranger had taken possession of his room, and he drew back, almost on the very threshold, just as he was coming in. But there'll be a lot here to interest you, anyhow. There are four unopened letters that came by this morning's post, and two of them are post-marked as coming from naval towns." His voice rose. "But, whatever you do, come instantly, for there's just the chance he may be returning with others to have a scrap with me."

"All right," came back the voice of Mr. Grant, even and very quiet, "we'll be with you in twenty minutes."

It was not half a minute after Larose had put back the receiver, when the telephone bell tinkled, and he started like a man stung by a hornet. Then he stood stock-still as if he had been turned to stone, and the expression upon his face was one of the most agonising perplexity.

What must he do, he asked himself, as his thoughts raced madly through his tortured brain, and his hand hovered hesitatingly over the telephone.

Was it the man with the bag ringing up to make certain someone was in possession of Dr. Smith's rooms, or was it one of his confederates who might betray information that would be of vital interest to the Secret Service? Or, again, was it only just a patient ringing up for an appointment?

But it was only for about five seconds that Larose hesitated, and then he lifted the receiver with a jerk, and purposely shuffling his feet about noisily, stood waiting for whoever had rung up to speak first.

He heard the sound of someone breathing heavily, but no voice came, and then a long, deep silence ensued. It was as if two adversaries were standing face to face, with each one waiting for the other to make the first move.

Quite half a minute passed, and then Larose realised that the wire had become dead!

He jerked the receiver back on to its hook and snatching up the telephone directory that the lift-man had just given him, began feverishly to turn the pages, to find out Dr. Smith's number.

It took him a long three minutes to pick out the Dr. Smith of Moon Buildings from the many pages of Smith's in the book, and then the receiver was back in his hand in a flash.

"Finsbury 278, speaking," he called out sharply. "I've just had a ring from someone who got through to me here, but wouldn't speak. He's hung up at his end, and I want to know who he was. I'm a detective from Scotland Yard, and the matter's of vital importance. Can you possibly tell me where the call originated?"

"I'm afraid not," began the girl at the exchange, and then she broke off suddenly. "Wait a moment, I'll see." Then almost immediately her voice came over the wire again. "Yes, you're lucky. Another operator remembers it. It was Finsbury 906."

"Thank you very much," said Larose. "Then put me on to Finsbury 906, as quick as you can, please," and in less than half a minute a deep gruff voice was saying. "Thomson speaking. Thomson, the tobacconist in Bishopsgate street."

Larose was all apologies, but explained quickly that he wanted to know who it was who had just called Finsbury 278 from their place.

"A gent who came in for some cigars," was the reply in brisk and business-like tones. "Don't know who he was and have never seen him before."

The tobacconist seemed uncertain. "O-oh! just ordinary, clean shaven, fair height, medium age, and wearing dark glasses."

"No, I didn't listen for him. I was busy with customers. He just asked me if he could use the phone at the end of the shop. He paid me the tuppence, and that's all I know. He was not by the phone, altogether, more than two minutes."

"And that's that," said Larose despondently, as he hung up the receiver. "We shan't see any more of him today." His face brightened. "Still, there must be a lot here that will tell us something."

Mr. Grant and three very alert looking assistants were soon upon the scene, and bidding the latter wait in the waiting room for a few minutes, Larose took Mr. Grant into the consulting room and briefly and quickly ran over all he had found out up to then.

"Now, sir," he said in conclusion, "while you and your men are looking through things here. I'll have a talk to that man on the lift. It's fingermarks you must get hold of, if you can, but I doubt if you'll find any. That man with the bag wore suede gloves, and the precious doctor here, rubber ones." He nodded hopefully. "Still, these kind of gentry often make mistakes, and it's just possible one has been made here."

Leaving Mr. Grant to his investigations, he proceeded quickly down to the main entrance of the building, and was just in time to catch the lift-man passing over his duties to another attendant, and going off for his dinner.

"Here!" said Larose sharply. "I want a word with you, and it's very important. It'll mean a couple of pounds to you, perhaps, if what you can tell me is any good. Where can we go for a little chat?"

The man led the way to a service room in the basement, and Larose came quickly to the point.

Larose rapped out sharply—"Now it's about Dr. Smith and his man Jasper that I want to know. How long has the doctor been practising here?"

The man hesitated. "I couldn't say off-hand, sir, but I should think about a year and a half."

"No; three or four times a week on an average, although some weeks he comes every day."

"No, not always. Sometimes he comes when I'm up in the lift, and sometimes he comes in by the other entrance in Fore street."

"And I understand that his man always gets here before he does?" went on Larose.

"Always," replied the lift-man. He corrected himself. "Except today, and this morning——"

"Never mind about this morning," snapped Larose. "I know all about that. Now, do you always see the doctor go away after he's finished his patients?"

"No, not many. He charges too much, and he's a bit too off-hand with everyone. He never seems to mind whether he pleases or not."

It was now the man's turn to consider. "W—e—ll, you see, sir, I really don't know what patients do go up to him, for his rooms, being on the first floor, a lot of them would use the stairs. Still"—the man appeared to think hard—"still, I should say from the patients I've happened to see going into and coming out of his rooms, that they are mostly youngish men." He nodded. "Yes. I've seen very few old people, now I come to think of it."

Larose eyed him very sternly. "Now one very important question, and you, please, think carefully before you answer it." He punctuated every word with his finger. "You say you've known this doctor and his man for about a year and a half, and you've seen them come and go all that time!" He spoke very slowly. "Well, have you ever seen them either arrive or leave—together?"

The man shook his head. "No. Mr. Jasper always comes before the doctor, and always goes after him." He smiled. "You see, he has to. He gets the rooms ready in the mornings and tidies up in the afternoons."

Larose continued to speak very slowly. "Then never once in all these eighteen or so months," he asked, "has it ever happened that you have seen both Dr. Smith and this man, Jasper, at one and the same time?" He rapped out his words like a bullet from a gun. "You have never seen them—both together?"

The lift-man looked very frightened and his eyes opened wide in consternation as he realised for the first time the drift of Larose's question.

"We—ll, no," he stammered, "now I come to think of it, I don't believe I have ever seen them both at the same time." Then his face brightened on the instant, and he lost his frightened look. "Oh! but this morning I saw Mr. Jasper coming in when the doctor was in his rooms. So——"

"Never mind about this morning, I tell you," interrupted Larose brusquely. "That wasn't Dr. Smith who was up in his rooms. It was someone else, wearing the doctor's wig and beard."

"Yes, yes, of course," said Larose testily, "and you ought to have spotted it months ago." He waved the matter aside. "And now another question, and think again before you answer. How did this Jasper come into the building this morning? Did he walk quickly up the steps?"

"No, I stepped out of the lift to speak to him. I was having a little sit-down when I saw him come in."

"'Hullo!' I said. 'You'll catch it. The governor's been up there half an hour already,' and he stopped dead. 'What do you mean?' he asked. 'He's been here a long time,' I said. 'He's had one patient, too, a woman,' and then I showed him the shilling she'd given me, because she was so pleased. Then I though he looked very ill, for he went awfully white. 'Oh! and I've forgotten his paper,' he said. 'I'll be back in two minutes,' and he rushed out and I haven't seen him again."

"And you won't see him again," snapped Larose, "for he was the doctor and the doctor was him. He saw the game was up and he cut while he could. He's a crook, I tell you."

"But how could I see Mr. Jasper come some mornings," asked the man with a catch in his breath, "and then half an hour later the doctor come too?"

Larose looked scornful. "Couldn't the man go up and put on the doctor's beard and wig," he asked, "then sneak out through Fore street and then make his way round and come in through the main entrance?" He clicked his fingers together. "You booby, he's been making fool's of everyone all along." He spoke very sternly. "Now, look here my friend, this is police business, and for the sake of the building you must hold your tongue. Not a word to anyone. Do you understand?"

Larose then took out the page cut from the 'Sphere' and asked him if he could recognise anyone in it as being at all like Jasper, but to his disappointment the man, after a hard stare, shook his head and was unable to point to anyone.

"Now, just one last question," said Larose. "Do you remember if this fellow, Jasper, or Dr. Smith did not come to these buildings upon any days of the week before last."

"I never saw either of them upon any single day of that week," replied the man most emphatically. "I am quite positive about it, because some of the patients were most unpleasant when the doctor was not here." He smiled a sickly smile. "The ladies seemed to blame me for it," and Larose was quite heartened by his confident reiteration of his statement.

"So I am right," ran his triumphant thoughts. "This Danker, the old tailor, J. Reynolds and Dr. Smith are one and the same man!" His face clouded. "But oh, to link them up with Mitter seems quite impossible!"

He returned upstairs, to find the quiet and uncommunicative Mr. Grant flushed and excited, for probably one of the very few times in his life.

"This is the crowd we're after," he nodded to Larose, as the latter entered the room, "and there are enough problems here to keep us busy for a long time. These four letters are in cipher." He held up a sheet from the 'Sphere.' "Here is a photo of the stranded Mary Belle, and here"—he smiled a dry, grim smile, and pointed to the open page of a small memorandum book upon this desk—"is my private telephone number at my house, although how they got hold of it heaven only knows, for it's not listed in any directory."

"But are there any finger-prints?" asked Larose eagerly. "We might get Mitter that way, if Mitter ever came here."

"No, there are none, except those that are almost certain to turn out to be yours," replied Mr. Grant disappointedly. "Not a single one anywhere where you would expect to find them, and even these rubber gloves here are dusted inside so heavily with talc powder that we shall get no prints from them."

There was a long consultation that night in Whitehall, between Larose, Mr. Grant, Sir Herbert Carnaby, Colonel Bevan and several other heads of the Intelligence Service.

"And they must have great resources and be very finely organised," said Mr. Grant. "We haven't been able to decode those letters yet, but a man who had been staying at Burnham-on-Crouch, since January last, cleared out on his motor cycle just before two this afternoon, leaving all his belongings intact behind him, and, one of the best oxy-welders working on the destroyers in Chatham left his job hurriedly about the same time and we can get no traces of him. Also, there are three absentees from the torpedo sheds in Portsmouth tonight."

He nodded significantly. "Warnings must have been sent out instantly, in all directions, but through what channels there seems no possibility of determining. I tell you, that man at Burnham-on-Crouch cleared out without apparently, a minute's hesitation, and yet no telegrams of any description reached the post office there between one and two, and the only trunk call from London during that time was from a private hospital in Marylebone to the vicar of Burnham about the progress of his daughter who has just undergone an operation." He shook his head. "It is most puzzling!"

"And about those four letters in cipher," said Larose, tentatively. "I've been thinking that, perhaps those leader pages of the 'Times' might perhaps give you the key, the cipher being changed every day."

Mr. Grant smiled. "We have had experts working in that direction ever since I brought the pages here." He looked very grim. "That gentleman who disappeared with such celerity from Burnham-on-Crouch had the 'Times' delivered to him every morning, and the post mistress in the adjacent little village of Southminster remembers stamping a letter, only a few days ago, addressed to a Dr. Smith of Finsbury Pavement." He sighed. "These men are very thorough."

A long silence followed and then Sir Herbert Carnaby remarked in business like tones. "Then, as I take it, the position is this. We have absolutely nothing personally against this Herr Mitter, of Dunwich Hall, for no one recognises him in any of the four personalities Mr. Larose has so cleverly exposed. Still, we know that in any case, it could not possibly have been him in Moon Buildings, because when that pseudo Dr. Smith was attending patients in there, Mitter's butler testified that his master was at home and, added to that, Mrs. Larose had a conversation with Mitter over the phone, almost at the same time." He looked round at the others assembled there and asked:—"Well, with regard to Mitter, what are we going to do?"

"I'll go and see him," snapped Larose. "I'd stake my life he was in this business, somehow, and although he's got away with it, his confidence must be badly shaken now. He must realise that we only just missed a grand slam and it will be a devil of of a worry to him, as he wonders who stacked the cards. Yes, I'll go and see him, and that butler of his, too. Somehow, I'm not satisfied there." He nodded. "And remember, he's got another bit of business on. Don't forget that man who came knocking upon the consulting room door in such a hurry." He looked round questioningly at the others. "Who were those men who went off from some railway station this morning, and what are they up to?" Then receiving no answer from anyone, he smiled and nodded again. "Well, anyhow, I've got a few ideas."

"That's good," smiled back Mr. Grant, "for in all my life, I've never as yet met anyone whose ideas turned out so valuable."

CHAPTER X
THE ADVENTURES OF MARGARET ADVENT

AS Margaret Advent had said, Lieutenant Selby Fortescue was certainly a nice natured boy, and when, just outside the village in the dusk of that Friday evening, he picked her up in his car, he would have been distressed beyond measure had he known exactly what was passing in her mind.

He had been struck with her appearance each time he had called at Dunwich Hall, and had thought her as pretty a girl as he had seen in all his life, and like most young fellows of his age, being always ready for an adventure with one of the other sex, and getting speech with her alone, that day when Herr Mitter was away from home, on the spur of the moment he had suggested they should have an outing together. He just meant to take her to some place of entertainment, give her a good time, and perhaps have a little love-making with her on the way back.

But as for any serious intentions on his part, he would have been aghast at the very idea; indeed, after he had asked her to come, he had felt very ashamed that he was intending to be friendly with the maid-servant of a man at whose house he was an honored and welcome guest.

All his own family moved in good social circles. His late father had been General Sir Newman Fortescue, K.C.M.G., his mother was the grand-daughter of an earl, and his uncle was Sir Blenheim Fortescue, of a baronetcy that went back for more than three hundred years.

Margaret herself was quite aware or his aristocratic forebears, for she had looked him up in Debrett, but, in her great self-confidence she was not by any means thereby deterred from her intention, if she really came to be fond of him, to put their relations ultimately upon a matrimonial footing.

After all, she told herself, if it were only known, she might be perhaps quite as well-born as he was. Her parents, indeed, might be among the very highest in the land, and if, as probably, she had not been born in matrimony, yet it was not her fault and in no wise detracted from her breeding.

She had looked at herself in the mirror just before she had set out to meet him and had nodded with approval at her appearance in the attire that had cost her several months' wages.

She was wearing a well-tailored coat and skirt, a closely-fitting hat that matched her costume, and a white crepe-de-chine blouse. Her shoes had been purchased at one of the best shops in Ipswich.

Young Fortescue elevated his eyebrows ever so slightly as, with a bright nod, she stepped into his car. He knew a smartly dressed girl when he saw one, and the night was still good enough for him to be able to take in the girl's appearance.

"Now where are we going?" asked Margaret, when she had settled herself down comfortably and the car was gathering speed.

It was the question Fortescue had been rather dreading, for although he had set off at a good pace to gain the main road, he had no idea as to where he was intending to take her. He wished he had not mentioned pictures at all, for he certainly could not take her to any in either Ipswich or Colchester. He might meet some of his brother officers in both of those towns, and besides, so many of the county people around were on visiting terms with the master of Dunwich Hall, that it might so easily happen he would he seen in the company of the girl they would at once recognise as Herr Mitter's parlormaid.

"We—ll," he said hesitatingly, "there are no decent pictures on just now anywhere near here, so what about a nice little dinner somewhere, say at the Angel at Bury-St. Edmunds?"

"Oh, yes," said Margaret at once, "a dinner somewhere. I feel quite hungry already." She considered for a few moments and then asked. "But this car's a pretty fast one, isn't it?"

"Well, let's get right away," said Margaret. "The people are so gossipy about here, and you won't want us to be seen by anyone who will recognise me. So, why not go straight up to town?"

"That's a good idea!" exclaimed Fortescue with great relief, and yet wincing a little that she had voiced his thoughts with such accuracy. Then he added quickly. "But it'll make you rather late getting home."

"Oh! That doesn't matter," said Margaret. "In fact, any time will do for me. I've got the latch-key here."

Then a long silence followed as the car sped swiftly along, with Margaret feeling supremely happy. The speed exhilarated her, the purring rhythm of the engine was like some soft and beautiful melody, and she was thrilled that at last she was partaking in one of those adventures which hitherto she had all along denied herself.

Young Fortescue was happy, too. He could not see his companion, as there was no light on inside the car, and besides, at the speed they were travelling, he dared not take his eyes off the road; but mindful of how pretty Margaret was, it delighted him to feel the warmth of her body as it occasionally touched his. He could smell, too, some delicious perfume that he was sure must be, in part innate to the queenly little head so close to his. His pulses quickened at the thought of the bit of love-making he might, perhaps, have on the way back.

They slowed down passing through Saxmundham, and then, outside the town, he switched on the light inside, so that at last he might have a good look at her.

"My word!" he exclaimed, when for a few seconds he had feasted his eyes upon her piquante face, "but you do look nice tonight. Fancy your"—but he hesitated, and then stopped speaking, feeling rather embarrassed at what he had been intending to say.

"——being a parlormaid!" she finished gaily for him. Then after a few moments she went on smilingly. "But for all you know of me, I may be a princess in disguise."

"Gad!" he exclaimed fervently, "and you look like one. Honestly, I've never met a prettier girl before."

She laughed softly. "No compliments, please, for you don't know me well enough yet. Switch off the light, too, if you don't mind and then you can concentrate upon your driving. Didn't I tell you I was hungry and wanted something to eat? Besides, the darkness is so restful."

He obeyed her without a word, and then another long silence followed, until they were running through Ipswich and passing 'The White Horse' Hotel.

"Oh! that's where dear old Mr. Pickwick stayed!" she exclaimed with animation. "Now, do you realise that a whole hundred years have gone since 'Pickwick Papers' was published?"

"No, has it really?" he asked, genuinely surprised. "I had no idea the book was as old as that."

"Yes, and I think that, more than anything, makes Essex such an interesting county for everyone. There's an atmosphere of Dickens all along this road."

"Oh! yes, and I've read quite a lot. My first situation"—young Fortescue winced for the second time—"when I was only fifteen, was with an old Cambridge Don. He had a glorious library, and I read so many of the old classics that no one seems to read today. I got a real education there, as good as any money could buy, for my employer was interested in me, and I sort of studied under him."

"Were you there long?" asked Fortescue, rather astonished at the line the conversation was taking.

"Four years," was the reply, "and then when he died I went to Lady Headle. Everything was quite different there, and it was all newspapers and magazines. She entertained a great deal, but had very few serious people. I stayed with her for two years."

"And I suppose you had a rather rough time there?" suggested Fortescue, frowning, he did not know why.

"But I expect you had plenty of——" then Fortescue hesitated and stopped again.

"Followers! you mean," laughed the girl. She seemed very amused. "I might have had, but I wasn't enough interested in anyone. A member of the House of Lords wanted to take me and train me as his secretary, and the lessee of a theatre offered to get me on to the stage."

It was Margaret who hesitated now. "We—ll, some girls, they say, have a sort of instinct that protects them, and I must be one of them. The peer was a dear old gentleman, but it was me he wanted, and not any secretary at all. Then the theatrical man—well, the salary he offered was much too much and, besides, I was afraid of him. He was very handsome, but he had got a wife, although he was separated from her."

They chatted animatedly all the way to town, and young Fortescue became more and more astonished at the girl's knowledge of things in general. Many times she could have taken him out of his depth in the subjects they discussed, and she was far better informed, he realised, than the ordinary run of girls in his own class. With every mile they travelled he became the more interested in her, but a somewhat chilling idea began now to take possession of him that, perhaps, after all, that bit of love-making he was expecting later, was not quite so sure a happening as he had once thought.

They reached town soon after seven, and driving the car into a garage off Oxford street, he had another shock when he got a full view of her under the big arc lights there.

"But she looks a perfect little lady," he told himself, "and I can take her anywhere." So a few minutes later, instead of the quiet little restaurant in Soho at which he had been intending they should dine, they were walking through the magnificent foyer of the Apollo, one of the most expensive and fashionable places in town.

"And I don't care who sees us," he muttered. "I shall be the envy of every man here."

He chose a table far enough from the orchestra that they could converse in comfort and when they were seated and he had dispatched their particular waiter to fetch the wine one, he handed her the menu.

"That means caviare with egg," he explained, pointing to 'caviare aux oeufs.' "Will you try some?"

She nodded with what he thought was an amused smile, and then when their waiter, an obvious foreigner, returned, she requested the latter in perfect French, to adjust the screen behind her so that she could not feel a draught.

Fortescue reddened in discomfiture, and then when the waiter had gone off, she said laughing, "Forgive that little bit of show-off, but I speak French quite well. I learnt the grammatical part with that old Don, and later was able to perfect my accent with two winters in the South of France. Lady Headle had a villa in Nice and always took me everywhere with her."

"But, by Jove, you're a funny girl to be in anyone's service!" exclaimed Fortescue. "I don't understand it."

"Oh! I shan't be always a maid," she retorted with a smile, "for I'm very ambitious. I'm writing a story."

The big salon was filling rapidly, and she took in appreciatively the beautiful dresses of the women. "Never mind," she told herself. "I'm quite all right as I am, and he can't be ashamed of me."

And certainly she was correct there, for Fortescue was feeling very proud of his pretty companion. Hardly a person passed that did not give Margaret a second look, and the glances of the men near them, he noticed, were many times turned in her direction.

Presently he said, "But tell me, Margaret, how do you come to be where you are?" He frowned, as if very puzzled. "Is there some mystery about you?"

"Yes," she nodded, "there is a mystery"—she sighed—"and one perhaps, that will never be cleared up."

She regarded him very solemnly. "I have no people," she replied, "and I don't know who I am." She looked him straight in the face. "I am a foundling, Mr. Fortescue."

"Yes," she went on, "on Advent Sunday, 22 years ago, someone left me in a basket on the door step of the Foundling Hospital. That is why I am called Advent. The Christian name, Margaret, was written upon a piece of paper pinned to my baby clothes."

"How could I?" she asked. "Where could I begin?" She held out her hands towards him and her eyes sparkled with fun. "What do you think of these, Mr. Fortescue? Do they come from common people?"

With a puzzled smile, he regarded them critically. They were small and dainty, beautifully shaped, with fine tapering fingers, hands that an artist would have loved to paint, or a sculptor to set in marble.

"Hardly!" was his verdict. He lowered his voice impressively, and there was a depth of fervency in his tones. "They are the most beautiful hands I have ever seen."

She bowed smilingly in appreciation of the compliment. "And so do you wonder that I set a value upon myself, that I didn't go as secretary to that old lord or accept the offer that theatrical man made me?" She nodded. "One day I may perhaps come to know who my parents are, and then I don't want to disgrace them, however wrongly they have served me."

Fortescue heaved a big sigh. The bit of love-making, he thought, was receding farther and farther into the background!

They lingered over their meal until nearly 10 o'clock, and then Margaret suggested that they had better think of leaving.

"As it is, I shan't get home until nearly 1 o'clock," she said, "and that's late for a would-be respectable young woman."

There were long, deep silences between them during the drive back when both were busy with their own thoughts.

Young Fortescue's admiration was now mingled with a great pity and an intense longing to protect her, while Margaret was telling herself what a really nice boy he was and hoping that he was not disappointed in her.

Then the girl remembered all at once the real reason why she was supposed to have spent the evening with him, and what Mitter had asked her to find out.

"Because it's in my blood," he replied. "My father and his father before him were soldiers, and we've had soldiers in our family for many generations."

"But I think if I had been a man," she went on, "I should have chosen to go into the air service."

"I wanted to," he sighed, "but I'm the only son of my mother and she dissuaded me." Then his next words, lightly spoken, were to make all the difference to Margaret's life. "Yes, it is the air service that is going to save this little island of ours, for it will be only our aeroplanes that will stand between us and being conquered by some other country." He saw the road in front was clear and flashed a quick look down upon her. "Do you know my dear, if it weren't for those wonderful new planes we've got, everyone is sure a certain country would be making an attack upon us within the next few months. This particular country has only got to find out the secret of them and then—bang—and men, women and children over here will all be gasping out their lives in agony when the liquid fire and poison bombs are dropped."

"Liquid fire and poison bombs!" gasped Margaret. "They would never be so cruel!"

Fortescue laughed. "Oh! don't you make any mistake there. They'll stop at nothing when the next war comes, and if we only knew it, in a certain country they are straining every nerve now to find out where and of what those invisible aeroplanes are made." He smiled in amusement at her astonishment. "Over across the North Sea they are not all harmless and kind-hearted gentlemen like our esteemed friend, Herr Mitter."

But Margaret made no comment. She was too startled to speak. She felt all suddenly as if a knife had been plunged into her heart and she went icy cold and held her breath. Not all kind-hearted and harmless like Herr Mitter! Poison bombs would be dropped in England. Some foreign country was straining every nerve to find out where the new aeroplanes were being made! What did it all mean?

It was as if the door of some room, which, day after day she had been passing with unconcern, had suddenly swung open and disclosed to her a scene of ghastly horror. A mother with her face distorted in agony, clutching to her baby who was in the throes of suffocation from poison gas! A little child who was groaning because its eyes had been burnt out!

Good God! and she had been helping to bring about this dreadful torture! She had been sent out that very night to act the spy!

Young Fortescue was still speaking—"but of course, as I say, Herr Mitter is a gentleman and would countenance none of these things. Indeed, the general opinion is that he is only living over here to get away from the madmen in his own country." He turned the conversation. "But here, I say, when can you come out with me again?"

Margaret found her voice with an effort. "Whenever you like," she replied, a little faintly. "I can always manage it."

He considered for a few moments. "Well, what about next Thursday? We'll go to a night club I belong to and you shall enjoy yourself. I promise you."

Margaret hesitated. "My dress will be all right," she said, "but I have no jewellery at all."

He laughed merrily. "Your eyes, Margaret, will be finer jewels than anyone's there. No, of course, having no jewellery doesn't matter. You've quite enough to please without that."

They drove on for many miles without further conversation until at length they came to the place where he had waited for her just outside the village, and there the boy slowed down and finally stopped. Then with a sigh he stretched out his hand to open the door, while Margaret was thanking him prettily for the good time he had given her.

"And I've enjoyed it tremendously," he said. "Never had a better evening in all my life."

A short silence followed and he still kept hold of the handle of the door. Then he said suddenly and with a little catch in his voice. "But I say, Margaret, aren't I going to have any reward? Nothing at all?"

She made no pretence she did not understand, but after a hesitating a moment, said, laughing softly. "I suppose I ought to give you something," and she put up her face to his. "Just kiss me once." Then as he attempted to draw her passionately to him, she exclaimed quickly. "No, not an embrace, Mr. Fortescue. P-l-ease, not yet," and so all young Fortescue carried away was the memory of two soft lips that he had been allowed to press ardently, but for a very short time.

"Damn the little witch!" he exclaimed, as he drove at a fierce pace back to Colchester, "but I'd have almost given a year out of my life to have got as many kisses then as I wanted!"

That night neither he nor Margaret slept much. The boy tossed and turned and turned again. One minute he was furious with himself for harboring such longings for 'a parlormaid,' and the next he was considering Margaret as of patrician blood and worthy in every way to be the mate of any man.

"Poor little devil!" he murmured. "I wonder what her future's going to be!" He shut his tired eyes with a vicious snap. "Wouldn't mother gasp if I told her that I was falling in love with someone's parlormaid, and yet—wouldn't she be proud of her if she were only one of our own set."

And Margaret had tender thoughts, too, but they were all forgotten when she had tucked herself in bed and lay wide-eyed, staring into the darkness.

She was simply horrified at the realisation that had come to her so suddenly as to what the true nature of Mitter's work must be. She could see now that for months, and months, and all unknown to her, a store of dangerously inflammable material had been accumulating in her mind. Then one chance word of young Fortescue's had been the spark to send it up in awful flames.

Day by day, Mitter had been trusting her more and more and she had come to know so many of the secrets of Dunwich Hall and its master, secrets, however, that the latter had always made out to her were harmless or of little importance to anyone.

Now, however, she knew differently. His secrets were dreadful ones, and might mean most awful suffering for thousands and thousands of poor helpless creatures, whose only fault was that they were not of Mitter's own country.

And the Government knew something of what Mitter was doing, for they were getting Dempster to watch him! But they did not know half what she knew, for they did not realise the trick that he was playing them. They did not know that he—oh! but there were scores of things they could not know, or they would have stopped him a long time ago.

She tried to think calmly of what she must now do. Of course, she did not intend to tell anyone about him, for he had always been very kind to her, and she had once thought she had been very fond of him. No, she knew she could not betray him!

But then suddenly a feeling of great resentment began to surge through her and she saw things in a very different light. Herr Mitter had certainly been most kind to her, but had it not all been she now asked herself, simply to serve his own ends? In the beginning he had led her on to become fond of him, being sure then that she would never tell anything of what she might learn was going on in Dunwich Hall. But now with her eyes opened, she could so plainly see that after all he had only trusted her just as far as he had been obliged to, and that in many, many ways she had been as intentionally deceived as everybody else.

Well, she would never lift a finger to help him any more! She would never get hold of Dempster's letters again, and she flushed with shame as she thought of what would be young Fortescue's opinion of her if he knew what she had been doing there.

Her thoughts ran on. Of course, she must leave Dunwich Hall as soon as possible. She would tell Mitter she wanted to better herself and had decided to go to London to get a proper training in some school, for secretarial work. If he objected, then she would disappear suddenly. Thank heaven, she had saved some money!

But she would not let Mitter know what she was now certain of him. She would appear just the same to him, until she had perfected all her plans, and as for Dempster's letters—well she would say he gave her now no opportunity of getting hold of them.

She fell asleep at last and had a dreadful dream that someone had just saved her from being murdered. She did not know who her rescuer was, but she thought his face was like that of one of Herr Mitter's friends, the pleasant smiling Mr. Larose, who had that beautiful wife with the red hair.

After breakfast when she was busy in the study, Mitter came in and asked her, smilingly, how she had enjoyed herself the previous night. With a great effort, she masked her feelings, and, smiling back, told him where Fortescue had taken her.

"And did you get anything out of him about his airman cousin?" asked Mitter eagerly.

"No, I brought up about aeroplanes," she replied, "but he didn't mention him." Then as she saw Mitter frown, she added, "I couldn't be too pointed in my questions, all at once, but as he's asked me to go to a dance with him on Thursday, I may perhaps find out something then."

"Well, mind you try hard," nodded Mitter. "Find out where that cousin is, for it's most important."

Then followed for Margaret a very eventful fortnight. Fortescue took her out three times, and with each meeting they both fell deeper in the toils. Never for a moment now did he regard her as a parlormaid, and all his thoughts were that one day she would become his wife.

He was delighted when she told him she was intending to leave Dunwich Hall, and one day he made a special visit to town to pick out some training school for her.

"And you can forget then, sweetheart," he said, the last night when he was bringing her home in the car, "that you have ever been in anyone's service. With what you know now, your training should be a very short one, and then, with your appearance, you'll be sure to get a good position at once." He laughed happily. "But you won't be keeping it long, for I'm quite well off and we can be married next year."

"But I'm not aware, dear," she laughed back, "that I've agreed to marry you yet." She became serious. "What will your people say when you tell them you are marrying a nameless girl?"

"I shan't tell them," he said emphatically. "No one shall ever know. We'll invent some mythical parents who died in Australia and we'll have it all cut and dried. You must get a position, too, with some newspaper, and then it will sound so much better when I introduce you to my people as a journalist. That's quite respectable and may mean anything. I can say you're a literary woman."

She considered for a few moments. "But now I think seriously of you, Selby"—they had exchanged kisses without reserve—"It doesn't seem quite fair to me, for in one way you are certainly giving so much and I so little."

"Nonsense!" he exclaimed sharply. "You are giving me the most wonderful present in the world." His voice dropped into tender tones. "You are giving me yourself, sweetheart. We are man and woman together, and there is no difference between us now."

The opiate dreams of Youth! Slumber so deep that there would he no waking till the passion hours had passed, and then, maybe, the memory of their dreamings would hallow all their lives—until Life ended!

But the terrible moment came when Margaret had to tell Mitter that she intended to leave him. She knew he was not pleased with her, for she had averred, insistently, that she could get no information out of Fortescue, and, added to that, she had made out she could no longer get hold of Dempster's letters, for the latter, she had said, had taken to carrying them about with him, in his pocket, until they were actually given into the hands of the postman.

It was one night, too, when Mitter appeared to be dreadfully worried, although she had not realised it until she had started to speak.

She had come into his study when all the rest of the household were asleep, and had found him lying back in an armchair and gazing with deep thought into the dying embers of a fire that he had been too preoccupied to notice had almost gone out. When he turned to listen to her she saw that he was frowning heavily and that his face seemed deeply lined with care.

For a few moments he regarded her as if he was not taking in the import of what she was saying, and she had to repeat what she had come to tell him.

"So you want to leave, eh?" he ejaculated incredulously, and then he rapped out sharply, "What's your reason?"

"I just told you," she said. "I want to better myself. I don't want to remain in service any longer."

He shook his head frowningly. "No, give me the real reason," he said. "That's not the real one." He spoke very sternly. "Is it Lieutenant Fortescue who has advised you to do this?"

She hesitated. "He didn't advise me, but when I told him what I was going to do, he certainly agreed it was the best thing. He's found a training school where I can go to learn the work of a secretary."

Mitter smiled a dry, grim smile. "Very obliging of him, I am sure." He eyed the girl very intently. "Are you in love with that boy, Margaret?"

She nodded again, but this time without replying, and he went on sharply. "Has he asked you anything about me?"

"Not one single thing," she replied instantly. "He has a very high opinion or you." She raised her voice slightly and spoke with some emotion. "Oh! don't you understand, Herr Mitter, why I must leave? An officer in the army cannot marry a parlormaid, and I want to be something better than that when I become his wife."

"But you have been such a help to me," he began, speaking very slowly, "you have——"

"I know what you're thinking," she broke in quickly, "but you need not have the slightest worry there. I shall never tell anything of your affairs to anyone, not even to Mr. Fortescue, if I become his wife. It will be as if I had never helped you in any way."

"And I think I can be sure of that," he nodded, after a moment of reflection. Then he asked abruptly. "But when do you want to leave?"

He appeared to consider. "Well, give a little time, a fortnight or so, or perhaps a little longer." He spoke very sadly. "I shall be sorry to lose you, Margaret." He shook his head. "But run away now. I've a lot to think about. Good-night."

Then when she had gone and the door was closed behind her, he drew in a sharp breath. "Yes, damnation, a lot to think about, and now you, young woman, have given me even more still!" He nodded to himself. "But with the best of intentions, if she leaves, she will be dangerous! A woman is too emotional to trust when she's in the close intimacy of married life. One day that boy will ask some chance question about us here, and then—out in a rush will comes all she knows."

He seemed to hesitate in his thoughts. "N-o-w, if she were a man, I could deal with her, for extreme measures would be entirely justifiable here, but a woman and a girl like Margaret—well, well, I must think what I must do." He shook his head vexatiously. "But she shall not go to London. She shall be got out of the country, somehow."

He thought on. "But what did really happen this morning, and how did they come to learn of Moon Buildings? It is a terrible blow, for it means that there is a traitor somewhere! Not that they can lay hands on anyone now, for the warnings went out in time! And not, even if they make out these cyphers, will they learn anything further, for they will be at a dead end there, too, as I have confided in no one man to the extent that it is in his power to betray us all!"

He almost held his breath. "But the dreadful thought is I do not know who this traitor is, and when I entrust to him more work, he may betray us again! So, the question is, dare I go on with this other matter? Yes, yes, I am safe there, for the traitor cannot be either Fletcher or Dukes. They do not know of the existence of Moon Buildings."

He thought on for a long while, and then his face brightened a little. "But perhaps after all it had nothing to do with the Intelligence Department, and I am worrying myself without reason. It may have been just some chance thief who got into the rooms, and then bluffed it out when that woman patient somehow surprised him." He sighed doubtfully. "At any rate, I shall be sure to learn soon."

And he did learn very soon, for in the middle of that same night he was awakened from a fitful sleep by a gentle tapping upon the window of his room, and jumping out of bed, he lifted the window very softly.

"There was a long deliberation tonight at Room 13," came the low whisper of a man who was crouching down outside, "and Gilbert Larose was among those who were there."

"Whew!" whistled Mitter, and his heart almost stopped beating, "Gilbert Larose! Are you sure?"

"Yes, and he was still there when I left, just after midnight, but I think his car passed me on the Ipswich road, as I was coming here. He was doing seventy."

"Gilbert Larose!" ejaculated Mitter, as if he could hardly believe it. Then he gritted his teeth together. "Yes, I know he's been away from Carmel Abbey for nearly a fortnight, and yesterday we were rung up from there with some excuse, that I see now, was to find out where I was." His voice calmed down to even tones. "But have you any more news?"

"No," came the reply, "but I thought that would give you something to think about, anyhow," and the speaker slipped away into the darkness.

Mitter drew down the window again, and returned to his bed. But there was no more sleep for him that night.

CHAPTER XI
DEADLY NIGHTSHADE

JUST before noon upon that day, but one, following the startling discoveries in Moon Buildings, Larose drove into the grounds of Dunwich Hall, with the intention of having a talk with its master, or if the latter were away from home, of getting a word in private with the butler.

He was thinking that at any rate he would achieve something by his visit, for if he saw Mitter himself he was hoping he would be able to determine from Mitter's demeanor whether or not the latter were in some state of mental anxiety, as undoubtedly he should be, if he were concerned in the staggering blow that had been dealt to the pseudo Dr. Smith, the practitioner in diseases of the skin.

Larose himself was still worried there, for although from the testimony of the butler he realised that by no possibility could Mitter have been the man on Foulness, or the man with the bag, or Dr. Smith, yet he could not altogether deny the instinct that continued to hammer so insistently upon his mind that Mitter was much more deeply involved in the whole business than, upon the surface, appeared.

The day was fine, but a storm threatening, he parked his car in the drive, round a side of the house where it would be out of the way of the strong wind that was blowing in from the sea.

"Is Herr Mitter at home?" he asked, regarding the man more interestedly than he had ever done before.

"Yes, sir," was the reply, "but I think he's in the rose-garden. I'll go and fetch him at once."

"No, no, I'll go and find him myself," said Larose, and then he lowered his voice to a whisper and added sharply, "See here, John Dempster, I'm from the Intelligence Department and I want a word with you. When and where can I meet you?"

The butler's mouth opened and he looked very disconcerted. "From the Intelligence people, sir?" he asked hoarsely, and with his voice shaking.

"Yes, and I want to talk to you about those letters you are sending us," said Larose. "When can you arrange it? Tell me, quick."

The man gave a hurried glance over his shoulder. "Hush! hush!" he whispered, jerking his head in the direction of an opened door in the lounge, "there's the parlormaid in there." Then he stepped out into the drive and spoke loudly. "Just across that lawn, sir, along by that big wall. He was there not five minutes ago." He dropped his voice to a whisper. "About a mile from here there's a plantation on the Westleton Road on the left. Drive your car round it and you'll be out of sight. I'll be there soon after two. I can slip away then, without being wanted. It'll be my time off."

Larose nodded, and, turning round, proceeded to walk across the lawn to where he knew the rose-garden was. Passing round the corner, he saw Mitter standing just by a massive oak door that was set in the great high wall of the ruined Priory chapel. Matter's face was turned upwards, and he was seemingly absorbed in contemplation of a large broken arch upon the top of the wall. Then suddenly he bent down, and placing his ear against the wall, appeared to be listening intently.

"Good morning, mein Herr!" called out Larose gaily. "You're not thinking of climbing up here, are you?"

Mitter turned sharply at hearing the voice and then apparently taking in who it was, his face broke instantly into a warm and friendly smile.

"Good morning, Mr. Larose," he exclaimed heartily, "I am delighted to see you," and then he laughed as if, Larose thought, he had not a care in all the world. "No, my friend," he went on, "I am not thinking of climbing up, and, indeed, I should be very sorry to attempt it." He pointed up to the ruined arch. "That arch and this wall appear to me to be both getting very dangerous, and any time when there's a wind blowing, such as today, I anticipate a catastrophe." He nodded. "There'll be a tremendous crash one day, and all this mighty masonry will come toppling down."

"Yes, but the mortar's crumbling badly now. It's stood for eight hundred years, and that's a long time, you know."

Larose regarded him with great disappointment. There were no signs of any worry about him, and not only that, but the shape of his face seemed more different than ever from that of the man they had seen looking up towards them in the street on Finsbury Pavement.

"I'm sorry," went on Mitter, shaking his head, "that I cannot accept your kind invitation Mrs. Larose spoke to me about, but I'm getting over a bad cold and I've got a touch of sciatica, too. Sciatica always attacks me when I'm a bit out of sorts."

They moved off down the garden, and Mitter pointed out with pride a bed of beautiful chrysanthemums. The gardener appeared as they were talking, and touched his tattered cap respectfully to Larose.

"Good morning, Sullivan!" exclaimed the latter, smiling at the dirty and disreputable looking figure that had shuffled up. "Those cuttings you took for me came up well."

"Sure, so-or!" said the man in a rich Irish brogue, "I thought they would." He waved his arm round. "There's too much salt here to get the best out of things. I always say——"

"Cut Mr. Larose a nice bunch or these blooms," broke in Mitter sharply, "and bring them up to the house." He turned to Larose. "You'll stop to lunch, of course, my friend. No, no, I won't take any denial," and then, when they moved off, he went on with a frown. "I have to put up with a lot from that man, for he drinks heavily and will never make himself look respectable. Still, he's a splendid gardener, and can be trusted, absolutely, when he's sober."

"But I say. I really oughtn't to stay to lunch," frowned Larose. "I've got to go into Ipswich for some things for the wife and the shopping will take me a good time."

"Well you're not going until you've had lunch," said Mitter firmly. "I feel lonely today, and want someone to talk to. Besides"—and he laughed merrily—"everybody knows you drive like the very devil, so you can easily pick up the lost time upon the road."

A few minutes later Larose was in a way of being highly amused with his own thoughts.

He was sitting at lunch with a man whom he knew to be a notorious spy and whom he hoped to prove to be murderer, as well.

The man had charming manners, was a perfect host and, apparently, there was nothing he had too good to offer to his guest.

"Now, a slice of turbot," said Mitter, "some cold pheasant and a bit of ripe Stilton are the best I can give you for a scratch meal." He smiled and lowered his voice mysteriously. "But we will make up for it in the wine, for I've had a bottle of '82 Lafitte brought up." He frowned. "I'm afraid, however, you won't be drinking it quite at its very best, for by rights it ought to have been out of the cellar a good couple of hours ago. As you see, I've had to put it before the fire, with the glasses as well, although, of course, I don't approve of that quick way of bringing it to its proper temperature."

He turned to Margaret, who was waiting upon them, as Dempster had been told off, just before the meal, to make some adjustment to the brakes of one of the cars. "It's all right," he said to her. "I'll serve the wine myself, when it's ready."

Then when the girl had left the room to bring in the second course, he remarked in a whisper to Larose. "She's pretty that parlormaid of mine, isn't she?"

Then when Margaret returned to place the cold pheasant upon the table, Mitter jumped nimbly to his feet and kneeling down by the fireplace, proceeded, very carefully, to uncork the bottle of wine. He filled the glasses where they were and rising with them in his hands, with a care almost amounting to reverence, placed one before Larose.

"And I do hope you'll like it," he said, anxiously, as if it were a most serious matter, "for it's a wine I'm very proud of and I've only got a few bottles left. It has a delicious, but rather peculiar flavor, from the soil where the grapes are grown."

Larose sipped it with great appreciation and had just started upon a portion of pheasant when the tinkle of the telephone bell sounded, and with a frown and gesture of apology, Mitter rose to his feet.

"It's a trunk call from my broker that I've been expecting," he explained. "I shan't be a minute."

Then directly he had left the room, to the astonishment of Larose, the parlormaid glided up and proceeded to whisk his half-emptied glass away.

"Excuse me, sir," she said apologetically, "but I see there's some cork in it," and carrying it off with her, Larose saw her empty it into a dish upon the sideboard. Then she brought it back and replaced it by his side.

"But you shouldn't have poured the wine away," said Larose, reprovingly. "Herr Mitter thinks it much too precious to waste a single drop." Then seeing the girl looked rather scared, he added smilingly. "Well, he needn't know about it. We'll consider it as drunk."

Mitter bustled back into the room and started to resume his meal, enjoining Margaret refill Larose's glass, which he had at once noticed was empty.

The lunch was quite an animated one, and they discussed literature, art and flowers. Then Larose brought up the subject of invisible aeroplanes, hoping to observe some unusual interest in the expression upon the face of his host.

And he was certainly not disappointed there, for Mitter at once became most enthusiastic.

"A wonderful invention," he exclaimed, "for it is peace we want! All the world is sick of war and anything that tends to make nations chary of starting trouble, is the best thing for everyone."

Larose felt a sudden chill run down his spine, and with difficulty he suppressed a shudder. With what deadly purpose must Mitter be endowed, he thought, that, with such deceit and guilt upon his mind he could yet talk in so friendly a manner!

Soon after lunch Larose said he must be going, and declining to allow his host to come beyond the front door because it had started to spit with rain, he made his way round the drive to where he had left his car.

"Yes," he nodded, "he's of the most dangerous type imaginable, and behind that pleasant, smiling face, lies a savagery and ruthlessness that will stick at nothing."

Jumping quickly into his car to get out of the rain his eyes fell suddenly upon a wrench, on the driving seat, that he at once recognised as belonging to his own kit of tools.

"Hullo! hullo!" he exclaimed wonderingly, "now how the devil did that get here? I'm sure I never took it out."

For a few moments he thought hard and then he shook his head. "No, and I'll swear it wasn't at the back of the seat, either, when I left home. I should have felt it at once." He shook his head again. "But there it must have been, although it seems very funny."

He started the engine and letting in the clutch drove slowly out of the grounds and through the village. Then when he was over the rise and had left the village behind a sudden thought struck him and he drew in a sharp breath.

"Gosh!" he exclaimed in some consternation, "what if someone's been monkeying with the car and forgot to put the wrench back! I'll get out and have a look round," but then seeing the plantation of trees only a little farther on, he thought better of it. "No, I'll do it when I stop," he added, and he drove on until he had turned off the main road and was hidden by the trees from all passers-by.

The butler had not arrived as yet at the rendezvous, and so, in a rather half-hearted way and now inclined to think it was all waste of time. Larose proceeded to look over the car.

For a couple of minutes or so he found nothing wrong, but then, bending down under the car, and giving a good pull and twist to the rod that connected the steering crank to the arms of the stub axle—to his horror the rod came away in his hand! The protecting cap had been taken off, the safety pin removed, then the cap replaced and all the steering of the car had been left dependent upon one slender thread of the screw!

"Good God!" he gasped, and his eyes almost started from his head. "Then Mitter knows!" The full devilry of it came home to him, and he gasped again. "Any second that rod might have dropped off, and what would have happened if I had been going at speed?"

He took out his handkerchief and wiped the perspiration from his forehead. "Yes, Mitter did it," he murmured brokenly, "in those few minutes he left me, just before lunch. I thought when he came back that his eyes were avoiding mine!"

Then, recovering his equanimity, he smiled with resignation as if it were all in the day's work. So he took out his tools and was just proceeding to jack up the car when the butler appeared round the corner of the plantation upon a bicycle.

"Sorry I'm late, sir," panted the man, "but I couldn't get away before without being noticed."

"Quite, sir," replied Dempster. "I came by a bridle path across the fields," and then, glancing down at the car, he asked, "What's the trouble, sir?"

"Have a look," replied Larose grimly, "and tell me exactly what you make of it."

The man bent down, and, lifting the disengaged end of the rod, regarded it very curiously. Then he twisted the cap with his fingers, and after a very scared look at Larose, stood up with the cap in his hand.

"It must have been almost off!" he exclaimed hoarsely. "It could only have been hanging by one thread, and there is no cotter pin there."

"Exactly," nodded Larose, "and so some kind person intended I should have an accident"—he nodded a second time—"and a very terrible one if I had been going at any good pace." He snapped out his next words—"Now, who did it? It was done at your place."

"Sure, man!" snarled Larose. "Why I was averaging forty all the way here and nothing happened!" He calmed down and spoke very quietly. "Now what do you make of it, Dempster?"

But the butler could hazard no opinion. He was dumbfounded in his surprise and consternation.

"If I thought your precious master had any idea why I'd come here today," went on Larose, "then I could understand it at once, for he left me alone in the library a long five minutes before lunch, and he had ample time to do it then." He picked up a wrench. "But come on now, help me to put it right. You must not be away too long."

The steering was quickly put in proper order again, and then, to make things sure, they expeditiously went over all other vital parts of the car. But apparently nothing had been tampered with anywhere else.

"Well," said Larose at last, "we'll have to leave this as a mystery to be solved later on. We can't give any more thought to it now." He looked intently at the butler. "Now, you've been in the army, haven't you? You were a non-commissioned officer once?"

"Then you will realise the importance of the work that has been entrusted to you and how much may depend upon the reports you send to Major Rankin? You have fully taken in that your master is a secret agent for a foreign country, in other words that he is a spy?"

"Yes, sir, and I'm very sorry to know it, for I couldn't wish for a better master. He's very kind to us all."

"Never mind about that," said Larose. "That counts for nothing. The more pleasant and agreeable a spy, the more dangerous he is to the country he is spying upon. Now, tell me of whom the household at the Hall consists. How many of you are there?"

"My wife, sir, she's the cook, myself, the parlormaid who waited upon you at lunch. Jane the housemaid, Sullivan the gardener, and the master himself. Sullivan doesn't really belong to the household, for he lives in that cottage by the Priory wall and does everything on his own. He never comes into the house."

"Oh, no sir. In fact, I attend to him very little myself. Margaret, the parlormaid, does far more for him than I do. You see, I was engaged as a chauffeur mechanic as well as a butler, and I've two cars to attend to, and they occupy a lot of my time. Some days, indeed, I'm hardly in the house at all, being all day at work in the garage."

"And are you positive," said Larose impressively, "that Herr Mitter was not absent from here at any time upon those five days, three weeks ago, about which we have been enquiring so particularly?"

The butler nodded emphatically. "Quite positive, sir. He did not use any of his cars upon those five days, and in fact I don't think he left the house at all. He was hard at work in his studio."

The butler hesitated. "N-o, sir, I'm not quite sure about that. As I say, he was very busy in his studio that week, and when he's painting he sticks hard at it and we see very little of him."

"Then you did not see and speak to him every day during that week?" rapped out Larose very sharply.

The butler hesitated again. "Well, if I didn't actually speak to him, I certainly saw him, but I took some of his meals into the studio, where he always has them when he's busy." He went on quickly. "You see, sir, the master is rather reserved and eccentric at all times, but we have accustomed ourselves to his ways. Some days he's moody and hardly speaks a word to anyone. Then if we even say good morning to him, he may not answer, and we are not a bit surprised. In fact, many days he's queer in the morning, and doesn't seem to be able to brighten up until the evening. Then he answers, and is quite a genial, pleasant man again. Very different, indeed, to when he's got his painting brush in his hand."

"Then you say you didn't take in all his meals to him on those particular days we have been asking you about," remarked Larose thoughtfully.

"No, sir, Margaret waited upon him very much more than I did, but then that's quite in the ordinary way, for she's far more than a parlormaid in the house. She types the master's letters for him, and he is training her to be his secretary." The butler nodded. "Margaret is a very superior young person, sir, and we don't really know who she is. No friends or relations ever come to see her, and she never gets any letters at all. She's very reserved, too, with us all, and talks more to the master than to anyone in the kitchen."

"No, no, sir," interrupted the butler instantly, and quick to follow the other's thoughts, "there's nothing like that about Margaret or the master either. Besides"—and he smiled knowingly—"Margaret has a gentleman friend now."

"Oh! no, sir," replied the butler, looking quite horrified, "she would never take up with anyone like that. She's well educated and speaks French and German." He gave a sly smile. "This gentleman she is going out with is an officer, and a friend of the master. He's Lieutenant Fortescue and he's stationed at Colchester."

"But surely he doesn't come up to the house for her?" asked Larose looking very puzzled.

"No, his car waits for her outside the village and we only happen to know whose it is because the constable here recognised it. It's a light grey one and rather conspicuous."

"A young gentleman, very well connected, sir. His uncle is Sir Newman Fortescue and his cousin, I believe, is Wing-Commander Fortescue, attached, they do say, to those new invisible aeroplanes somewhere."

Larose felt a feeling of great exultation thrill through him. At last he had got hold of something! Mitter's intimate association with this girl, the girl's association with Lieutenant Fortescue, and Fortescue's relationship to the wing-commander of one of the squadrons of the invisible aeroplanes!

"And is Herr Mitter aware that this girl is going out with the lieutenant?" he asked after a moment.

"Oh! I should think so, sir, or he wouldn't be letting her come home so late. She was at some dance the night before last and didn't get home until 4 o'clock in the morning. I heard her come in."

"Not very long, sir, for it's only within the last few weeks that she's been buying new frocks and things." The butler nodded solemnly. "She looks a real princess when she's in evening dress, a very beautiful young woman."

Larose changed the conversation. "Well, tell me," he asked, "does your master eat chocolate at any time?"

"Not when he's at home," replied Dempster, "but I've heard him tell people that he eats it quite a lot when he's away. He's had food-poisoning once, and he never likes to have meals at strange restaurants, if he can avoid it."

A short silence followed, and then Larose asked. "Well, is there nothing more you can tell me?"

"One thing, sir, and I was going to mention it." He lowered his voice to a whisper. "The night before last, someone came to the master's bedroom window in the middle of the night, and about two minutes' conversation took place. I had come down to get some brandy for my wife who wasn't well, and, passing the master's rooms, I heard the window go up. I stopped to listen, and heard low voices, for a very short time. Then the window was pulled down again very quietly."

"Hum! and how has Herr Mitter been lately?" asked Larose when he had apparently digested this piece of information.

"These last two days very irritable, sir. You brightened him up a lot just now, for yesterday and this morning he was very glum."

They talked on for a few minutes, and then Larose said thoughtfully:—"Then, as I understand it, upon all those days about which we particularly want to know, your master has been painting in his studio. He has not been leading his usual life, you have not seen him about the grounds, and he has hardly spoken a word to you!"

"And this Sullivan, this gardener, you say," went on Larose, "never comes into the house, and I understand is sometimes drunk for days and days on end."

Larose considered for a minute. "And what time do you all generally go to bed? I don't mean your master, but you and your wife and the maids?"

"Well, now, you listen to me," said Larose, regarding the butler very intently. "On your master's desk just now, I saw an invitation to the mayoral banquet at Ipswich to-morrow night. Do you know if he's going?"

"Yes, sir. I heard him arranging on the phone to pick up Dr. Stedman, of Wickham Market, and give him a lift. They are both going."

"Good!" said Larose. "Then to-morrow night at exactly half-past ten, you are to let me into the house, so that I can have a look over your master's study and his studio. I want to run my eye over his things there."

The butler looked very frightened. "Oh, but, sir, it'll be very risky. Suppose the master comes home early!"

"Then I'll get out of his bedroom window," replied Larose. "I shall hear him come in. No, no, you can go off to bed directly you've let me into the house. I shan't want any more help from you at all."

But Dempster was most unwilling, and it was only after Larose had spoken very sternly and reminded him of his oath to the Intelligence Department that he reluctantly agreed. It was arranged then that Larose should come in through the kitchen window.

They parted a few minutes later and Larose turned on to the main road. As he drove along he tried to sum up all he had learnt from the butler, but somehow he did not seem to be able to think coherently, and in a few minutes, to his dismay, he began to feel quite out of sorts. The light hurt his eyes, his heart began to palpitate quickly and he felt giddy and altogether very queer.

Arriving at the little town of Halesworth and feeling no better, he drew his car in to the side of the street and switched off the engine.

Then just as he was alighting with unsteady steps from the car, he saw a tall professional-looking man about to turn into the house right in front of him, and at the same moment his eyes fell upon a brass-plate upon the wall. 'Dr. Browning.'

"That's a bit of luck!" he exclaimed dizzily, and before the professional looking man had time to shut the door, he accosted him. "Are you Dr. Browning?" he asked, breathlessly, and upon the man nodding in affirmation, he added. "Can I speak to you for a few minutes, please?"

The doctor led the way into his little surgery and motioned Larose to a chair. "Well what's the trouble?" he asked.

Larose explained what had happened and the doctor at once laid his fingers upon his pulse.

"But I'm beginning to feel better now," said Larose, drawing in a deep breath. "I think it's passing off. My heart's not going so quickly now."

"You've been taking some drug," said the doctor sharply. "The pupils of your eyes are very dilated."

"No," replied Larose, with a shake of his head. "I haven't," and then a rush of thoughts surging through him, and not anxious that the doctor should get the idea that someone had attempted to poison him, he added quickly. "Only a tonic that my medical man has been prescribing for me."

"Well, what's been the matter with you?" asked the doctor, and Larose replied with the name of the first ailment that came into his mind. "Sciatica."

The doctor nodded smilingly. "Yes, and of course he's been giving you belladonna," he said, "and you are either very intolerant to it, or else you've taken too big a dose. When did you take it last?"

With a dreadful pang, Larose thought of the claret he had had at lunch and the way Mitter had juggled with the wine glasses by the fire.

"When you were having your meal!" frowned the doctor. "What a funny time to be taking it!" He nodded again. "Well, that accounts for so long a time having elapsed before you began to feel its ill-effects. You took it on a full stomach."

He laid his fingers again upon Larose's pulse. "Yes, it seems to be passing off now, and you'll probably be right again in a few minutes."

The doctor shook his head. "No, far from that. The symptoms would have been much more pronounced if you had. You took just enough to make you feel bad and obscure your vision a bit." He looked grave. "But you might have had a very bad accident with the attack coming on when you were driving a car."

"And if I had taken double the quantity I did," asked Larose, remembering with great thankfulness the cork in the first glass of wine that he only half drank, "would that have been dangerous?"

The doctor hesitated. "N-o-o," he replied, "it wouldn't have actually poisoned you, but it would certainly have made you feel much worse for much longer. You would not have died."

He gave Larose a stiff dose of sal volatile and making him wait half an hour, at last pronounced him quite all right and fit to resume his journey.

"Whew!" whistled Larose when he had left the little town behind him, "but aren't things clear now? Somehow Mitter has found out that I'm after him, and a good and quick workman, he gets to business at once. That matter of the belladonna gives him away completely and there's not the slightest doubt now it was he who tampered with the car. Then, as I thought, there's not the slightest doubt either that Mitter was mixed up in some way with both Moon Buildings and Foulness Island."

He frowned. "And, although it's not nice to acknowledge, I must nevertheless accept it as an unpleasant fact that when anything goes wrong with his plans his resources are such that he is able to find out at once how they have come to be upset."

His thoughts ran on. "Now about that very good-looking parlormaid of his, and there can be no doubt she and Mitter are on very friendly terms. Dempster's a bit of an innocent, and I should say she's Mitter's mistr——" he smiled, "well, at any rate he's got a hold upon her and they're working together hand and glove. She's a mystery to the other servants and no one knows where she comes from. I shouldn't wonder if she's not a foreigner, too, although she doesn't look one and her English is perfect. Of course Mitter has set her on to that young Fortescue, and I should say the information as to where that glass is being made came, in the first instance, from the boy." He nodded grimly. "At any rate, I'll have a talk with that young man to-morrow and just find out exactly what he's told the girl."

He frowned. "Now, another thing—when did Mitter come to find out that I was mixed up in this, to the extent that he thought it necessary to do me some grievous harm? He cannot possibly have found out that I have been working down at Southend, for the whole time I have been in some sort of disguise and, unless he were actually suspicious and brought in close contact with me, he certainly would not have seen through that disguise. Now I wonder"—his thoughts were very puzzled ones—"I wonder what information that visitor brought to him when he tapped upon his window in the middle of the night. Dempster says they only spoke together for two minutes and that undoubtedly means the news the man did bring was snappy and probably the stating only of one single fact. Now could it have had anything to do with me, for that night was the only time I had gone to Whitehall in my own car and as my proper self, just as I am?"

He switched his thoughts into another direction and frowned again. "Now there's something very curious about Mitter's painting days. He seems to have always been in his studio when, as I have been imagining, he's been somewhere else. He's moody then, too, and speaks to no one, and always at those times it is that girl that is in closest contact with him." He nodded. "Yes, the girl looms very large in the picture then, this girl who is acting as his secretary, who is in his confidence, and of whom, I am sure, he has made another spy!"

He drove on for a long time without, apparently, being able to give shape to his thoughts, and then, suddenly, he started, so much so that he made a wide swerve in the steering of the car, and had to pull the steering wheel round fiercely to get it straight again.

Then the puzzled expression upon his face was all swept away and he threw back his head and burst into a hearty laugh, a loud exultant laugh, as if he were delighted about something, the laugh of a man who was on excellent terms with himself.

"Of course! of course!" he exclaimed, drawing in his breath in big gulps. "I see it all now! Everything's clear at last!" He could hardly contain himself in his excitement. "MITTER HAS GOT SOMEONE WHO DOUBLES FOR HIM, AND THE MAN WHO DOES THE PAINTING IS NOT MITTER AT ALL!"

It was some moments before he could breathe evenly again and then he went on. "Yes, yes, that's it! Mitter away in London, at Southend and on Foulness, and the painter working for his very life in the studio of Dunwich Hall! The painter, a man who looks something like Mitter, at any rate, a man of his build; wearing Mitter's painting overalls; not taking any notice of the butler and probably keeping his back to him all the time! Yes, yes, and waited upon by this parlormaid, who is far more than a parlormaid and deep in all the secrets of the house! Oh! how everything can be explained now, and no wonder, when he spoke on the phone to the wife he assumed that hoarse unrecognisable voice!"

He was so thrilled with his discovery that the speedometer touched seventy before he became aware of the speed at which he was travelling.

The following morning he was early in Colchester and Lieutenant Fortescue was pointed out to him just as the latter was coming off parade.

He approached the young fellow and was starting to introduce himself when Fortescue exclaimed—

"Oh! I know you already, Mr. Larose. I met you at Herr Mitter's a few months ago. I was with Captain Johnson and we were talking about coursing. Herr Mitter had just been attending a two days' meeting at Brandon then."

"Of course, of course, I remember quite well," smiled Larose. His face became very serious. "Now I want to ask you a few questions. Where can we go?"

Fortescue took him round to his rooms and Larose at once came straight to the point.

"It's about Herr Mitter that I want to speak, at first," he said. He regarded him intently. "Now does the Herr ever ask you questions about the services?"

Fortescue laughed. "I shouldn't be such a goat as to tell him anything if he did," he replied. His face sobered down and he asked rather sharply. "But what's that to do with you, Mr. Larose?"

"Only that I'm working for the Intelligence Department," said Larose quietly, and he at once proceeded to show him a letter of authority with which he had been provided by Sir Herbert Carnaby.

"Quite O.K.," nodded the lieutenant. He looked puzzled. "But why are you asking me about Herr Mitter?"

"Because he's an agent for a foreign power," snapped Larose, "and, somehow, he's been getting hold of very valuable and secret information."

"Yes, and a very dangerous one," nodded Larose, "perhaps the most dangerous there is in the country at the present time."

"Good God!" exclaimed Fortescue, "but what a startling piece of news!" He shook his head. "No, he's never tried to find out anything from me."

"Well, has anyone else tried?" asked Larose very sharply, and then seeing the young man looking more puzzled than ever, he went on quickly, "But there, I won't beat about the bush. I want to know about that young lady you are friendly with up at Dunwich Hall."

The boy's mouth opened in surprise and then, instantly, he got furiously red. "What do you mean?" he asked angrily. "What are my private affairs to do with you?"

"Come, come," said Larose quietly, "my meaning must be perfectly clear. Has Herr Mitter's parlormaid been pumping you about anything?"

Fortescue appeared to contain himself with an effort. "No," he replied curtly, "she has not."

Larose spoke gently and most apologetically. "Really, Mr. Fortescue, I'm very sorry, indeed, to have to bring the girl up at all, but when you think for a moment, you must see I'm only doing what is perfectly right. We're watching Herr Mitter as a dangerous man and Miss Advent, as his secretary, must be in his confidence to some extent. So what is more natural than that we should suspect she's working with him."

"But I'll swear she's not," exclaimed the boy vehemently. "She's a thoroughly good girl."

"She's a very beautiful one," said Larose, "and looks to me anything but a maid out in service. That makes me the more suspicious." He spoke as kindly as he could. "Now tell me truthfully, has she ever asked you any questions about the army, navy, or air force?"

The boy had settled down now. "Never," he replied. "I swear to you she hasn't." He shrugged his shoulders. "Of course, I've spoken to her about army life and how all my people have been soldiers, but beyond that nothing in that way has ever passed between us. She's never been a bit curious."

"She's never asked you where that invisible glass is being made?" went on Larose.

"Certainly not, and if she had I shouldn't have been able to tell her, for I don't know myself."

The boy looked scornful and shook his head. "I don't know that she is even aware that he exists," he replied. He smiled for the first time. "When we've been out together, Mr. Larose, we've had other things to talk about, as perhaps you will remember, having once been young yourself."

Larose smiled back. "Certainly," he agreed. "I know all about that." He made a gesture of regret. "As I say, she's a very lovely girl and we're very sorry she's mixed up with a man like Mitter."

Fortescue shook his head. "Oh, she's not mixed up with him," he said emphatically. "She'll know nothing of the work he's doing. He's just been kind to her and letting her attend to some of his correspondence, so that she'd be able to learn things and be in a position to better herself." He nodded. "She's leaving Dunwich Hall any week, now."

The boy got very red again. "She's going to London. She's going to a training college in the city. As a matter of fact,—er—-er," he hesitated and then blurted out with some defiance—"as a matter of fact, Mr. Larose, next year she's going to become my wife."

"Your wife!" exclaimed Larose, with an effort restraining his surprise. "Then you are engaged to her?"

"It is understood," nodded Fortescue. He hesitated again and then spoke confidingly. "Now listen, Mr. Larose. You look a gentleman and I've always heard you are one, so I'll take you frankly into my confidence. Miss Advent is no ordinary parlormaid. She's a perfect little lady. She's well educated, and it's just misfortune that she is where she is." He held himself proudly. "Mine is no dishonorable intrigue, and I'm not just 'carrying on' with her. I'm going to do the right thing by her, and so I've found a place where she can start training to become a journalist. Then, when we marry, I shan't be marrying someone who is in service." He nodded vigorously. "Now you know the exact position."

Larose smiled. "And I'm sure you'll be very proud of her." Then his face clouded, and he asked hesitatingly, "But who are her people? Do you know them?"

The boy at once looked embarrassed, and he began to get red again. "Well, I suppose I may as well tell you everything," he said reluctantly. He regarded Larose intently. "Yes, I feel sure I can trust you." He spoke very slowly. "She's a foundling, sir. Twenty two years ago, upon a November the 29th, she was left on the doorstep of the Foundling Hospital. It was the night of the first Sunday in Advent, and that's why they gave her the surname of Advent. The other name, Margaret, was pinned to her baby clothes."

A quarter of an hour later and Larose was hastening with all speed along the London road. He looked very thoughtful, and his face was puckered in a frown.

"If only for that boy's sake, I'd like to believe it," he murmured, "and yet with all that beautiful face of hers. I think—I'm very much afraid she's deceiving him." He sighed. "In all history, down all the ages, women have made fools and playthings of the wisest of men." He grimmaced to himself. "Why, I think that pretty Margaret could even thrill me, if we were thrown much together."

Arriving at the Foundling Hospital, however, and when after some explanations and formalities he was allowed access to the records of the institution, his confident assurance as to the deceit of Margaret Advent received a rude shock.

A baby girl had been left there on the night of November 29 twenty-two years previously, and among other things she had been described as having grey eyes and being of a refined appearance. Also the name Margaret had been written upon a piece of paper pinned to the baby's clothes.

"Hum!" remarked Larose as he left the building, "then I must somewhat revise my conceptions of that young woman." He shook his head doubtfully. "Still, there is nothing more dangerous than a lie, which is half the truth, and after all the very attractive Miss Margaret may be trying to kill two birds with one stone, serving Mitter and advancing herself at the same time."

That night, a few minutes before ten, he crept into the grounds of Dunwich Hall, with the half formed idea in his mind that he might in some way enlist the services of the gardener, Sullivan. He remembered he had tipped the man well when the latter had provided the rose-cuttings for him, and the fellow had seemed very grateful, so it was just possible he might be of use now. Still, he knew, he, Larose, must be very careful, for Sullivan appeared to be a very garrulous individual and hardly seemed a man he would care to trust too much.

The gardener's cottage was at the extreme corner of the grounds and abutted on the high wall of the ruined Priory, indeed, two sides of the cottage were formed by part or the ruins themselves.

Arriving at the cottage, Larose could just see a thin streak of light above the one closely curtained window. He put his ear to the door but could hear nothing. Then suddenly his nostrils were assailed with the strong smell of cigar smoke.

"Hullo! Hullo!" he murmured, "this chap smokes cigars"—he sniffed hard—"and pretty good ones at that!" He looked up at the window. "Now if I could get a ladder anywhere, I might have a squint inside."

There was a misty moon showing and by its light he tip-toed about fifty yards away to a low shed, where lying against it to his great joy, he saw a ladder about eight feet in length.

With infinite precautions that he should make no sound, he carried it across and propped it above the cottage window. Then he mounted, as silent at a shadow. The streak of light came level with his eyes and he could see into the one room of which the cottage consisted.

Then he almost fell off the ladder in his astonishment, for with his first glance he thought it was Mitter himself that he saw!

A man was sitting in an armchair before a good fire, smoking a cigar and with a book in his hand. His face was half turned towards the window and, sideways it had the lines and facial angle of the master of Dunwich Hall.

With a stealthy movement and very slowly, so that he should not disturb the equilibrium of the ladder, Larose drew a small pair of opera glasses from his pocket and focused them upon the man's face.

"By Jupiter!" he breathed in great excitement, "it's not Mitter, but it's the double that I was sure existed! The nose and the mouth are different, but the shape of the head is the same! Mitter and he are of the same blood! They are related to one another!"

Then he stared and stared, until the strain made his eyes ache. The man was wearing a good-class tweed jacket with trousers to match, he had on a clean sports shirt and his feet were thrust into comfortable slippers.

"And it's the gardener!" Larose ejaculated breathlessly. "That's his wig of red hair on the table! Yes, yes, he's Sullivan, the Irishman with the Irish brogue, but no longer the unkempt creature with his muddied face and filthy clothes!" He nodded vigorously. "Oh! but these men do their work well!"

He swept his glasses round the room, noting the big gardening boots that were standing by the wall, the ragged gardening jacket that was hanging upon a peg, and the tattered hat that had been flung upon the floor.

Tempting fortune no longer, he descended the ladder, with the same stealthy footsteps as before, and replaced it where he had found it.

"Now for Mitter's room," he whispered, "and it wants only three minutes to the half hour."

Approaching close to the Hall, he crouched down by the kitchen window, devoutly hoping that Dempster would not fail him or be late.

But he need not have been anxious there, for the butler was quite punctual, and to the stroke of the half-hour from the big clock in the lounge hall, admitted Larose through the window, then pulled it softly down.

"Now, in case I don't see you again," whispered Larose, and he gripped the butler tightly by the arm, "the next time Herr Mitter starts painting be sure you ring up your man in Saxmundham without a moment's delay and tell him to phone me at Carmel Abbey instantly. It's most important. Do you understand?"

"Yes, sir," replied the butler, very shakily. "I'll see that you are informed at once."

They crept through the darkness until Larose was standing just inside Mitter's study door. "And you are sure they are all in bed?" he whispered. "You are certain that parlormaid is in her room?"

"Quite certain, sir," whispered back Dempster hoarsely. "Margaret went upstairs more than an hour ago." He appeared very nervy. "But whatever you do, sir, don't draw the curtains to switch on the lights, for if the master comes home before we expect he will see they are on, long before you are able to hear the car. In fact, you may not hear the car at all, for he may free-wheel right down into the garage with the engine switched off. He often does that so that he shan't disturb any of us when we are asleep. He's very considerate."

"All right, all right," assured Larose. "There's enough moon for me and I've got a torch. Now, you go off to bed and I'll let myself out when I've finished. I shan't be very long," and the butler, as if glad to wash his hands of the whole business, faded away in the darkness.

Larose took a quick glance round the study. The fire was still burning, although it was very low, but the moon was shining through the window and made everything visible, quite plainly.

He walked over to the desk, and with no delay began to try the drawers, but, finding them all unlocked, did not think it worth while to go through their contents. Then before going into the bedroom, the door of which he had noticed was standing open, he lifted up his head and let his eyes rove round to see if there might be anything else of interest to investigate.

Then suddenly he drew a sharp breath, his limbs became rigid, and he stood as immoveable as a graven image—for upon a large settee, not half a dozen paces from him, he saw the recumbent form of Margaret Advent!

The moon shone full upon her, her eyes were closed, and he could tell by the even rise and fall of her bosom that she was asleep. One arm was outstretched and in the hand was a sheaf of papers.

Larose swore softly but deeply in his dismay, realising that he had not noticed her when he had first come into the room, because the back of the settee was half turned towards the study door.

Then instantly he ducked under the desk, for he had seen the girl was stirring and passing a hand across her face. He watched her breathlessly, with his head almost at a level with the floor.

She opened her eyes, brushed the hair off her forehead, yawned, stretched herself and then finally sat up.

She took a glance at the watch upon her wrist, and then noticing the dying fire, rose hurriedly to put on some more coal.

With her back now towards him, Larose seized the opportunity and glided like a shadow through the open door into the adjoining bedroom.

But he was filled with consternation, wondering, if the girl continued to remain in the study, how on earth he was going to get out of the house again before Mitter returned. It looked as if Margaret were waiting up for her master.

He thought instantly of the bedroom window, but he realised quite well he could not raise the sash without her becoming aware of it, for apart from any noise he might make, he was sure the ensuing rush of air through the open bedroom door would immediately attract her attention.

But more dismay followed, for Margaret had only just finished stoking up the fire, when there came the sound of the opening of the front door. Margaret then immediately switched on the study lights and a few seconds later Mitter came into the room. "Hullo!" he exclaimed, "so you've waited up for me!"

"Yes," replied the girl. "I've typed those letters and thought you would want them given to the postman to-morrow, first thing."

Then Mitter spoke sharply, and on the instant his words made Larose's heart beat quicker than ever.

"But haven't you got hold of Dempster's letter today?" he asked. "He must be writing just the same!"

Larose did not hear what answer the girl made, for as he was crouching down in the darkness at the far end of the bedroom, he saw her stretch out a white arm, the light from the study was cut off, and he heard the sharp click of the bedroom door as it was shut to. After that their voices became a low murmur.

Larose gasped. "So Mitter knows he is being watched! He knows Dempster is working for the Intelligence, and sending letters to them! Good God! what fools we've been!"

Now it was characteristic of the nature of Larose that in all his life's work in the tracking down of crime he always took each happening exactly as it came, and never permitted the knowledge of the narrowness of one escape to deter him from embarking upon a further adventure that might entail equal, or possibly, greater risk. So now his pulses having quietened down and his equanimity being in part restored, he made no attempt to get away from Dunwich Hall with all speed, but instead proceeded, most methodically to see if there was anything in Mitter's bedroom that would be of interest to him.

With the quietness of a cat be tiptoed round the room, looking into the chest of drawers, opening a big cupboard, and going through the pockets of the coats hanging in the wardrobe. But he found nothing to reward him until he noticed, lying upon a chair a suit of clothes which be realised in a flash Herr Mitter must have discarded only a few hours previously, when he had changed into his evening clothes for the mayoral dinner.

Quickly he began to search through the pockets, and then in the breast one of the jacket he came upon four letters. Three of them appeared to be of no importance, but the fourth made his eyes sparkle, and his heart jump, for it was addressed to 'Dr. Smith.'

With no hesitation, in the twinkling of an eye, he transferred it to his own pocket, and then with one last look round the room, lifted the sash of the window very softly and stepped into the garden outside.

CHAPTER XII
THE KIDNAPPING OF THE PROFESSOR

FOR nearly a fortnight a watch had been kept upon the house of Dr. Fergus in Trumpington road, Cambridge, and the doctor's young wife, radiant in the possession of her first baby, would have gone sick with terror had she but read the thoughts of the pale-faced and shabby-looking man, from whom, one day, she purchased a pair of boot-laces at the back door.

The man did not appear to her to be possessed of much intelligence, but for all that he was as sharp as a weasel and nothing of any moment escaped his eyes.

He noted that quite a pile of dead leaves had drifted up against the garage door, suggesting to him that it had not been opened for some time, that there were no wheel-marks of any car upon the drive, and that there was no kennel in the yard, or sign that any dog was kept in the house.

Then, quite assured in this last respect, it became his habit to creep into the garden every night, just after dark, peer under the chinks of the blinds and listen at the kitchen window. By these means he learnt that three maid servants were kept, that the cook swore and was an inveterate smoker of cigarettes, that all the three girls made bets upon horses, and that there was no man about the house. He noted also that there was a row of empty beer bottles, from the condition of their labels of not too ancient date, and he saw that this row was not added to at any time during the period of his vigil. So he argued, and quite rightly, too, that the master of the house had not been home for some little time.

He soon came to know all the ways of the house; how the cat was put out every night, punctually at ten o'clock; how all the lights on the ground floor were extinguished at the same time; and how, finally, all the house was in complete darkness within half an hour later.

His mission was to report, instantly, when the absent doctor returned, and as he had been instructed the latter would most certainly arrive in a car, by night, it was at night time only that he kept his vigil, and then, only until about one o'clock in the morning.

He had no idea for what purpose he had been instructed to keep this watch and he did not much care. He had no idea, either, as to the identity or place of residence of his employer. All he knew was, that he was being well-paid for the work by a certain party who had befriended him once, when about a year or so previously he had had come out of prison, and whom he was accustomed to meet, upon receiving a letter intimating that his services were required, at a little coffee shop in Islington.

When he did any regular work, and it was not his habit to over-exert himself at any time, he hawked little trifles from door to door, but he was well-known to the metropolitan police as a pick-pocket and in his short life, he was only twenty-two, had several times enjoyed the hospitality of His Majesty.

The vigil proceeded, without any unusual happening, for twelve days. Then upon the night of the thirteenth, shortly after seven o'clock, the watcher became suddenly of opinion that his work was almost at an end, for through the side of the kitchen blind, he saw one of the maids start peeling potatoes, and the cook put a joint of meat into a baking tin.

"Hullo! Hullo!" he exclaimed with some animation. "High jinks tonight! Saddle of mutton, for the missis, instead of a tray with biscuits and milk! Then the boss is coming home at last!" He nodded vigorously. "I thought those tarts looked togged up and had got clean caps on for once. Generally, they don't seem too tidy to me."

So in a few minutes he shifted his point of observation into a garden upon the other side of the road, where also, he had made it his business to find out, no dog was kept.

Then a few minutes before nine he had the satisfaction of seeing a big car come driving up at a good speed, and a tall man of slight physique jump quickly out almost before it had stopped. Then all in a few seconds the car was turned round and driven rapidly away, the front door of the house was pulled open sharply, a joyous cry came from a woman, with white and gleaming arms, whose figure was framed in the doorway, and the new arrival rushing up the drive, swept the woman off her feet as he proceeded to embrace her.

"A sure thing," remarked the watcher as be peered up and down the road, to make certain it was deserted and then let himself quickly through the garden gate. "That's the hubby, without any doubt!"

So by the following afternoon he had returned to London, and was handing in an advertisement over the counter of 'The Times' office, intimating to all and sundry that a reward of £5 would be given to anyone returning a Fox Terrier who had strayed from his home in Kensington Gardens about 9 o'clock upon the previous night.

The work of the watcher was done, and he was free to return again to his hawking and picking pockets.

Now, in all his daring and well-planned undertakings on behalf of his country, as he always prided himself, Mitter always played for absolute security, and as far as it was practical, allotted each particular piece of work to only one man who, as it were, carried on by himself in a water-tight compartment.

It was only very rarely that two of his agents were allowed to become acquainted with each other, and not one single one of them, beyond the precincts of Dunwich Hall, was aware of the real personality of the man they were working for, or where he actually lived. Upon occasions there was the utmost subtlety, too, in the manner in which he received the information they had been sent out to get hold of.

So upon the morning of the day following upon the night entry of Larose through the kitchen window of the Hall, when the usual morning papers arrived, Mitter turned anxiously to scan down the 'Lost and Found' columns of 'The Times,' and his pulses quickened and his breath came a little quicker as his eyes fell upon the advertisement referring to the fox terrier who was missing from Kensington Gardens.

Then, less than an hour following, Larose received through the channel he had arranged, the information that Herr Mitter had been seized suddenly with another painting urge, and had shut himself up in his studio.

Later in the day, too, the nice mannered and charitably disposed Mr. Howard reappeared in Cambridge, and put up, as before, at the Bull Hotel, arriving there just in time for lunch. During the afternoon he amused himself by sauntering round the town, but five o'clock saw him ringing the bell of the house in Trumpington road, where the rector of St. Jude's lived, next door to the residence of the well-known Dr. Fergus. He carried a parcel under his arm.

He was fortunate in finding that the reverend gentleman was at home, and being ushered into the latter's presence, with a few grateful words for the courtesy he had received upon the occasion of his last visit to Cambridge, he presented to him a beautiful photograph of the reredos of his church.

The old clergyman was delighted, and an animated conversation followed. Then the rector asked Mr. Howard if he were making a long stay in the town this time.

"No, only for a few days," was the reply. "I'm just going to look over some of the other churches and a few of the colleges and, perhaps, if I can manage it, get a round or two of golf."

"Oh! yes, you must visit our golf course," agreed the rector at once. "I don't golf myself, but I am told it is the best course in the country." He seemed most anxious to do anything he could for his visitor, and went on: "Now, do you know any of the members?"

"I'm not sure until I've been up there," replied Mr. Howard. "Then if I don't see anybody I know, I was wondering——"

"Of course, of course," broke in the Rector, anticipating Mr. Howard's next words. "I shall be very delighted, I am sure," he smiled—"and you couldn't have come to a better man, for my nephew, Dr. Rayner, happens to be on the committee. I'll introduce you to him." He looked at his watch. "Now, what about coming straightaway, now. I've got to go to the post office, and it won't be a hundred yards out of my way to take you to my nephew's place. He'll have probably just come in now from his rounds."

So a few minutes later saw the two passing through the garden of a trim-looking little house just off the main road, and with a brass plate upon the garden gate.

"I think we'll go through to the surgery," said the Rector, "and then we shan't trouble anyone to come and answer the bell," and Mr. Howard noted with appreciation the tidiness and spick and span appearance of the little waiting-room and the consulting room that led out from it.

"Very clever and up-to-date young fellow, my nephew," whispered the Rector. "He's getting on well, and will soon be moving into a larger house."

They found the doctor at home, and an introduction being effected, the latter arranged at once to drive the very presentable Mr. Howard to the golf course, the next day at 3 o'clock.

"I get a couple of hours away from the practice whenever I can," he smiled. "You see it gives the patients some chance of getting well."

So the next day Mitter, for of course, he was the Mr. Howard, was made a temporary member of the golf club, and proceeded to keep a sharp look-out for any appearance of either of the two men he wanted.

He had seen Professor Carling at a public lecture when he had last been in Cambridge, and was sure that he would recognise Dr. Fergus both from Tom Skelton's description and also from a photograph of him that he had seen in one of the doctor's scientific books in the Public library.

Besides, if he met Professor Carling on the golf course, he was sure from all he had heard of their friendship, that he would be seeing Dr. Fergus along with him.

And everything happened exactly as he had expected, for coming back into the club house just as it was beginning to get dark, he espied Professor Carling among a laughing group seated at the far end of the lounge and opposite to him a tall red-haired man with a big nose.

There was no mistake about it and he told himself he would have recognised Dr. Fergus instantly even if he had not found the latter in the company of his friend.

He moved as in a dream, as Dr. Rayner piloted him straight towards the men he was so interested in, and then when he sank down in a comfortable chair and the doctor was ordering drinks, he found himself not a dozen paces from his intended quarry, and able to hear distinctly everything that was being said by them.

Naturally, the conversation was all about golf and everyone was chipping Dr. Fergus that he had made such a poor show that afternoon.

"Damn it, man," called out a fat and red-faced individual whom someone had just addressed as Spooner, "but you can't putt for nuts, now. You never were much good, but all the alcohol you've been imbibing has completely shaken your nerve and you're a wreck, even to what you were."

"Wouldn't take your money," retorted Spooner emphatically. "It'd be like robbing a little child." He nodded towards the professor. "And you've upset his game, too, by your bad example. I've never seen so many rotten shots as this afternoon."

Another man broke in. "Let's take them both on for half a dollar, Spooner. They ought to be able to afford that."

"Good! Luscombe," exclaimed Dr. Fergus, "we agree." He winked at the professor, "and as we are the challenged parties, we have the choice of weapons, time and place." He glanced in mock severity at Spooner. "So we appoint to-morrow, here, and at 8.30 sharp."

"Great Jehosophat!" groaned Spooner. "8.30 on mornings like these! Why, man, I don't get up till nine o'clock!"

"Your habits, sir," commented the doctor coldly, "are of no concern to us. You have insulted us, and, accordingly, you must abide by the consequences." He thumped upon the arm of his chair. "Tomorrow, at 8.30, and if you and Luscombe don't show up to the minute, sharp, we shall know you are both afraid and the penalty will be degradation in the eyes of all here and a dinner at the 'Bull' for six on Saturday night."

"All right!" laughed Luscombe, "we'll be here." He turned to Spooner. "So, I'll call for you, my boy, at 8.15 sharp, and bring you along in my car." He nodded grimly. "And if you're not dressed when I appear before your house, you'll come as you are. Understand?"

Spooner grunted stertorously. "But it'll kill me!" he groaned. "The morning air will be deadly to my constitution!"

"And mind," warned Dr. Fergus, "if you are not here to the minute, we shall take it you are not coming. We shan't wait."

"All right," said Luscombe frowningly, "but if we don't turn up you will understand a tragedy has happened, for then"—he glanced at the stout man and spoke very solemnly—"I shall have murdered the wretched creature here."

And all the while Mitter had been listening to their banter in a perfect fever of excitement, hardly hearing a word of what Dr. Rayner had been saying to him.

The very opportunity be had been hoping for! But he couldn't deal with the four of them. He would only be having two men to help him and there must be no bloodshed and no signs left to show that the doctor and the professor had been forcibly taken away! The whole success of the undertaking depended upon there being no immediate pursuit, and when the hue and cry was raised there must be no point for the pursuers to start off from!

His pulses quietened down. Then these two friends of theirs must be prevented from coming to the golf course on the morrow. That was all. It must be managed somehow.

Arriving back in the town Mitter's first act was to consult a telephone directory and he was much heartened to see that there was apparently, only one householder of the name of Luscombe in Cambridge.

So about twenty minutes later, a quick walk had brought him to the vicinity of that gentleman's house and he arrived there just in time to see Luscombe himself turn into his drive and be vociferously welcomed by a big Irish terrier.

No one passing at the time, Mitter stopped, and peering over the low wall was able to make out, by the light in the road, all that followed.

Luscombe drove his car into the garage and switching on the light there, proceeded to empty the contents of two petrol tins into the tank. Then after taking a quick look round at his tyres, and adding some water to the radiator, he switched off the lights again and having pulled to the garage door, returned up the drive to shut the gates. Then he let himself into the house, leaving the dog, however, to remain outside, and the latter, after sniffing about for a minute or two, betook himself to a large kennel that was close by the garage, and lay down.

Mitter did some quick thinking. It was in his mind to put the car out of action, somehow, so that it would not start the next morning, but the presence of the Irish terrier presented a great difficulty.

Then suddenly he looked at his watch and his face breaking into a broad smile, he set off at a quick pace back towards the town.

His walk this time was very short, and five minutes brought him to the vicinity of Dr. Rayner's house.

"Ten minutes past six," he muttered, "and as his surgery hours do not commence until half past, I may just have time, before any patients begin to arrive."

He noticed there was a car parked in the road before the house and he at once recognised it was the doctor's and the one that had taken them to the golf course that afternoon. Then he was upon the point of turning into the garden, when a thought struck him, and he slowed down and then stopped dead.

He waited a few moments for a woman with a little child to pass, and then approaching the car, opened one of the doors and bending down inside, struck a match, evidently to see if he could find something.

But his scrutiny was very short and, apparently disappointed, he quickly, but very softly, closed the door, and turning into the garden, proceeded to walk up the path.

He did not approach the front door of the house, but turned off towards the surgery, through which he had entered the house the previous afternoon, along with the doctor's reverend uncle.

There were no lights up in the surgery, but trying the handle of the door, he found it unlocked, and so, making no sound, he passed quickly inside. He closed the door very softly behind him and then for a long moment stood listening. Then finding everything perfectly quiet, his movements became quick and business-like. He struck a match to get his bearings, but then blowing it out again at once, he glided across the waiting room, keeping one hand upon the wall so that he should not bump into any of the furniture.

He gained the farther room where the doctor attended to his patients, and then struck another match, this time, however, keeping it alight until it had burnt almost to his fingers. He was looking for some cupboard or some drawers where the doctor would be keeping his drugs, for he wanted morphia tablets to dope Luscombe's dog.

He struck another match and then immediately gave a deep and satisfied "A-ah!" for he had seen a professional looking black bag upon a chair just by the desk.

In two seconds he had laid his hands upon the bag and was tip-toeing to the window, where he saw there would be just light enough from the stars to go through its content.

He soon found what he wanted, a small leather hypodermic case, and opening it carefully, he stirred among a number of little phials to find one that contained morphia.

Ah! There it was—with the label 'Morphine sulphate, ¼ grain.' He slipped it into his waistcoat pocket, and closing and replacing the leather case, returned the bag to where he had found it. Then he tip-toed back into the waiting room and, his eyes now more accustomed to the light, had no need to strike another match.

He had almost reached the door leading into the garden when happening to glance through the window, the blind of which had not been drawn—his blood froze in horror as he saw a policeman striding resolutely up the garden path and making straight for the surgery door.

For one moment he stood as if paralysed, but then quickly recovering his wits, he darted over to the wall and switched on the lights. Then he dashed his hat down upon the table, picked up a magazine from among a number there and flinging himself back into a chair, stretched out his legs and apparently commenced to read with great intentness.

The door opened and the police-man stepped into the room. He was a good looking young fellow with a very intelligent face. Mitter just looked up casually for a quick moment, and then let his eyes drop again upon his magazine.

Mitter looked with a start now, and regarded the policeman with a very astonished look. For a moment he did not speak and then he asked quietly. "What did you mean?"

"What are you doing in this room?" repeated the policeman, and there was no softening in the sternness of his tone.

Mitter seemed the more surprised. "Waiting to see the doctor, of course," he replied, and then added as if he were annoyed at the question being put. "What do you want to know for?"

"Are you a patient?" asked the policeman, ignoring Mitter's question and with his eyes boring like gimlets.

For answer, the policeman closed the door in a most decisive manner and then proceeded to press his finger on a bell-push that he saw upon the wall. He kept his finger on the bell, too, and a loud, insistent burr came echoing from another part of the house.

Immediately then there was the sound of hurried footsteps, the door leading from the hall into the consulting-room burst open and Dr. Rayner ran into the waiting room. From the movements of his jaw he had evidently been disturbed in the middle of his meal.

"Know this man, sir?" jerked out the young policeman, pointing to the now broadly-smiling Mitter.

"Yes," exclaimed the doctor in great surprise. "Is he hurt? Has he met with an accident?" and then noting the expression upon Mitter's face, he added smilingly:—"He doesn't look like it!"

The policeman's face fell. "Then you do know him? He's a friend of yours?" he asked.

"Certainly," replied the doctor. "We've been golfing together this afternoon." He eyed the policeman frowningly. "But what's this all about?"

The policeman looked sulky. "This gent was acting very suspiciously. I was watching over across the road and he didn't know I was there. First, he came up to your car and stood waiting about until a woman with a child had passed. Then, all of a sudden, he jumped up to the car and opened one of the doors. Then I saw he was striking a match. Then he closed the door quietly—much too quietly, I thought—and crept up the pathway here. Then he came inside and I saw he was striking matches again. I was coming after him pretty quick, but he switched on the light just before I got here."

"But I think I'd better explain, Dr. Rayner," interrupted Mitter hastily, and with a very apologetic expression upon his face. "It's really all my fault, and I realise now that the constable here was perfectly justified in becoming suspicious. What happened was this. I lost my reading glasses somewhere this afternoon, and was coming along in the hope that I might perhaps have dropped them in the car and you had found them. Then when I saw your car outside, I thought I would look there before coming in." He laughed. "In here, I couldn't find the switch at first, and that's why the officer saw me striking matches again. I intended to wait until the surgery opened so as not to disturb you at your dinner."

The constable went out, somewhat mollified by the five shillings Mitter had given him, and a minute or two later Mitter himself took his departure.

"By Jove!" he whispered, as he turned into the road, "that was a near thing." He nodded. "Still, my good fortune is holding!"

His next move was to visit a butcher and buy a pound of steak. Then in the privacy of his bedroom at the hotel, he made up succulent little baits, each one containing a grain of morphia and tied round with a wisp of cotton that he had drawn out from one of the sheets upon the bed.

So it happened that about half-past eight that night Mr. Teddy Luscombe's Irish terrier was disturbed from his slumbers by the rattling of a stone upon the cement drive, and with a low growl he came out of his kennel to see what it meant. He had been digesting what he considered a very inadequate meal, for there was a wide difference of opinion between him and his master as to what constituted a good dinner for a dog of his size.

He padded out on to the drive, and immediately another stone came rattling, this time a little nearer to the gate. Then he saw something white bobbing about near the foot of the wall, as Mitter jigged a ball of rolled up newspaper at the end of a piece of string.

He accelerated his pace, and with a snappy bark made a vicious plunge at the paper, but it just eluded him as it was drawn up quickly over the wall. Then, as he was growling deeply, a piece of meat fell right under his nose. He stopped growling to sniff hard, and then, no further noises ensuing, and there being no reappearance of the roll of paper, after well nosing the piece of meat for a few more seconds, he picked it up, champed his jaws half a dozen times, and swallowed it.

"No, no, my good dog," murmured Mitter, as he started to walk briskly up the road, "one's quite enough for you, and you mustn't be made sick. Now I'll give you an hour, and then you'll be fast asleep."

So, just an hour later, undeterred by the dog, who was now sleeping heavily, Mitter let himself into the garage, and by the light of a small torch, and with a wrench and a screwdriver that he had brought with him, proceeded methodically to put the car out of action. He made no gross interference with anything, but, taking out three of the sparking plugs bent their points so wide apart that the engine would miss badly when the next attempt was made to start it.

Then closing to the garage door very softly, he next proceeded to climb the wall at one end of the garden where he had seen he could reach the telephone wires running from the house. Then he manipulated the wires, until one of them was crossing over the other, by that means effectually putting the telephone out of action until the wires were disengaged again.

Then he returned to the hotel and announcing that he had unexpectedly been called away, paid his account and drove off in his car.

Not long after eleven found him in a low, rambling house upon the banks of a small mere, a little less than sixty miles away, and in earnest conversation with two men. These latter had only known one another for a few days and neither of them were acquainted with the other's real name. As Mitter had been advised, they had each of them in turn been warned, for their own security, to disclose as little as possible about themselves and as they were quite aware they were to be involved in some highly unlawful undertaking, they had seen the expediency of the advice, and so no confidences had been exchanged during the time they had been waiting for their unknown employer to appear.

They were both strong, burly men, one of them looking like a pugilist, which indeed he had been once, and the other might have worked on the dockside. They knew they were going to be well paid for their services, and as 'habituals' among the criminal classes, they were not particular as to what they would be given to do. They had never gone a hundred yards from the house since they had arrived, and their sole occupation, apart from their meals and sleeping, had been fishing from the bank of the mere.

The conversation now between the three was long and earnest, and although the house was isolated and very lonely, it was carried on all the time in low whispering tones. Silence and night are always the fitting environment for unlawful deeds.

DR. BENJAMIN FERGUS had arrived home for his little holiday in a very joyous frame of mind, and with all his thirty-four years of age and his scientific attainments, he was like a big schoolboy in his happiness. He danced round many times with his young wife, jigged the baby up and down until it was sick, and wished the postman, whom he heard had just got married, a long family and plenty of twins.

He lost no time in going round to see his great friend, Professor Carling, and his spirits were exuberant, there, too.

"Everything going splendidly on the island, my boy!" he exclaimed. "Things couldn't be better, and we never get a bad mix now. The stuff comes out O.K. and A1 every time. No, we've had no more shocks since that sentry was killed, but, of course, they found out nothing. The Intelligence people sent down an extra special johnny to investigate. No one knows who he was, but we called him Mr. X, and he was a very decent fellow. He dined with us all the night after he arrived, and was about the most entertaining chap I've ever met. He told all of us our characters, read our family histories from our clothes, and showed us how to cheat at cards and pick pockets."

"Might have been, but he was certainly not an ordinary one. He was well dressed, and very well informed upon every subject we discussed. The old colonel said afterwards that he was disguised, and he was sure his moustache was not a real one, because he sipped so delicately at everything he had to drink." The doctor slapped his friend upon the back. "But now, my lad, what about some golf this afternoon? Good! Then I'll come round for you after lunch."

So that afternoon and the two succeeding ones, were spent upon the golf course, and the third afternoon upon returning, when it was dark, to the club-house, over whiskies and sodas and much laughter and badinage, the challenge of the light-hearted Teddy Luscombe was accepted for the match upon the morrow at 8.30.

The following morning, sharp to the time specified, the two friends were upon the course waiting for their adversaries to appear.

"They are not coming, of course," said Dr. Fergus, when ten minutes had passed, and there was no sign of any car upon the road. "I thought that lazy beggar Spooner wouldn't turn up. He's no life in him until he's had a spot or two. Come on, we won't wait any longer. We'll get on with our game."

So declining to take any caddies with them, they started off, and did not encounter a single person until they had dropped down in the little hollow where the seventh putting green was situated, and then three men came in sight over the rise and began to walk in their direction.

The arrivals appeared to be men whose occupation had to do with telephone or telegraph repairs, for one of them carried a coil of shining copper wire and the other two had big tool bags slung over their shoulders.

Approaching close to the two friends, one of the men, a big burly fellow, touched his cap and asked hoarsely of Dr. Fergus, "Which is the way to the club-house, please, guv'nor. We've got a job on there," and then when the doctor turned and pointed out the direction, the burly man's arm shot out like lightning and the doctor received a vicious blow upon the angle of his jaw, that knocked him unconscious to the ground.

At the same moment the small-framed professor was seized roughly round the waist by a second man, jerked off his feet, and a large horny hand was placed over his mouth.

"You shout," enjoined a gruff voice fiercely, "and I'll throttle you! Keep still and you'll come to no harm," and at the same time the professor's arms were pulled sharply behind him and he heard the click of handcuffs, as they were locked upon his wrists.

It was all over in less than half a minute and then the professor, realising that it was quite hopeless to struggle or shout, found himself flung over his captor's shoulder and being hurried across to a large car that was waiting on the road about a couple of hundred yards away. Finally, he was bumped down upon the floor at the back of the car, a length of rope was coiled round his legs, and he was again warned to keep quiet.

A minute or so later, Dr. Fergus, still unconscious, was carried up and laid down beside him. Then a short delay occurred while one of the men ran back and collected the golf clubs of the two friends and then the car was started and quickly accelerated to a good pace.

A man who appeared to be the leader, and who had got a scrubby beard and was wearing dark glasses, bent over the doctor and placed a folded rug under his head. "You hit him pretty hard, didn't you?" he growled in an angry tone to someone over his shoulder.

"No," came a voice from the front seat, "just a touch. He'll be all right in a few minutes. But I had to make quite sure."

Then the man who had first spoken, produced a bandage and tied it over the professor's eyes. "No, don't waste your breath in talking," he said. "We'll explain everything presently."

Then it seemed to the professor that a very long time passed, until the car stopped, and he was lifted once again and carried for about two hundred yards. Then he knew he was being taken into a house, and finally he felt himself lowered on to a bed. He was told not to move, the speaker adding that he would return again in a few minutes.

But Professor Carling had no inclination to move, for terror and consternation had, all suddenly, gripped him and he was filled with the most dreadful thoughts. What was the meaning of the outrage? he was asking himself, and the only answer he could give covered him in a cold sweat from head to foot.

He and Dr. Fergus had been the discoverers of that invisible glass and save them, it would have been well nigh impossible to find in all England, two men who knew the secret, at one and the same time, in the same place together.

What if it were an attempt to get hold of the formula from them, who, of all others, were best able to give it?

He gritted his teeth together and some strength seemed to come back to his shaking limbs. Well, they would never get it from him, he resolved, and if he knew anything of the character of his friend, the latter, too, would die rather than speak a word.

In the meantime Mitter, for one of the men had been he, with a very troubled expression upon his face, was endeavoring to restore to consciousness the unfortunate doctor who had been knocked down by ex-bruiser of Shoreditch, Mr. Samuel Dukes.

But the redoubtable Sam had struck well and truly, and his confident prediction that his victim would be all right again in a few minutes was not being fulfilled.

"You fool! I tell you, you struck him too hard," exclaimed Mitter. "He's not a rough lot like yourself and it may be days before he comes to!"

"Not a bit of it," retorted Dukes sullenly, as he flapped vigorously at the doctor's face with a wet towel. "I tell you I didn't hit at all hard. It's only just that the gent is soft from an easy life and too much good living."

Making no reply, Mitter left him at it and made his way to the adjoining room where the professor had been taken. He closed the door very carefully behind him, and, approaching the bed, first changed the handcuffs upon the professors wrists, over from back to front, and then removed the bandage from the professor's eyes.

"Sit up," he said, as he sat himself down upon the single chair the room contained, a few paces distance from the bed.

The professor, with a scowl, shuffled over to the edge of the bed and did as he was requested. Then he eyed Mitter intently, his face, however, betraying none of the fears and suspicion that he felt.

"Now you listen to me," said Mitter, "and I'll come straight to the point." He paused impressively for a moment. "You're Professor Carling, and your friend is Dr. Fergus. Well, we've brought you both here to obtain the formula of that new glass that's being made and that you invented. No, no," he went on sternly, because the professor had at once shaken his head, "the understanding between us must be quite clear, for the sooner you realise your exact position, the better it will be for you."

"You damned ruffian!" burst out the professor furiously. "I know nothing about the glass, nor does Dr. Fergus either. You're mistaken there."

Mitter shook his head. "Don't be untruthful, Professor," he said quietly, "and don't work yourself into a rage. We know all about you both, everything, and we've known it for a long time, and have only been waiting to act until we could get hold of both of you together. You and Dr. Fergus are the co-inventors of the material and its discovery was made in your laboratory in Cambridge. Dr. Fergus is now directing its manufacture upon Foulness Island, and has been so doing since March last. He came home only the day before yesterday, upon a few days' leave." He smiled. "This is no haphazard affair, my friend, but has been most carefully prepared for. So——"

"But you won't get anything out of us," broke in the professor fiercely, and no longer attempting any denials. "We're not that sort of men and so you've had all your trouble for nothing." He snarled. "Good God, this means 20 years' imprisonment for you." A thought seemed suddenly to strike him and he asked with blazing eves, "Who are you?"

"A very humble person," smiled Mitter, "but who I am is neither here nor there." He went on. "So the position is this. We have you both in our power and are resolved that neither of you shall be given your liberty until the formula has been obtained from each one of you in turn. There will be no chance of your deceiving us, for you and your friend are going to be kept apart, and we shall be sure then that you are giving accurate information, because the two formulas will have to be exactly the same." He nodded. "You grasp that—you have taken it in?"

"I'll give you no information," exclaimed the professor scornfully. "I'd rather die first."

"It is not exactly a question of dying, Professor," said Mitter quietly, "for we don't anticipate for a moment you will force us to that." He shrugged his shoulders. "Of course we realise that by kidnapping you like this we have exposed ourselves to very severe punishment if we are caught, and therefore"—his voice hardened—"you will understand we shall not shrink at the most extreme measures if they become necessary." He shook his head smilingly. "But we don't want you to die, or, indeed, suffer in any way. We just want you to be sensible men, and, seeing that you have no choice in the matter, to give us the information without any bother." He spoke quite pleasantly. "Then I promise you you shall be set at liberty within two hours, so that you can be back at your homes again tonight." He looked amused. "And if you both keep your mouths shut, no one need even know that you have told anything."

"You devil!" exclaimed the Professor, "do you think Englishmen would do a thing like that?"

"Husbands and fathers might," smiled Mitter—he nodded significantly—"that is, if they want to see those dear to them, again."

"And if we don't do as you want us to," asked the Professor in amazement, "do you really mean to tell me you will kill us, that you threaten us with murder, in fact?"

Mitter spoke as if they were discussing a very ordinary matter. "Not straightaway," he replied quietly—he lowered his voice almost to a whisper, and eyed the professor very intently—"for we should try other measures, first, to bring you to your senses."

Mitter shrugged his shoulders. "This is no child's game," he said sternly. "We are in deadly earnest, I say, and I tell you frankly there are no lengths we are not prepared to go if you compel us to do so." He shook his head frowningly. "But there, we'll not talk of that, for I am sure you will not be so foolish as to make us resort to such extremes." He rose up from his chair. "But now, I'll leave you for an hour and you can think it over. I'm going to have a talk with your friend." He pointed to the window, which was heavily barred. "But don't think for a moment that you can play us any tricks. You see you can't get away and there is no possibility, either, of anyone finding out where you are hidden. You are miles away from anywhere." He smiled a very pleasant smile. "We've been a long while arranging for this, as I say, and have provided for everything."

Returning to the other room, Mitter found there was no improvement in the doctor's condition, for the latter was still unconscious, with a very faint pulse and almost imperceptible breathing.

Dukes had stopped flapping with the towel, and was now regarding the unconscious man with a decidedly uneasy expression upon his face.

"Cripes! if he croaks!" he exclaimed as Mitter entered. "It'll be a bad thing for all of us."

"Oh! he's not going to die," said Mitter testily, "and you ought to know that well enough. The annoying thing is he may remain like this for days and not be able to speak."

"If I knocked a chap out in a fight," went on Dukes meditatively, "it never troubled me a bit, but a gent like this, who I say has been living soft"—he nodded gloomily—"well, I don't like that bluish look about his face."

"Well, you go outside," said Mitter, jerking his head in the direction of the door. "You're no good here now, and the only thing we can do is to wait. He may come to any minute and then we can all clear out tonight." Then seeing that Dukes seemed in no way reassured, he added, "I know enough about doctoring to be quite certain he's not badly hurt."

The day passed very slowly, with the doctor still unconscious and every hour increasing Mitter's annoyance. He had hoped to have got everything finished that day and, with the formula in his possession, to have left the house along with his two confederates directly it was dark.

He had been intending to drug the kidnapped men heavily, and leave them to come to and get away as best they could. He had reckoned no stir would be made about them in Cambridge until long after nightfall, for he had learnt that when upon the golf course they often played there all day.

So he had been expecting to have been back again in Dunwich long before any hue and cry had started.

But now all his arrangements were upset and when darkness fell and there was no change in the doctor's condition, his annoyance first deepened into anxiety and then into real consternation.

He had not visited the professor again, deeming it best to allow the latter to work himself into such a state of worry and apprehension that his will would be so weakened he would give in without any trouble.

The night passed with no one in the house getting much sleep, indeed, the professor never closed his eyes. Mitter dozed fitfully in an armchair. Dukes smoked pipe after pipe, wakeful and full of fears, cursing all the time that any sum of money had brought him into such an adventure, and Fletcher, the second man, realising how disturbed the others had become, was too uneasy in his mind to sleep more than a few minutes at a time.

The next morning the prospect seemed a little brighter for, although still unconscious, the doctor's pulse was stronger and his breathing decidedly better.

Then, too, Mitter took heart at the thought that if the best detective talent in the kingdom had been called in, there was not one clue they could pick up, and they would be absolutely fogged where to start off from. Yes, he told himself, he was in absolute security, even if he had to wait a week for the doctor to become conscious.

And so the second day wore on, and night fell again, without much change in the doctor's condition. He still remained unconscious.

CHAPTER XIII
THE HEATED IRON

NOW Mitter had made a grave miscalculation when he had so comforted himself with the thought that no anxiety would be felt about the kidnapped men, until long after darkness had set in.

On the contrary, they were being looked for by half-past nine that same morning, by eleven o'clock the local police had been called in, by twelve Scotland Yard had been communicated with, and by two Gilbert Larose had come tearing into Cambridge at a whirlwind speed.

Colonel Bevan, of the Air Force, had had an appointment with Dr. Fergus, in Trumpington road at eleven o'clock that morning, but arriving at the doctor's house an hour earlier, he had learnt that the latter was golfing with Professor Carling. Thereupon, being solicitous of completing his business with the doctor as speedily as possible, because an unexpected and important matter had cropped up in town, and he wanted to be back there in the early afternoon, he had followed after him, in the expectation that they could have their conversation straight away.

It fitted in well, too, that he would catch Professor Carling at the same time, because the latter's opinion upon the matter they were going to discuss was desired also.

Then upon arriving at the golf course he was at once told an extraordinary and, to him, rather disquieting tale.

It appeared that Dr. Fergus and the professor had arrived there, in the former's car, exactly at half past eight, and ten minutes later, declining to take any caddie with them, as was their invariable custom when they played alone, had started out upon a game. Then, at half past nine, two friends of theirs, a Mr. Edward Luscombe and a Captain Spooner, had appeared upon the scene. These last gentlemen should have been upon the course at the same time as the other two, to keep an appointment for a foursome, but Mr. Luscombe had had some trouble with his car, and hence the tardiness of their arrival.

Mr. Luscombe and Captain Spooner, being so long behind their time, had not expected that the doctor and the professor would be waiting for them, but as they realised some explanation and apology were needed for their failure to keep the appointment, they had proceeded, with all haste, to cut across the course to pick up their friends. Also, as the promised game was only to have been a friendly one, they were expecting to probably join in when they overtook them.

But they could see no sign of them anywhere, and then one thing which struck them as very extraordinary, was that about twenty yards from the seventh green, which lay in a dip of the course, they came upon a ball already teed up upon the teeing ground, and, from all appearances, the ball had but very recently been placed there.

Colonel Bevan heard all this in the club house to which the two late arrivals but a few minutes before had returned to ascertain if by any chance their friends were refreshing themselves inside.

"And they can't have gone away from here, sir," exclaimed Captain Spooner to the Colonel in great perplexity, "for the doctor's car is still there," and he pointed to a smart little two-seater parked close by.

"And yet they can't be here," grunted Luscombe, "for all the fairways are in full view and we can pick out everyone upon the course, except when they're down by this seventh green."

Then when, at his request, Colonel Bevan was taken over to the seventh green and he saw how secluded it was and how near too to the main road, he became most apprehensive at once and, returning to the clubhouse with no delay, put through a call to the Superintendent of the Cambridge police.

"You see, gentlemen," he exclaimed to some of the members of the club who were standing round, "it may turn out to be a very serious matter, as Dr. Fergus is engaged upon highly important research work for the Government, and there are not a few people"—he nodded significantly—"who might wish him ill."

The Superintendent, along with two plainclothes men, was upon the scene in a very few minutes, and Colonel Bevan drawing him to one side, very quickly made known to him who he was, and the significance of the two men's disappearance.

"From a Government point of view," he added, "there are, at the present moment, no two men of greater importance in all the country, for they are in possession of secrets that are being closely guarded and are known only to a very few."

The Superintendent was impressed, and another visit was at once paid to the seventh green.

"You see they got as far as here," explained Captain Spooner, who already was regarding himself as a sleuth of the first water, "and no farther, as evidenced by the ball left upon the tee. Something happened here to stop their game."

"But how do you know the particular ball you found belonged to one of them?" asked the Superintendent sharply.

"Because they were the first to start playing this morning," replied Spooner, "and then we got to the green before any other players did. You must understand that when we were looking for them, and did not see them anywhere on the fairways, we made direct here, because, as you have seen, it is the only place on the whole course where players are out of sight. Besides," he added triumphantly, "the ball was quite dry when I picked it up, and if it had been here all night it would have been wet from the dew."

A minute search was made over the ground in every direction, and especially towards where the road lay, but nothing unusual was noticed, and as there had been no rain for some days, no footprints could be picked out.

"And that's the road leading to Newmarket," nodded the Superintendent to Colonel Bevan, "and hundreds of cars pass here during the day. So if there was any abduction with violence, there's just a chance someone may have seen something suspicious, and we shall get information when their disappearance is put upon the air."

"Oh! but surely in that case you would have heard of it by now, Superintendent," suggested Spooner. He shook his head judicially. "No, I'm afraid there's no hope there, for although, as you say, during the day hundreds of cars do pass along this road, when playing here I've often noticed that it is deserted for quite a long period at a time."

Returning once again to the club-house, Colonel Bevan was now in such a state of apprehension that he immediately rang up and got in touch with Mr. Grant. The latter at once took the gravest view of the situation, and with no delay, proceeded to put in motion all the machinery at his command.

So it came about that a few minutes after two o'clock, Larose drove up to the club-house and learnt from the secretary of the club that an enquiry was being held in the committee room at that very moment.

"Who's there?" he asked sharply, after disclosing who he was and explaining that he was acting for the Intelligence Department in Whitehall.

"Superintendent Woods of Cambridge," replied the secretary, "and Chief Inspectors Carter and Stone from Scotland Yard. They've just been questioning our Captain Spooner and Mr. Luscombe."

"All right," nodded Larose. "I know the inspectors, and please take me in at once." He smiled. "They won't mind being interrupted and will be quite pleased to see me."

And certainly the inspectors showed all signs of pleasure when Larose was ushered into the room. They appeared to be a very ill-assorted couple, for Carter was tall, thin and lanky, with a rather severe case of countenance, looking not unlike a nonconformist minister in mufti, whereas his colleague, Stone, while nearly as tall, was so stout of figure that his real height was not apparent. Stone, too, had a jovial, humorous face, with a large mouth, and eyes seemingly as big as those of an ox.

They both greeted Larose in the most friendly way, and Stone at once introduced him to the Cambridge superintendent.

"We were told you were coming down," he boomed, with his eyes twinkling, "and I suppose we shall have to put up with it." He turned smilingly to the superintendent. "This gentleman, sir, has got the evil eye and is supposed to be able to see through a brick wall. He was hard up and needy like me once, but now he's got pots of money to throw about, and only gets poor devils hanged for the sport of seeing them take the drop."

Chief-Inspector Carter explained quickly to Larose all that had happened, and gave it as his opinion that the two missing men had been kidnapped.

"Of course they have," agreed Larose instantly, "and the whole matter has been most carefully prepared for." He nodded to both Carter and Stone in turn. "This is, of course, the beginning of a trail to you, but to me it is only the continuation of one I have been following up for weeks." He glanced towards some notes that he saw Carter had been taking. "Now what do you make from what this Captain Spooner and Mr. Luscombe have been telling you?"

Inspector Carter spoke quite confidently. "That the kidnappers were expecting the doctor and the professor, together with their two friends, to be along here early this morning, and accordingly made all preparations to seize them at the only place upon the golf course where they knew they would be out of sight of the clubhouse."

"There are always a few caddies waiting there," supplemented Stone, "in fact, this morning there were seven of them, when the two men arrived."

"Therefore," went on Carter, "two things stand out quite clearly; the first—that the kidnappers have a confederate somewhere in the club, who has been standing by to report all movements of the wanted men, and the second—that the kidnapping gang must be a fairly large one, as they were undoubtedly prepared to have to lay violent hands upon four men."

"The latter supposition appears pretty obvious, Mr. Larose," explained Stone, "for it was by chance only, that Messrs. Spooner and Luscombe were not here, as arranged, this morning. If Mr. Luscombe had not had unexpected trouble in getting his car to start, both he and the captain would have been here sharp to time."

Larose shook his head. "But if these two men have been kidnapped," he said, "as it looks almost certain they have been, then, as I will tell you in a few minutes, I know something about the man that carried it out, and I am not inclined to put much faith in anything having been done by chance as you say." He rose up from his chair. "At any rate, I'd like to be quite satisfied on that score and therefore, if you don't mind, we'll have this Mr. Luscombe back and I'll ask him a few questions myself."

"Then get about it, my son," said Stone pleasantly. He winked at the superintendent. "We knew we are all as little children in your hands."

So a couple of minutes later, both Luscombe and Spooner were back in the committee room and had been accommodated with chairs.

"Mr. Gilbert Larose," explained Carter to them, "is an old Scotland Yard man and he has worked with us upon many cases. So I am sure you won't mind him going over the same ground again."

"Certainly not," agreed Captain Spooner heartily. "In fact, I'm sure we are very pleased to meet him. We've heard about him, of course."

Larose smiled at the compliment. "Now, sir, naturally it was no secret," he began, "that you were going to play this foursome this morning?"

"Rather not," laughed Spooner, "we challenged them openly in the lounge last night, when lots of other members were present. Besides, I arranged with the caddy-master for four caddies to be waiting for us this morning. You see, the time, half-past eight, was a bit early, and so special arrangements had to be made to be certain the boys would be ready waiting."

"You say a number of the members heard you arrange the meeting," said Larose. "Then do you know them all?"

"No strangers to you," suggested Larose, "and all like a happy family together."

"Here, you just wait a moment," interrupted Luscombe. "You're not correct there. Dr. Ryder had got a friend with him, a stranger, and they were having drinks just behind us, as we were talking."

"Oh! a stranger," exclaimed Larose. "Then what was he like. Will you please describe him."

Luscombe considered. "Heavy-looking, stout man. About middle-age, I should say. Very dark skin and wore smoked glasses. Looked a gentleman"—he grinned—"but not much of a golfer."

Larose repressed the exultation that he felt. "What was his voice like? Did you hear him speak?" he asked immediately, and then when Luscombe shook his head, he went on. "And who's this Dr. Ryder?"

"A chap who's just started practising in Cambridge. Very nice young fellow, and he'll probably be up here in a few minutes. He hasn't many patients as yet, and generally gets in a bit of golf every afternoon."

"Good!" exclaimed Larose, "then we'll have a talk with him." He changed the conversation. "Now Mr. Luscombe, but for the difficult starting of your car, I understand you would have been here to time this morning, and then your friends would not have been found alone, as, unhappily, we have to presume they were, upon the seventh green. Well, what did you find was the matter with the car when you went to start it?"

"The points of some of the sparking plugs had worn too wide apart, and I could only get the engine to start after a lot of difficulty, and then it missed badly."

"But do you think the points have been tampered with?" asked Larose with a frown.

"No," replied Luscombe. "I am hardly of——" but then he hesitated and stopped. "By Jove!" he exclaimed after a few seconds, "but I remember it did strike me at the time as being a bit queer, for three of the plugs, one after another, had got a devilish big gap." He shook his head. "But, no, no one could have got at the car during the night, although the garage was certainly not locked, for my big Irish terrier was sleeping close near." He frowned heavily, and went on speaking very slowly. "And now you put these ideas into my mind, I thought the dog was as dopey as an owl this morning, for he just crawled out of his kennel to wag his tail, and then went back."

"Just after eight. I was up extra early, for I had to call for my friend here, and particularly wanted to be punctual for our appointment. Both the doctor and the professor are very fussy about time, and I know they would take it we were not coming, if we weren't sharp to the minute. I tried to ring them up, when I found the dashed car wouldn't go, to ask them to wait, but, of course, the phone was out of order, just when I wanted it."

"Yes, the wife rang up, about 12, to know if I were coming home to lunch. She said the telephone men had found the wires were crossed."

Without comprehending the exact drift of the question. Luscombe nodded. "Yes, just over the wall of the garden," he replied, "under a big tree."

"Thank you," nodded Larose, "that is all I want to know," and when the two friends had left the room, he turned to the detectives. "And I think," he said grimly, "we shall find that visitor to the club will turn out to be a Herr Mitter, of Dunwich Hall, a secret service agent for a foreign power, whom I have been trailing for three weeks, and with whom I had lunch only two days ago."

"We were sort of informed," laughed Stone good-naturedly, "that you would be taking the helm when you came on deck, so just put us wise to all you know."

And then Larose proceeded to tell very briefly and omitting all unimportant details, much of what he had been finding out about Herr Mitter. He had come almost to the end of his recital, when he was interrupted by a knock upon the door, and the genial Captain Spooner pushed his head into the room.

"That Dr. Ryder's here," he said. "Should I bring him into you?" and so a minute later the young medico appeared.

In reply to the questions put to him, he explained at once that he really knew nothing about the Mr. Howard whom he had introduced into the club the previous day, and had only given him some golf at the suggestion of his uncle, the Reverend Julian James, the Rector of St. Jude's.

"As a matter of fact," he said, "I had never seen him until the day before yesterday, when my uncle brought him round to my house. Then yesterday I took him for that round of golf, and, by chance, saw him again for a few minutes, later in the evening."

Dr Ryder laughed. "Well, I was called in to save him from a police constable who appeared most anxious to take him up," and then the doctor related all that had happened about Mr. Howard coming into his surgery.

"And have you by any chance lost anything?" asked Larose with a grim smile when the doctor had almost finished his tale, "any opium tablets, for instance?"

"Not that I know of," replied the doctor, "but I can soon find that out, for I keep my hypodermic tablets in my bag, and it's outside in my car. I'll go and get it."

"One moment, please," said Larose, as the doctor was about to leave the room. "Give us your description of this Mr. Howard."

"About five feet ten, middle-aged, stout, with a bit of a paunch," rattled off the doctor, "hair black and rather long, small naval beard, heavy features, dark complexioned and wore dark glasses, prominent upper lip and front teeth." He frowned. "Didn't look an active man and very much surprised me how well he could golf. He made some really splendid shots and beat me four up and three to play," and then upon a nod from Larose, he went out to fetch his bag.

"Does that answer to the description of this Herr Mitter, Mr. Larose?" asked Carter quickly.

"Not a bit," scowled Larose instantly, "but it does answer to the description of one of the disguises that fine gentleman sometimes assumes."

Dr. Ryder was back again, with his bag. "Now I have three tubes of morphia tabs here," he said, "two unopened ones and one that has had a few tabs taken out," but less than a minute's search showed him that there were now only two tubes there.

"Well, that's awful!" he exclaimed very aghast at the discovery. "Then the man is a drug fiend!"

Larose made no attempt at any explanation but, looking at his watch, asked quickly. "Now where does your uncle live?"

"Next door," replied the doctor, and Larose without any comment, gave a low whistle.

"Now look here," said Larose to the two detectives and the superintendent the instant they were alone, "we shall have to work like lightning now, for if we don't pick up this Carl Mitter within the next twenty-four hours, I tremble to think what may happen. Don't forget he murdered that sentry at Foulness and if these unfortunate professors don't give up their secret at once, he'll be quite equal to more murder after he's tortured them to get all he wants." He rose up from his chair. "Now I'll go and speak to that clergyman and you see what you can find out at 'The Bull.' Then I'll meet you again at the police station. I've still got a letter to show you, but it will keep until then."

So about three-quarters of an hour later the four were together again in the superintendent's office at the police station.

"Things couldn't be clearer," snapped Larose. "He was staying here in Cambridge three weeks ago for five or six days, and he got to know the old clergyman by asking permission to photograph his church and then he made a donation of £5 to the church funds. The rector then invited him up to a meal and he pumped the old fellow dry about Dr. Fergus. He found out all about him and Professor Carling; how it was rumored they had made some marvellous discoveries together in their laboratory; how they were inseparable and the greatest of friends; how they went golfing together in the early mornings, and always caddied for themselves"—he threw out his hands. "Well, he obtained all the information to make possible, in an easy way, this coup of this morning." He regarded the others enquiringly. "Now did you find out anything in the hotel?"

"Only that he had the most expensive tastes in wine," frowned Carter, "that he was seen by one of the waiters, at a public lecture given by Professor Carling in the Town Hall, a fortnight ago last Tuesday; that the night before last one of the chambermaids going unexpectedly into his bedroom, surprised him poring over some large maps, that he had evidently taken out of a small black attache case that was upon the table, and that he must have been keeping in his suit-case, because she had not set eyes on it until that moment; and one thing more, that last night he went off in a tremendous hurry, after enquiring very loudly of the reception clerk which was the better way to town, through Royston or Saffron Walden"—he nodded—"which of course means, although he started off in their direction, that his ultimate destination was in quite a different place."

"Well, I'll now read you this letter," said Larose, taking an envelope out of his packet-book, "and it makes things look not nearly so hopeless as they may seem. It's the one I found in Mitter's jacket, two nights ago, and it explains the hurried visit to me of that man when I was in Moon Buildings. There's no date on it, but it was evidently written the day before his call and put in the letter box then, when Dr. Smith was not in his rooms. Listen most carefully," and he at once proceeded to read very slowly.

"Just a line in case I don't have time to look in to-morrow. I shall be seeing the two beauties off in the morning. I have picked them very carefully, and they are just what you wanted and will not jib at anything you want them to do. I've warned them both, on the quiet, not to trust each other, so that there are not likely to be any confidences between them. They will find everything O.K., except, of course, that the place is hellish damp, as might have been expected. There's just enough furniture that they will want, and I managed to get it down during the Sunday night. No one saw me come or leave, for I did not go through the village. I did not drive in through the gates, for the road there looks as if it would be always muddy, and any car wheels show up too plainly. There are no blinds to the front rooms, and so they are not going to have any lights there. Also, I told them on no account to have any fire. They'll have to make do with the oil heater. I'll see they don't take down a drop of drink, and they will be close to the house every hour of the twenty-four. But you need not worry there, for they'll find plenty to amuse them within ten yards of the back door. The big one, Dukes you'll call him, lived as a boy at Staines."

He looked up. "That's all, no address, no signature, ordinary envelope, and paper torn off a pad." He handed the letter across to the others, and the three heads bent close together, as they scanned through it for themselves.

A short silence followed, and then Larose spoke again. "Now we can start off with the certain knowledge that the doctor and the professor were kidnapped to obtain from them the secret of the composition of that new glass, and that Carl Mitter, of Dunwich Hall, is the prime mover in the kidnapping. Mitter found out in some way that Dr. Fergus was directing the manufacture of the glass upon Foulness, and coming down here to make further enquiries about him, learnt of his close association with Professor Carling. Therefore he guessed that the professor would be in the secret as well, and waited until the doctor came back, so that he could get them both at one and the same time."

"Of course, he realised it was better to seize them both," commented Stone, "for then he could be certain that what he got out of them was the truth. There's no doubt he will put pressure upon them separately."

Larose nodded. "Now first," he went on, "we are all of opinion that he left here so hurriedly last night to go and fetch these men. He wouldn't want more than two helpers to deal with Dr. Fergus, and the professor, and the professor particularly so, taking them by surprise, for Professor Carling is a man of very small physique, and Dr. Fergus—I know him—does not look the kind of chap to be able to put up much of a fight."

"It's exactly as Mr. Larose puts it," he said. "The professor is only about five feet two, and neither of them are muscular men. Besides, if he was only going to have two to help him, that would explain in some way the risks he took to keep Mr. Luscombe and Captain Spooner out of the way."

"Then between ten o'clock last night and eight-thirty this morning," went on Larose briskly, "he was able to go to that house referred to in this letter, pick up his confederates, and, returning here to Cambridge, be ready waiting by that seventh green." He looked at each of his companions in turn and asked sharply—"Now in which direction does that house lie?"

"North or north-east," said Stone promptly, "for if that fellow who came to see Dr. Smith in such a hurry that foggy morning had run all the way from some station, as he told you he had done, then the only railway station he could have run from would be one near to Moon Buildings and therefore it was either Fenchurch street, Broad street, or Liverpool street, and preferably I'd select Liverpool street, because 'seeing anyone off' implies starting them upon a long journey, and not a short one as would be the case if they had taken train from Fenchurch or Broad streets. Besides"—and he pointed with a short and podgy finger to the letter lying upon the table—"he, apparently, takes some pride in stating that he managed to get the furniture down during the Sunday night, suggesting thereby that he was something of a smart chap to have travelled quite a good number of miles very expeditiously." He nodded emphatically. "Yes, I vote for Norfolk or Suffolk."

"And I agree there," commented Larose instantly, "for he probably knows both those counties like the palm of his hand. He's an ardent motorist, and is always driving about for shooting, fishing, and attending coursing meetings. Now the next question is, how far away is the place he's taken them to?"

"Wouldn't it be near," suggested Carter tentatively, "because if the kidnapping had been discovered soon, he'd have known a call would be broadcast instantly to look out for his car?"

The superintendent laughed. "If a call had been sent out," he said, "to anyone acquainted with the by-roads of Norfolk or Suffolk it would have been child's play to drive through the cordon that had been thrown round. Why, you could drive from here right across to the North Sea without touching a village or town, if you knew the country well."

"And another thing," said Larose. "If the house he is taking them to lies close near, why should he have been poring over large maps the night before last, as that chambermaid said she saw him doing?" He shook his head. "No, he was refreshing his memory so that he would be sure of his route in an emergency."

A short silence followed, and then Larose went on. "Now, we've got to find a house that has been taken within the last three weeks, and it will certainly be a largish one, and standing in its own grounds, for it was isolated enough from other habitations to make the writer of that letter confident no one heard or saw him bring that furniture in. Also, it must be of good size, because it has two ways in which you can drive up to it, for he mentions that it is not wise to make use of one of them. Well, we want a large house, away from a village, and——"

"Standing on the bank of a river," broke in Stone, who was now holding the letter in his hand. He looked round at the others. "You see, this man writes they'll have plenty to keep them amused within ten yards of the back door. The big one lived as a boy at Staines. Well, can you think of anything else but fishing that would give them plenty of amusement for an unlimited period of time, within ten yards of a back door? Besides he goes out of his way to mention that one of them once lived at Staines." The stout detective's eyes twinkled. "I've got an aunt who lives at Staines, and in my time I've lifted many a juicy trout out of the good old Thames there."

"Splendid!" exclaimed Larose with enthusiasm. "I tried to puzzle that out, but was beaten every time." He pointed to the letter. "Now there's another thing that will help us then. Undoubtedly they've got a telephone installed in the house, for otherwise why should he mention that the two men would be close near the house during every hour of the twenty-four? That must mean that he was assuring this Dr. Smith that the telephone would certainly be heard if the bell rang. Well, if this house has been unoccupied for some time, which of course it has been, because, as he writes, it is 'hellish damp as might be expected,' then undoubtedly again the telephone was disconnected when it was empty. So it has been put in service within the last three weeks for the new incoming tenant."

"Very plausible," nodded Carter with a smile, "but how can we be certain that Herr Mitter himself hasn't owned the house for a long time?"

Larose shook his head. "It isn't likely," he said, "and besides, one remark in that letter makes it highly improbable. The writer gives Mitter some advice about the house that, if it were Mitter's own property, Mitter would most assuredly have known already. He tells him that the road in front of the drive looks as if it were always muddy, and he would, surely, hardly write that if it were Mitter's own place."

"Quite right!" agreed Stone sharply. "Then we can get to business at once and look for a lonely house that has just been taken, has had the telephone installed or connected up, and is situated upon the bank of a river."

"Big job as far as the river is concerned," remarked the Superintendent, gloomily, "if we are going to assume that it is somewhere in Norfolk or Suffolk." He indicated a big map open upon the table. "Look at the rivers there. The Great Ouse, 160 miles long, opening into the Wash; the Yare, 60 miles, running into the North Sea at Yarmouth, and the Welland and the Nen, both about 80, and opening, too, into the Wash. Besides, there are scores of lakes, big and small, in both counties."

"Never mind, we'll tap all the telephone exchanges first," said Stone confidently, "and find where any telephone has been connected for a new subscriber. Then well get down to a house that is right up close to some water."

"But one thing," said Larose, as they all rose up to terminate the conference, "the Intelligence people are adamant that no general publicity must be made, for if Mitter gets wind we are closing on him it is almost a certainty he'll burn his boats behind him and murder those two poor men, out of hand. We are so disturbed there, that not knowing Mitter's resources and where he's placed his spies, we are not even venturing to draw a cordon round Dunwich Hall, to intercept him when he returns there."

"That's bad!" grunted Carter, "for he might be caught red-handed, with the formula upon him."

"We can't help it," said Larose, "for again, if he knew we were waiting for him, he'd get the formula put in some place of safety or sent off in some way before he returned home. If he does succeed in getting hold of the formula, our only chance of taking it from him is to catch him, unsuspecting any danger, directly he's set foot again in Dunwich. We are to receive instant word from the butler, directly the supposed gardener returns."

And then followed many hours of dreadful anxiety and distress for Larose and the two inspectors and the myriad helpers who were working under them. Fully aware how desperate was the need for haste, they none of them took off their clothes, they had their sleep in snatches and their meals were nearly always eaten standing up.

They had started off very hopefully, but had soon come to realise the magnitude of the task before them. The Michaelmas quarter-day had but recently passed and there had been such a large number of new tenants taking possession of houses and connections and reconnections of telephones.

The houses too that in one way or another suggested the particular one they were wanting were much greater in number than they had expected, and although the police of three counties were hot upon the trail, the work, because of the very secrecy in which it had to be carried out, was necessarily of a slow nature and occupied a lot of time.

When a cordon was being drawn round any suspected place it had to be done by the best men and with every precaution taken, and as if they were quite certain they were at last in touch with the gang they were after.

Then, too, they were handicapped by the fact, as was learnt afterwards, that the house on Scoulton Mere had been leased privately to Mitter, and not through any agent, and again, by Larose having made an error in the deductions he had drawn from what the man had written in the letter referring to the intensive occupation of the house.

All the writer had really intended to convey was that the two men would never leave the vicinity of the house to go into the village, but would always be ready for instant service, and listening for the approach of any car that would be entering by the back drive, either day or night.

Larose and the two inspectors who were directing all the investigations kept in touch with one another by almost hourly rings upon the 'phone, so that in the event of a more than usually likely place coming under the notice of any one of them, they could gather together with the utmost speed.

But disappointment succeeded disappointment, and Larose was in the very depths of despondency when, just as dusk was falling upon the third day, he had repaired to a hotel in the little town of Wroxham, upon the Norfolk Broads, for some much needed refreshment, an urgent call came through upon the 'phone from Stone.

The inspector was at Swaffham, he explained, and there was a supposed unoccupied house upon the bank of Scoulton Mere that they were going to examine immediately.

It was not one of these down upon the list as having had the telephone reconnected, and no one in the neighborhood was aware that it had been let or sold, and that any one was coming into residence there, and no signs at all had been noted in the village of any arrivals.

However, the village constable had had it in his mind, as a likely house, ever since the call for a residence of that description had been broadcast, and had accordingly been keeping his eye upon it, but following the general instructions issued, he had made no open move to approach up closely.

He had cycled by the front gates the previous day and noticed nothing suspicious, but that very afternoon, indeed not an hour ago, he had come suddenly to the conclusion that it now was occupied and thereupon had immediately communicated with Norwich.

"All right," exclaimed Larose instantly, when he had heard what Stone had to say. "I'll come at once. Where shall I find you?"

"We'll wait for you upon the Higham road," replied Stone, "and be as quick as you can. We shall be just where you have to turn off to get to the mere. The house will then be only about three hundred yards away."

And so a little over half an hour later the two cars met. Stone had three plainclothes men with him, as well as the village constable, and Larose was accompanied by the three men who had been helping him.

The village policeman turned out to be a very intelligent young fellow, and for the benefit of Larose quickly repeated his tale.

He had cycled by the house only twice; the first time, the previous day, and then again not a quarter of an hour before he had phoned up Norwich.

Upon the second occasion, just as he was passing the gates, he had seen a flock of wood pigeons upon the roof, and while he was looking at them, to his great suspicion, they had all suddenly whirled themselves into the air with every appearance of alarm, and he was sure they had been frightened by someone round at the back of the house. Then a few yards out of sight of the windows, he had stopped behind some trees, and sniffing hard, was positive he had caught a whiff of burning paraffin.

"That's good enough," nodded Larose, "and you are a sharp chap. Come on; we musn't waste a moment."

It was now quite dark, except for the dim light of the stars, and pushing their way with difficulty through a thick hedge, the party proceeded to surround the house very cautiously. They spread themselves out just far enough from one another so that each one was just within sight of his neighbor. Stone and Larose went round to the back door.

"Have your gun ready," whispered Larose, "for if Mitter's here, he won't hesitate to shoot."

Larose tried the handle of the door and it yielded to his touch. A great misgiving seized him and with a muttered imprecation he flashed his torch.

They saw a long passage before them, with doors opening on either side. Wasting no time now and with no hesitation, they ran quickly up, pushing open the doors and flashing their torches into each room as they passed.

The first two rooms were empty, but in the third they saw the figure of a man stretched out upon the bed. Larose sprang forward and then as he took in with a lightning glance the pose of the recumbent figure, and that he was bound hand and foot, gave vent to a cry of horrified dismay.

Then to his great thankfulness the doctor, aroused by their entry, opened his eyes and stared round.

"Who are you?" he asked feebly. A shudder convulsed him and he went on brokenly. "You are not going to hurt me any more!"

"No, no," exclaimed Larose quickly, "we're police and you're quite safe now," and with shaking hands he proceeded to untie his bonds.

"Here, drink this," said Stone and he forced some brandy from a pocket flask between the doctor's lips.

"I've had a bad time," whispered the doctor faintly, when he had imbibed some of the spirit. "There's been a devil here. Look at my foot."

With a sickening feeling at his stomach. Larose lifted the coverlet at the bottom of the bed, but then after a quick glance at the bare foot exposed, dropped it hurriedly again.

"Somewhere in the house," said the doctor. He shuddered a second time. "I heard him cry out, twice."

The men outside were called in and the other rooms quickly gone through, but there was no one else in the house besides Professor Carling and he was sleeping heavily in a room just across the passage.

Larose tried to rouse him, but without any success, and lifting up one of his eyelids, saw that the pupil was like a pin-point. As with the doctor, one of his feet was bare and upon the sole were four dreadful burns.

Larose swallowed hard several times and swore a deep oath. Then he hurried back to the doctor. Stone had lit a lamp that he had found there upon the table and was just starting to bathe the doctor's forehead with cold water.

"The other chaps been doped," whispered Larose. "Opium, it looks like to me, but he doesn't seem to have been given a fatal dose, as there are no signs of collapse. He's not sweating at all and his pulse is steady, although very feeble." He shook his head. "But I can't wake him and goodness only knows when he'll come to. Now it's vital we should learn how long those devils have been gone, and I'll have to question the doctor, although it seems very cruel."

Stone nodded. "Well, make it snappy," he said, "for he doesn't look as if he'd stand much. He says he's had no food since they brought him here."

Larose bent over the doctor and addressed him by name, and the latter opened his eyes again and smiled. "I remember you," he whispered. "You came to Foulness, didn't you? I recognise you by your voice. You are that Mr. X."

"Yes," smiled back Larose. "I had dinner with you all, that night." He patted his hand gently. "Now, look here, doctor. You'll be quite all right now and you'll soon be back home." He spoke reassuringly. "Those burns are nothing, and will soon heal. It's only shock and weakness you're suffering from now."

The doctors eyes filled with tears. "But he made me tell a secret I ought to have died before I told," he groaned. He suddenly raised himself up and spoke fiercely. "Quick! Go after him and get him put in prison. It may not be too late yet to shut his mouth. He can't have been gone very long."

Larose pressed him gently back upon the bed. "Now, don't you anger yourself," he said soothingly. "Lie quiet and keep every little bit of strength you've got to help us." He spoke with complete confidence. "I'll get that fellow in a few hours, and before he's had time to do any harm. I know who he is and where he lives." He bent down closely. "Now tell me how long he's been gone."

But his emotion had exhausted the doctor, and he had closed his eyes again. "I don't know," he faltered wearily. "I can't think or remember anything, and I lost all idea of time. I seem to have been lying here for months and months."

"Nonsense!" exclaimed Larose sharply. "It was only the day before yesterday that they brought you to this house. Come, come, be brave and pull yourself together." He spoke in very matter-of-fact tones. "Now, there were three of them, weren't there?"

"Yes, three of them," replied the doctor, opening his eyes and his face brightening a little. "I can remember that." His voice grew stronger. "Yes. They came up to us when we were on the golf course, and one of them knocked me down." He put his hand up to his face. "Oh, my jaw is still so dreadfully sore."

"Of course it is," said Larose sympathetically, "and anyone's would be." He laughed. "See, your memory's all coming back."

"Yes, and then I didn't wake up for a long while," went on the doctor slowly, "and then one of them began asking me questions, and I wouldn't tell him anything." His voice began to choke. "He wanted, he wanted——"

"The secret of the new glass you're making, of course," said Larose cheerfully. "And naturally you didn't want to tell him. Then he hurt you to make you speak, and, like a sensible chap, you realised there was no help for it, and so you told him." He laughed again. "Why, anyone would have done it. I am sure I should."

"But I didn't give in at once," said the doctor tearfully. "He had to burn me twice."

"And very plucky of you," said Larose, "to hang out for so long." He nodded. "Then, having got what he wanted, he, of course, went off at once with the other men. Now tell me, how long ago do you think that was?"

"Oh! I can't remember," replied the doctor faintly. "I have no idea at all. It might have been yesterday; it might have been ever so long ago."

"But you became thirsty after he had hurt you, didn't you?" suggested Larose. "You know, people generally do, after pain."

"Yes, yes, I did," said the doctor at once, "and he gave me a drink of water. He was quite kind to me then, and held up my head so that I could swallow it."

"But some of it was spilt," went on Larose, "and that's how your collar became wet. I've just noticed it. Feel, it's still damp down this side."

"Then of course," laughed Larose, "they can't have been gone very long, for only a little bit of your collar is wet and it would have been quite dry now if you had had your drink hours and hours ago."

"Yes, I remember now," said the doctor, "seeing a streak of lamp-light above that door, some time after he had left me and I couldn't have seen it if it had been daylight outside." His voice rose to a wail. "No, they can't have been long. Oh! do be quick and go after them! He got the secret of the formula out of Professor Carling, first, and then he compared mine with his. He said he would have killed us both if they hadn't been the same. He threatened me with a pistol." His eyes glared wildly. "Oh! say my friend isn't dead!"

"No, no," said Larose, shaking his head. "He's only been drugged with opium and he's quite all right."

"That's what the man said he was going to do," cried the doctor, "and he told me that when my friend woke up he would be able to cut these cords for me and we could both get away."

"He was rough and coarse," replied the doctor, his anger now seeming to give him strength, "and he had a stubby beard. His front teeth were prominent and very stained and on one side there were several missing. I never saw his eyes, for he had big, dark glasses on all the time. He always had his hat on, too, and it was pulled down low upon his forehead, and he always wore gloves, so I didn't see his hands."

The doctor sank back upon the bed. "But please don't ask any more questions," he sighed. "I've told you all I know and I'm very tired."

Larose rose briskly to his feet. "Well, don't you worry any more," he said. "As I say. I know where the fellow lives and as he won't be expecting us, I'll most likely get that formula back before the night's out. Good-bye for a little while. This gentleman here is Inspector Stone from Scotland Yard, and he'll see you both out of your troubles now. Your bad times are over."

"There's a phone here," said Stone when they got out in the passage, "but it's not working, so I've sent the constable into the village to ring for an ambulance from Norwich. These chaps will be best in hospital."

They made a quick survey of the big kitchen which the men had evidently used as living-room as well.

"We'll look out for finger-marks here," growled Stone, "but we'll certainly not find any of the party we most want, if he were wearing gloves all the time, as that poor chap says. Gosh! Look at those empty tins! See, only hard biscuits! They've had no bread! They've been living here like animals all the time!"

But Larose had darted to the scullery sink. "Look at that soap," he said, breathing hard. "It's almost wet. No, they've not been gone long, and I'll be off at once."

"But you just wait a minute, my friend," said Stone sharply. He eyed Larose curiously. "The formula's gone right enough and it seems to me you've a devilish poor chance of preventing it getting out of the country. Now what exactly are you going to do?"

"I'm not so sure that I won't get it back," snapped Larose. "He'll be thinking he's quite safe, and as there is nothing to point to him in the matter, he won't be in any desperate hurry. So if I know anything of my gentleman and his habits and his love of comfort, I reckon he will go home and have a hot bath, and a good night's rest." He waved his arm round. "As you say, look how he's been pigging it here! No bed to sleep on, and, of course, like us he's not taken off his clothes for two nights!" He laughed. "And he'll be wanting a good dinner, too, and a bottle of that wine he gave me. I know him!"

But the stout inspector looked very grave. "But, see here, son," he said, raising one fat forefinger warningly, "unless you knock him out and score a straight-out bull's-eye by finding the paper on which he's written down the formula, actually upon him—remember, you've got deuced little to go on. The doctor here's not going to identify him, and, from what you tell me his ordinary appearance is, none of those people in Cambridge are going to, either." He shrugged his shoulders. "And with the alibi you tell me he can put up—and there again—remember, it's mostly conjecture on your part, and you may be able to prove nothing"—he threw out his hands—"why what jury would convict?"

"Jury!" exclaimed Larose scornfully. "He's going to get no jury!" He gritted his teeth together. "Go and look at those burns on the professor's feet. He held out longer than the doctor did, and the iron was put on four times. The flesh in one place is burnt to the bone." He looked round to make sure they were not being overheard, and lowered his voice to a whisper. "By hook or by crook, Charlie, that man's going to meet trouble tonight."

Stone grinned uneasily. "Then good luck to you, my boy, and reckon upon a farewell visit from me the night before you come to take the drop." He spoke in matter-of-fact tones. "Well, after these poor devils have been taken to hospital, I'm going to ring up the Yard. My job's finished here, and I must get further instructions from headquarters."

Larose was adjusting his motor gauntlets. "Well, if they decide you are to follow me, when you come to a small plantation on the right, about a mile beyond Westleton village, stop and see if I've left any message for you. My men will be waiting there, as I shall go up to Dunwich Hall, alone."

Larose shook his head. "Not if I can help it. I'll tell whatever tale there is to tell—myself."

CHAPTER XIV
THE BURIAL OF THE DEAD

NOW it was by a bare half-hour, only, that Mitter had left the house upon the mere before the cordon had been drawn round it.

He had gone off by another by-road, and turning into the main Norwich road, much higher up, his car had actually passed that of Larose just as the last-mentioned was emerging from the environs of the city itself.

Having no idea that his identity as the Mr. Howard of the Bull Hotel had been discovered, and that two days previously every police constable within a radius of 150 miles had been on the lookout for a man of that description, in a grey Jehu car, with number plates C.L.3964, he left Scoulton Mere in the disguise he had assumed in Cambridge, except that for comfort's sake he had now discarded the small naval beard.

He was of opinion that he was perfectly safe, but had he only known it, his immunity from discovery and arrest, during the succeeding few hours, was almost miraculous. He passed, unhindered, constable after constable whose minds, forty-eight hours previously, had been obsessed with the thought of a stout, dark man in a car like his.

He had no intention of returning straight to Dunwich, but was intending, first, to drop his confederates in different places, with the idea in his mind that they should have no opportunity of talking over all that had happened. He was fearful that in their relief at having finished with the whole business, and with their very substantial pay in their pockets, they might be inclined to open out a little to each other, and discuss what had taken place.

So he drove openly into Norwich and landed Dukes at the railway station there, waiting even, to see him off in the London bound train, so that by no chance should a drink or two in the city unloosen his tongue to any companions he might pick up there.

Then, with the same confidence, he carried Fletcher to Great Yarmouth and saw him off in a train, too. Then he purchased the morning and evening papers both of that day and the preceding one, and betaking himself to the refreshment buffet of the railway station, proceeded to scan through their contents.

He was, however, not much surprised to find no reference to the missing men, for he had been rather expecting the authorities would not have deemed it advisable to broadcast anything of their disappearance in the press, lest the public, generally, should have become too curious as to the exact significance of their kidnapping.

He turned also to the obituary column and those reporting fatalities and accidents, and frowned when he found nothing of interest to him there.

Then he heaved a deep sigh of relief that the difficult matter of obtaining the formula was over and done with, and returning at length to his car, which he had parked outside the railway station, he drove leisurely away in the direction of Dunwich.

As he drove along his thoughts were certainly very exultant ones. He had possessed himself of the greatest secret that, surely, any secret service agent had ever obtained, and one that would be of incalculable value to his country. He was quite certain that he had obtained the correct formula from his victims, for the two that they had given him tallied exactly.

During the past few weeks he had made an intensive study of the chemical composition of various classes and he marvelled now at the very slight variation in the combination of the metallic oxides used, as shown by the formulas he had written down, that could give to this new glass a refractive index differing so very little to that of air.

For safety's sake he had already committed the formula to memory, and it was indelibly impressed upon his mind.

There way one fly in the ointment, however, and it was a fly of rather large dimensions, for he could not help feeling very disturbed whenever he thought of Larose, and he was keenly disappointed that no accident, as he so confidently had hoped, had apparently happened to him.

For upwards of a year, he ruminated, he had been aware that he himself was being watched by the counter-espionage people in Whitehall, and knowing now that Larose was working for them, as evidenced by the latter having been closetted for three hours that night in Room 13, it had become the obsession of his, Mitter's mind, that it was to Larose he owed all that had taken place that morning in Moon Buildings, when someone had gained an entrance into the consulting room and acted the part of Dr. Smith.

The very daring and audacity of it, he told himself, was just such a thing as Larose would do. The prim and orthodox Intelligence Department would have never thought of it. They would not have had the imagination, and if they had, they would not have dared to carry it through.

But Larose would dare anything, and it was well known that, if need arose, he could be as unlawful and unscrupulous in his acts as the most hardened criminal who had ever stepped into the dock. And he, Mitter, looking back, thought he could see clearly how it had all come about that Larose had taken up secret service work against him.

Up to that day of the shooting party at Carmel Abbey, he and Larose had been good friends. He had admired him and thought him excellent company, and had never wearied of the tales he had told of his detective days.

But that afternoon, Arthur Grant, Colonel Bevan, and Sir Herbert Carnaby had unexpectedly become aware that Larose knew him, and no doubt that night had made a confidant of the ex-detective, and there and then enlisted him in their service.

Of course, Larose had been thrilled with the idea, for the passion of his life was hunting people down, and it was well-known that, with all his altered circumstances, he had never shaken off his love of trailing anyone who was working against the law.

But then Mitter threw off his gloomy thoughts and smiled complacently to himself. Well, he had bested them all this time, for sure! He had proved himself as great a master as Larose, and had smitten the famous British Secret Service hip and thigh.

And there was no likelihood, either, he told himself, that Larose or anyone else could bring home the kidnapping of the professors to him.

He had covered his trails everywhere, and even if the gravest suspicions came to be held that it was his work, no one would ever be able to prove anything.

He was sure his disguises had been so good that no one would possibly be able to identify him; his helpers had melted back into the underworld, and would not know him again if they saw him, and his good fortune had held all along.

He speeded up sharply, thinking with pleasurable anticipation of the comforts of Dunwich Hall that were awaiting him; and then, all suddenly, the good fortune that he had been so congratulating himself upon began to peter out.

To begin with, in passing through the main street of Lowestoft, he collided with a man upon a bicycle, and although the man appeared to be only very slightly hurt, and was quite satisfied with the two pounds given in compensation for his injuries, a crowd gathered, and after some questioning of Mitter by a young policeman, the latter asked to see Mitter's driving licence.

Then, as Mitter had already given a false name and address, and as his number-plates were false as well, it was not surprising he was unable to produce it.

Further, although he promised to forward it for inspection, within the regulation forty-eight hours, the policeman was not satisfied, and with pencil and notebook in hand, stood regarding Mitter very doubtfully. It was three days since Mitter had shaved, and his general unkempt appearance made the young constable suspicious that the car might have been stolen.

"I've been duck-shooting on the Fens," explained Mitter, casually, noting and understanding the policeman's intent regard, and then he took out a gold cigarette case, and helped himself to a cigarette. "If you've any doubt about my possessing a license," he went on, "ring up the Chief Constable of Norfolk, Sir George Blamey. He's a friend of mine."

Whereupon the youthful guardian of the law, impressed by the cigarette case and the mention of the Chief Constable's name, at once thought better of asking Mitter to drive round to the police station with him and interview the inspector. Instead, with a gesture of great magnanimity, he closed his notebook with a snap and waved for Mitter to drive on.

A few hours later, however, when Police Constable Peter Jones came to make out his report of the day's happenings, he became all suddenly a very sick young man, for it had flashed like a stroke of lightning into his mind that a bare forty-eight hours previously an urgent call had been broadcast to look out for a stout, dark man, who would be driving a grey Jehu car, and who might, or might not, be accompanied by two other men.

Thereupon, with a word he did not often use, for Policeman Jones had been brought up a good young man, he tore a whole page out of his notebook and consigned it to the fire.

In the meantime Mitter had made all haste to get out of the town, and the moment he was clear of its environs he turned off the main road and began to zigzag among the small and generally little used lanes lying adjacent to the coast.

He was fearful that the young policeman might after all have rung up the Chief Constable of Norwich, in which case he knew that gentleman would have at once repudiated all knowledge of any individual of the name he, Mitter, had given.

"A close thing!" he murmured. "Touch and go all the time! If only he had looked to see if there was any gun in the car!" He wiped over a rather clammy forehead. "It would have been a dreadful piece of luck if the last card had given them the odd trick!"

But he was not free of all his troubles yet, for he had not been driving ten minutes when he had a blow-out, and, added to that, he found that his spare tyre was flat. He had trouble then with the valve of the inner tube, and altogether he was delayed a full three quarters of an hour.

However, at last he was able to proceed again, and then, when within two miles of Dunwich, his movements to anyone who had been watching would have seemed very peculiar.

He switched off his lights, and, driving very slowly, turned off into a narrow lane, at right angles to the one he had been travelling upon. Then he stopped his engine altogether, and alighting from the car, disappeared up the lane. He was gone about five minutes, and then returning at a quick run, he jumped into the car and drove it very quietly in the direction from which he had just returned.

Ten minutes later, quite a different-looking man appeared from the entrance of another lane, about a quarter of a mile away. The man was riding a bicycle without any light, and upon his head was a tattered hat, pulled low down. His clothes were worn and soiled, and evidently his walk in life was a lowly one.

He pedalled quickly along under the bright moonlight that was flooding the countryside.

AS Larose, upon driving away from the house upon the mere, with open throttle and with foot pressed hard upon the accelerator, pushed his engine to its utmost revolutions, there was no one sitting in the car who was not filled with troubled thoughts.

As the car swayed and bumped and rocked, and as it shot like a bullet down the narrow lanes, the three men who were accompanying Larose were not disinclined to be of the opinion that each moment might turn out to be their last, and that whatsoever dangers might lie at the end of the journey, they certainly could not prove more serious than those to which they were then being exposed.

It was true that there was a full and bright moon, and that their association during the past two days with the man who was now driving the car had given them every confidence in his complete mastery of it, still—a rate of fifty, sixty, and even seventy miles an hour could never be without its hazards along the narrow by-roads they were traversing at such a pace.

But with Larose himself the trouble of his thoughts was of quite a different nature.

When he had started upon his journey from the Mere, his one idea had been to get in touch with Mitter with the least possible delay, obtain the paper upon which he would have undoubtedly written down the formula he had wrung by torture from his victims, and then—much harder still—find some occasion of so dealing with him, that Mitter would get no chance of passing on the secret to anyone else, by word of mouth.

But now the dreadful thought had come to him that, after all, Mitter might not be the man he actually wanted, and that in laying hands on him, he might grasp only the shadow, and the substance would be evading him.

For now he came to review all the evidence dispassionately, he saw that he could not be certain it had been Mitter who had been either the Mr. Howard of Cambridge or the torturer in the house upon the mere.

For was it not possible, he asked himself, that it might have been the other man, the supposed ill-kempt gardener, Sullivan, who was so much like Mitter, who had carried out the kidnapping, and indeed, who all along had been the one he had trailed from Foulness to Moon Buildings?

The similarity between the two men, as he had seen with his own eyes, was a profoundly striking one, and there could be no doubt they were close blood relations—it might even be that they were brothers—and capable and enterprising as Mitter undoubtedly was, it might be that the same or even greater powers of intellect were possessed by the other man and that his was the master mind.

It was certainly Mitter who had been watched by the Secret Service for a year and more, but undoubtedly aware that he was under their suspicion, as evidenced that he knew Dempster had been writing letters to the Intelligence Department as to what was going on at Dunwich Hall, he had yet sat tight, and carried on as if he had no fear of any grave consequences if things did come to a climax and there was a showdown of all the cards.

It looked as if Mitter were quite confident that if the authorities did strike at him, they would get nothing for their pains!

Then as Stone had just warned him, Larose, what evidence had he against either of these men that would satisfy a jury if they were brought to trial?

Very little, or practically none, for everyone who had been brought in contact with them on their varying disguises had been chary of recognising them and had had to be prompted in picking them out, and then had only 'thought' there was some kind of likeness! Yes, there was no sure ground anywhere.

Larose shook his head vexatiously. "But I know it has all along been one or other of them," he snarled. "I need no convincing, and whoever is the torturer or the murderer, they are both damnable and dangerous spies, and to be too squeamish now in dealing with them would be sheer cowardice on my part. Of one thing I am quite certain. It was Mitter who tried to poison me, and on that account, alone, there must be some settling up."

Then he began to think what exactly he was going to do when he reached Dunwich Hall and his perplexity was at once as great as ever.

It was one thing to have told Stone he was going to deal with Mitter out of hand, but it was quite another when he began to consider how exactly he was going to do it.

It was impossible to go boldly up to the Hall and threaten Mitter with immediate death if he did not at once deliver over the formula. Mitter would call his bluff instantly, for the son of Mangans, the spy, was no fool and would know quite well there would be no pistolling with witnesses about. Besides, there might be no formula to deliver up, for if Mitter were, indeed, the one who had obtained it, he might have committed it to memory and burnt the paper, before he had even come away from the house upon the mere.

And yet again, whichever of the two men had returned to Dunwich that night, he would certainly have instantly passed on the secret to the other, and therefore to deal with only one man was as profitless as dealing with neither.

Larose heaved as deep a sigh as he had ever heaved in all his life—and then suddenly a ray or hope flashed in to his mind, the hope of the gambler who is for ever expecting fortune from yet another throw of the dice.

Instantly then, he quietened down to the calmness of one adding up a sum, and proceeded to reason very slowly.

The man had had barely an hour's start of him! He could be almost certain there, for surely the wretch would not have ventured to leave the house until night had fallen. Then he had seen that piece of soap had not been thoroughly dry, and, then again, the doctor's collar had been wetter than it would have been if he had been given that drink of water a good time before.

Then was it likely the car would have been stopped by some policeman who remembered that a broadcast had gone out, two days before, for a grey Jehu driven by a stout, dark man, wearing glasses?

Larose did not think for long there. No, he was afraid not, for in arranging the broadcast that was to be sent out, he had trained it, he realised now, as referring rather to a car that would be found upon the roads that same day. Unhappily, at the time, he had not taken into consideration the car going into hiding for forty-eight hours and then re-appearing to make another get-away. Besides, the kidnapper might no longer have the appearance of a stout, dark man, and grey Jehus were as plentiful as blackberries.

Then next—would the man have gone straight home?—and at once Larose shook his head emphatically. No, certainly not! He would never have put himself into the power of his two low class confederates, by letting them become aware, either, who he was or where he lived. The whole suggestion of the letter put into Dr. Smith's letter-box was that Mitter had little, if any, knowledge of the personalities of the men who were going to help him, for had not the writer assured Mitter they would be just the sort of men needed, and would give no trouble in the carrying out any job that was entrusted to them?

Well, if Mitter was not then going to let them know where he lived, it was quite feasible he would not let them hazard its direction, either. So he would not get rid of them, going back in a bee-line for Dunwich, and it was hardly likely he would drop them at a small country railway station, where their presence would be noted. Therefore, considering the locality of Scoulton Mere, it was almost certain it was to Norwich he had taken them, and that being so, it could be guessed he would have purchased the daily newspapers there, and scanned through them to see what was being broadcast about the missing men. All that would have taken up time, minutes only, perhaps, but the minutes would all mount up.

Then, too, and what heartened Larose more than anything, not only would Mitter have not driven as furiously as he was driving, but also, when Mitter had arrived somewhere in the vicinity of Dunwich he would have had to leave his Jehu in the secret place where he was accustomed to hide it and proceed the rest of the way home, on foot.

They knew from Dempster that the two Hall cars had not left the garage during the last three days, and, therefore, Larose was quite sure that this third car, the Jehu, had been kept handy somewhere and taken out, as it always had been, when Mitter was being under-studied by the gardener, Sullivan. No doubt, unknown to his domestics, save only to the parlormaid, of course, Mitter had some way of leaving the Hall secretly, and no doubt again, in some disguise he was accustomed to pick up the car, unseen, and proceed upon his many mysterious journeys, when he was supposed by all to be so busy painting in his studio.

Arriving at last at the small plantation on the Westleton road, to the great relief of his passengers, Larose slowed down and drove between the trees. Then, bidding the three men wait there and keep an eye out for the coming of Inspector Stone, he set off at a sharp pace across the field to Dunwich Hall.

Reaching the entrance to the grounds, he peered quickly round to see if there was anyone in sight. But the drive and gardens were quite deserted, and so, making his way boldly across the lawn, he turned the corner of the house until he came in full view of the rooms occupied by Mitter. There was only one light showing there, and it was in the studio.

"Now, if I'm right," he whispered, his breath coming quickly in his excitement. "Sullivan won't be in his cottage. One or other of them will be away."

He turned at once in the direction of where the gardener lived, but then not thinking it wise to pass down the gravel path, so brightly lit by the full moon, he edged his way along the other side of the garden, where, if the moonlight were still upon him he would yet be out of the sight of the windows of the house.

He had come to within ten paces of the massive oaken door, let in the great, high wall of the ruined chapel, upon which was perched the broken arch that Mitter, but a few days previously, had pointed out as appearing to have become so dangerous, when close near him he heard a harsh crunching sound as of some heavy object being impeded in its movements by pieces of stone or gravel.

He stopped instantly, and turning his eyes in the direction from which the sounds had come, to his consternation saw the door itself being pushed open very slowly, and directly the opening was wide enough the figure of a man slip through.

Apparently, however, the man did not see him, and very gently, although with some effort, because of the small stones that had become wedged underneath, he closed to the door, and then bent down to slip the large bolt into its socket.

Then Larose took in for the first time that the man was carrying a small, black attache case, and as the latter straightened himself up he saw his face.

"Good God!" he gasped, "it's the gardener!" His heart beat furiously. "He was the torturer, then, and that is the black attache case they saw him with in Cambridge," and his hand slipped back like lightning to the little automatic in his hip pocket.

But the man was still unaware of the presence of Larose and tilting a battered hat from off his forehead, he turned his eyes upwards towards the broken arch. Then, in the same attitude that he had seen Mitter assume once before, Larose saw the gardener now place his ear close to the wall and listen intently.

Larose gasped again. "But it's Mitter, it's Mitter!" he breathed. "Then it is he who has been the arch-criminal all along!" and instantly he proceeded to cover him with his pistol.

Then Mitter looked round. His eyes opened very wide, his jaw sagged and his legs bent at the knees. The moon made everything as bright as day, and he recognised Larose and saw the upraised pistol in the latter's hand.

"Don't move," snapped Larose. "Keep your hands down or I'll shoot you on the instant."

Mitter composed his features to instant calm, and, as motionless as a graven image, stood regarding Larose almost contemptuously and with no trace of fear. His forehead, however was pricked out in little beads of sweat.

Larose wreathed his lips into a pleasant smile. "Herr Mitter, I believe," he remarked gaily, "although certainly not quite so spick and span as I am accustomed to see him." He looked curious. "Been away for a little holiday, eh, while friend Sullivan has been understudying here?"

For one fleeting second Mitter's face twitched ever so slightly, and then it sank into an expressionless mask.

"Just returned from Scoulton Mere, of course," went on Larose, still smiling, "and no doubt you've got the formula in your pocket, or else in that little attache case that the housemaid saw you with in your bedroom at the Bull Hotel?"

Mitter made no attempt to hide his emotion now, and his face puckered up, and his eyes glared like blazing coals.

"Oh! yes," exclaimed Larose, carelessly. "I know you've got the formula! Dr. Fergus happened to mention it when we were examining his burnt foot." He nodded. "You are keen on your work, Herr Mitter, and those four burns you gave Professor Carling must have needed a lot of nerve." He shook his head. "I know I could never have braced myself up to make them."

Mitter made no comment. He was swallowing hard. The perspiration was now dripping from his forehead, and his face, under its dark stain, had taken on a dreadful hue.

Then in one split second Larose dropped his railling tone. "Why don't you reach for your gun?" he snarled. "You have got one, you brute, for you threatened Dr. Fergus with it." He jeered. "Have you lost all your courage at last?"

Mitter spoke for the first time. "No, no," he said, shaking his head, "you don't get me that way, Mr. Larose." He jeered now in his turn. "You'll have to shoot me in cold blood!"

"Ay! in cold blood," retorted Larose, furiously, "as in cold blood you tortured those poor wretches with your burning iron." He nodded grimly. "Yes, I'm going to shoot you, right enough, but I'm just considering whether to only cripple you and then let you be hanged later on."

Mitter made a grimace. "In the forehead, if you please, Mr. Larose," he said very quietly. "You've got everything you want and you can afford to be generous." He made a little shrug with his shoulders. "I have only done my duty, and I found it a horrible business at times."

"Who else has been working for you," asked Larose sharply, "besides that man you call Sullivan, and the girl."

"The girl knows nothing," burst out Mitter with some heat, "and you leave her alone." He smiled in some amusement. "And Sullivan knows nothing, either. He's just been a puppet and that's all."

"You lie there, Herr Mitter," retorted Larose instantly, "for I know that bogus gardener is a kinsman of yours and has been working hand in glove with you all the time." His voice rose in anger. "Good heavens! man, don't you think you can bluff me, for I've been watching you for weeks, now!" His words poured out mercilessly. "I know all about your murder of that sentry on Foulness; I trailed you to Moon Buildings and was Dr. Smith there, that morning; I know you gave me a dose of belladonna and tampered with my car." He jerked his head back in the direction of the Hall. "I got in there the night you were at the Ipswich mayoral banquet and was actually in your bedroom when you came home and asked that girl if she'd got hold of Dempster's letter that day." He spoke tauntingly and very slowly now. "Then from the pocket of your jacket, Herr Mitter, I picked the letter that, later, gave me the whole clue as to where you were hiding the kidnapped men." His eyes gloated. "Oh! how I've beated you—you spy, and the son of a spy!"

And all the time Larose had been speaking, he had been on the watch, and waiting for some movement of the goaded man. He had seen the blind fury welling up into his face, the growing frenzy of his blood-shot eyes, and the quivering of the nostrils he could not keep under control.

Then, suddenly, he saw Mitter's knuckles tighten and a stiffening of his right arm, and when in a lightning throw the attache case came hurtling through the air, and with the spring of a panther Mitter darted forward—there came the sharp crack of the automatic, and Mitter crashed down with a bullet in his heart.

Larose drew in a deep breath, as if he were being suffocated, and glanced apprehensively around in all directions.

But the gardens were everywhere deserted, and lay white and ghostly under the moon.

He sprang over to the dead man and dragged his body close up to the base of the wall, so that it might possibly escape notice, if anyone had heard the shot and came out to see what it meant.

Then with a shudder of repugnance, he unbuttoned the blood-soaked coat and went through the pockets, but all he found of interest was a thick wallet in the left breast one. There was ghastly evidence as to where Mitter had been hit, for the wallet was drenched with blood and pierced with a hole where the bullet had gone through.

With shaking fingers he parted the dead man's lips and saw, as he had expected, that the teeth were artificial. Then he covered the face with the battered hat, and ripping up a length of hessian that had been pegged round to protect some young trees nearby, he spread it over the body from head to feet.

But he had scant time to consider what he would do next, for he heard a door opening somewhere, and so, darting up the path towards the house, he crouched down among a clump of rhododendrons about twenty yards away.

Then he heard the crunch of running feet upon the gravel path, and a few seconds later a man appeared round the corner.

"The other one!" exclaimed Larose, with his heart pumping hard, "and dressed exactly as Mitter dresses! He heard the pistol, and has come out, as I thought someone might!" His breath came with an effort. "But, good God! What will happen if he catches sight of the body?"

The man reached almost to the clump of rhododendrons and then, when not a dozen feet from where Larose was crouching, stopped, and with a frowning and puzzled expression upon his face, stood looking up and down the garden paths.

"Oh, but how like Mitter he is!" murmured Larose. "I could almost believe he were Mitter himself." A grim smile came into his face. "So, so, he's carrying a gun, and it's got a silencer on it, too!" He nodded. "He's no innocent, this fellow!"

A few seconds passed and then, when from the man's attitude it seemed that he was about to give up all further quest and retrace his steps, his frown deepened suddenly, and, lifting up his head, he began to sniff hard.

"He smells the cordite," breathed Larose, "and guesses a pistol has been fired near here!"

Then the man sprang forward and started to run quickly up the path towards the chapel wall.

"He's seen the body," muttered Larose, "and now for trouble! These bushes won't hide me ten seconds, if he begins looking about!"

But, to the great relief of Larose, the man had not apparently caught sight of the body, for, passing it unheeded, he made straight for the big oak door and pulled upon its massive handle.

It was evident he did not notice that the door was now bolted, for as if angered that it did not yield immediately, he gave it a fierce resounding kick and then tugged again at the handle, but much more viciously this time.

The door did not yield the fraction of an inch, but from high above came a crack, then a loud rendering sound, and all in the passing of a second the avalanche was loosened.

In a lightning swoop the broken arch swerved down, and, thirty feet below, stuck like a giant hammer upon the chapel wall. The great wall shook, and quivered, and then, in one tremendous heave, swayed forward and came crashing thunderously to the ground.

Too late, the man by the door had seen his danger and had started to dart back, but a huge stone fell upon him and crushed him to a pulp. Then, quicker than the tongue can tell, the dreadful drama had run its course and the two bodies were lying deep beneath a thousand and more tons of masonry, while high up into the air rose a pall of blinding dust.

So, twice had Death struck that night, on the same spot and with such a little time between.

The dead men had been without scruples, implacable in their hatreds, and merciless as beasts of prey, but surely their tomb, now, was one that an emperor, saint or holy man might envy, for not one stone that covered them was not hallowed by a thousand, thousand prayers, and saturated with the chants and anthems of eight hundred years.

With heaving breast and heart palpitating furiously, Larose had sank down on to the ground. The death of the second man had been all he could have wished for and yet, now that he had seen it happen before his very eyes, he felt sick with horror.

Suddenly then, for the second time that night, he heard a door being opened in the hall and then came loud voices and the sound of scurrying feet.

"The chapel wall's gone!" shouted Dempster, and his wife, just upon his heels, gave a shriek of terror, and clutched at Margaret Advent who was following close after.

Then in an awed and dreadful silence the little group stood waiting until the dust had cleared away, and the full extent of the catastrophe could be seen.

"Lord!" ejaculated Dempster, "it'll take weeks to clear away! There's work here for twenty men."

"But the master won't have it done," cried Mrs. Dempster quaveringly. "These stones are holy relics to him." A thought seemed suddenly to strike her, and she opened her eyes very wide. "But where is the master?" she asked. "Why hasn't he come out?"

"He said he was going for a walk just after dinner," remarked Margaret quietly, "and I suppose he's not come back yet."

Larose took in the pale and beautiful face of the girl, and a pang of conscience seized him. "Poor little devil!" he murmured, "and I've killed the man who has perhaps been her lover! Oh! If she only knew it!" He nodded. "And she's in for more trouble. We'll have to arrest her now."

A few minutes later the little party returned to the Hall. Larose was able to get away unnoticed, and he hurried back to the plantation upon the Westleton road. He arrived just in time to see a car pull up and the unmistakable figure of Stone alight briskly. He called and beckoned to him.

"Well, they've decided not to wait another minute," announced the inspector, directly Larose had drawn level with him. "We're to arrest Mitter upon the charges of espionage they can already prove, and we are going to take the other man on spec, trusting to find out something about him when we've searched the place, and then——" But he broke off suddenly, and with his eyes glued to the black attache case Larose was carrying, asked sharply:—"What's that? Have you done any good?"

"Yes," nodded Larose, with a very weary smile, "and this is the attache case that belonged to Mitter. It contains four sets of artificial teeth, a naval beard and a scrubby beard, dark glasses and a case of make-up."

Then drawing the astonished inspector to one side, he told him everything that had happened. The eyes of Stone dilated like saucers and he breathed hard and heavily, as he listened to the tale. Then when Larose had finished he clucked his tongue, vigorously, against the roof of his mouth.

"And you're the luckiest man in creation," he said enviously. "You scoop the pool every time." He looked over his shoulder and lowered his voice to a whisper. "But see here, my son, I don't think anything of this had better come out, at any rate, we won't tell anyone now. We'll wait and see what the Intelligence people decide." He nodded. "Maybe, they'll think it best to let those two gentlemen remain where they are, and then there'll be no inquest, no publicity and no scandal."

"All right!" said Larose, "and we'll leave the searching of Dunwich Hall until to-morrow. We'll put in our calls to town and then off we'll all go to Saxmundham for a good meal and a night's rest. I'm worn out and feel I'm going to drop."

Stone hesitated a moment, and then nodded in agreement. "Yes, to-morrow will do," he said. "There's no hurry now."

He laid his hand upon Larose's arm. "But see here, have you got the formula he'd written down?" and when Larose in answer produced the wallet, and abstracted a blood-stained piece of paper for his inspection, he shuddered and turned away his eyes. "Gilbert, Gilbert," he murmured, "so often are you the Angel of Death!"

CHAPTER XV
THE JEST OF LIFE

LAROSE slept very badly that night. He was worried, and his thoughts would allow him no peace. He was not worried that he had first goaded Mitter to the point of frenzy and then had deliberatedly shot him through the heart, when he might so easily have only wounded him and then handed him over to the authorities.

He was not troubled there, for he knew Mitter was guilty of much more than they would ever have been able to prove, and by himself acting as judge and jury, as he had done, he had punished according to all canons of Justice; whereas Mitter's punishment by law would have certainly fallen far short of his deserts, and undoubtedly have been purged by a term of imprisonment only.

But it was about Margaret Advent he was so troubled, for when he had come to consider all that was in store for the girl, he felt profoundly sorry for her. She would, of course, have to be put on trial for complicity with Mitter, in the latter's work as a spy, and to whatsoever extent she was found to be implicated, it would, in any case, mean goodbye for ever to her romance with young Lieutenant Fortescue.

He knew he would have liked to think of Margaret as deserving of all she was now going to receive, and as a false little Jezebel who was only trying to make good for herself by inveigling young Fortescue into marrying her. But prejudiced as he was against her by the certain knowledge that she had been tampering with Dempster's letters, he was, somehow, unable to regard her in that light, for when from behind the clump of rhododendrons he had been watching her that night, it had come to him all suddenly as in a flash of intuition, that she was a good girl of a nice nature, and no light-of-love who would throw herself from one man to another, wherever she would get most of this world's pleasures.

He certainly could no longer visualise her as an unscrupulous schemer. Naturally, she would be wanting to get young Fortescue for a husband, as would not any girl in her position, but still, probably she was really in love with him, and every woman was entitled to seize her happiness when she could.

He nodded to himself here. No, he certainly did not pity young Fortescue, for the girl was so pretty that any man might be proud to have won her for a wife.

Then there was another aspect to everything that made Larose wish Margaret Advent were not going to be drawn into the matter. But for her, the story of Mitter's work as a spy, his torture of the professors, and his own violent death, might never come under the blaze of a most undesirable publicity, and the whole matter could have then been allowed to die down, and perhaps even, the bodies of Mitter and his confederate have never been recovered from the fallen masonry.

He, Larose, had told neither Stone, nor Carter, nor indeed anyone as yet of the part Margaret had been taking in helping Mitter, and if no mention were made of it now, everything could be hushed up, besides the girl being allowed to go free.

But Larose shook his head here. He liked to round off all his cases satisfactorily, and apart from that, the girl having been in Mitter's confidence, she might know a lot about Mitter's secret agents, and the information she could give be of incalculable value to the country.

He fell asleep at last and dreamed that he had kissed Margaret and agreed to say nothing about her to anyone, and that his wife had been very angry about it. But he told Helen the kiss had only been a fatherly one, and given only in the way of pity. Then she said she quite understood, and it was perfectly all right, and he had smiled when she wasn't looking and then been very furious with himself.

The following morning, a few minutes before nine o'clock, Larose and the two inspectors presented themselves at Dunwich Hall, and, finding the door open walked unceremoniously in.

They had arranged their plan of campaign, and were intending that nothing of what had really happened to Mitter and the supposed gardener should come out. All at the Hall were to be led to believe that the two had been arrested, but they were to be bound to silence about it to outsiders.

The butler, hearing the sound of voices, appeared immediately, and his face fell when he saw the little party.

"From Scotland Yard," said Larose, indicating the two inspectors, "and we've come to make a search of the house." He turned to Stone and Carter. "This is the Mr. Dempster who has been reporting to the Intelligence Department."

Stone gave the butler a friendly nod. "And we can be sure then," he said, "that he will help us in every way he can."

"We know that," interrupted Stone dryly, "and, what's more, he never will be again. You won't be seeing either Herr Mitter or his gardener any more."

Dempster at once went ghastly pale, but Larose patted him reassuringly upon the shoulder. "Never mind, my friend," he said kindly, "the Herr is much worse than any of us thought. He is a cruel and dreadful man, and it's a good thing for everyone that he has gone away." He spoke in crisp and business-like tones. "Now, you show these gentlemen where everything is. We'll examine the study first."

With a most unhappy expression upon his face, Dempster led the way to the study, with Larose hanging back and going last. Then when the Scotland Yard inspectors were inside the room, Larose said carelessly. "Well, I'll leave you for a few minutes, for I want to make a little investigation outside," and with a slight movement of the head to Dempster, he left the room.

The butler followed him, and then directly they were in the hall, Larose whispered sharply. "I want to speak to Miss Advent at once. Bring her to me in the morning room."

"But when did they take the master?" asked Dempster, with a catch in his voice. "It seems so dreadful to me!"

"Last night," said Larose, "when he was coming back from his walk, they took Sullivan, too. You'll hear all about it in a few minutes." He looked intently at the butler and lowered his voice confidingly. "Now, see here Dempster. I think it will be best for you to say nothing at all to these gentlemen about Miss Advent having been on such friendly terms with Herr Mitter, and tell your wife not to mention it, either, when they come to question her." He shook his head. "We don't want to make it unpleasant for the girl."

"Certainly not, sir," replied the butler, "and I'll say nothing about it." He looked round to see that they were not being overheard. "But she's leaving here this morning, sir. She's going up to London by the eleven o'clock train and she's packing her box now."

The butler shook his head. "No, sir. I'm almost sure he doesn't. She's only just told us half an hour ago." He looked very puzzled. "She knew the master did not come home last night, and I rather thinks she wants to get away before he returns."

Larose frowned. "Well, you go and fetch her now and don't forget what I've told you."

Margaret came into the room, looking pale and agitated, and she shut the door quickly behind her.

"Oh! Mr. Larose, tell me what's happened," she said breathlessly. "Has Herr Mitter really been taken away?"

Larose regarded her with a grim smile. "Well, everyone's not going to be told that," he said, "but with your knowledge of what Herr Mitter has been doing, I won't attempt to deceive you." He nodded. "Yes, he's gone and you won't be seeing him any more."

"And—" Margaret hesitated, "—and anyone else?" she asked, her voice trembling.

Larose laughed unpleasantly. "The gardener!" he said. "Yes, he's gone, too. They both went together." He pointed to a chair. "But you sit down, please. I want to talk to you." His face hardened and his voice became very stern. "Now, you look here, young lady, the sooner you realise your position, the better it will be for you. You understand?"

Her face at once lost something of its frightened look, and, steadying herself, she answered with a brave attempt at dignity. "No, I don't. What do you mean?"

"In about ten minutes," replied Larose impressively, "those detectives from Scotland Yard are going to start questioning you, and in half an hour I'm very much afraid you'll be under arrest and charged with spying under the direction of Herr Mitter."

"Oh!" came a startled exclamation from the girl, and her voice choked "but I've done nothing."

"Haven't you?" asked Larose scoffingly. "Think again, Miss Advent. What about those letters of Mr. Dempster you've been getting hold of and telling their contents to Herr Mitter?"

The girl's teeth snapped viciously. "You prove it," she said angrily. "You only overhead what Herr Mitter asked me that night when you had crept into the house like a common thief." Her eyes blazed. "And if I deny it, it will only be your word against mine. You can't prove it."

If Larose had been by himself he would have whistled, but instead, he looked very astonished and then he asked with a frown: "What do you know about my coming into the house any night?"

Margaret laughed scornfully. "Everything," she replied, enjoying his discomfiture. She nodded calmly. "That Mr. Dempster let you in through one window, and that you let yourself out through another, and that in between you picked one of Herr Mitter's pockets of a letter that he missed directly he went into his bedroom." She dropped her voice to a whisper. "Oh, yes, I know a lot about you, Mr. Larose, and, really, you ought to be very grateful to me, for I've befriended you more than once." She shook her head. "But I can keep a secret as well as anyone, and I'm not going to speak."

Larose could not contain his surprise. "What on earth do you mean?" he asked. "How have you befriended me?"

But Margaret shook her head again. "I'm not going to bring any charges against anyone," she said. "I don't want to be mixed up in anything. I was leaving here, at any rate, today, and shall be glad to be out of all the mess."

"Not so fast, Miss Margaret," said Larose sharply, "not so fast. I warn you. I tell you we are going to bring charges against you and you'll have to give some very unusual explanation if you're going to be allowed to go free."

The girls assurance left her at the grimness of his words and her face went pale again. "But you really can't be going to arrest me!" she exclaimed. "You've nothing against me!"

"That remains to be seen," nodded Larose, "when you've explained certain things that have been happening here."

Larose shrugged his shoulders. "I'm afraid no gentleman holding a commission under His Majesty will want to marry you, if that's what you mean"—he looked very hard at her—"Lieutenant Fortescue, for instance!"

Margaret winced and seemed now on the verge of tears. "Oh! then you know about him?" she asked, and when Larose nodded, she pulled herself together and demanded fiercely: "And what price am I to pay if you leave me alone?"' Her voice rose in contempt. "You have not got me here, by myself, for nothing. You must have something on your mind."

Larose felt very sorry for her distress. He had been trying to bully her, he knew, and it was contrary to his nature to act the bully at any time.

"Look here, Miss Advent," he said kindly, "you say you've been my friend, and I assure you I now want to be yours. So let's be quite frank with one another and show down all our cards." He smiled as if he were amused. "Now, do you agree?"

"Put yours down first," smiled back the girl, but her smile was a very sarcastic one. "I'll see if you've got anything of a hand." She looked him straight in the face. "I've done very little wrong, and that, through ignorance, so I'm not afraid of you."

Her insistence impressed Larose favorably and he spoke pleasantly and without the slightest trace of antagonism.

"Well, we've two things against you," he began, "or rather I have two things against you, for as yet I have said nothing about them to anyone. The first—knowing Herr Mitter to be a spy you have got hold of Dempster's letters for him, and the second—" his voice was very solemn—"for many months now you have been conniving at another man taking Herr Mitter's place in this house, while Mitter himself was away, spying as an enemy to this country."

Margaret seemed in no way nonplussed. "When I was suspecting him of being a spy I never stirred a finger to help him," she retorted sharply. "You heard that night how vexed he was with me because I made out I couldn't get hold of Mr. Dempster's letters any more." Her voice was scornful. "As for the conniving you talk about, well, I was a paid servant here and, as I've told you, I can hold my tongue. It was not my business what he went away for, and until recently I gave no thought to what his work was. Herr Mitter trusted me and in return I kept my mouth shut."

Margaret hesitated. "But you are asking me things now," she said. She smiled ironically. "Have you put down all your cards?"

Larose, frowningly ignored her question. "Listen, Miss Advent," he said. "You can make it so much easier for us, if you will—and to your own advantage, too. We want, to learn all the hidden life of this Carl Mitter. We have found out a great deal, but there are gaps that you may be able to fill in." He shook his head. "With all his charming ways. Mitter was an evil and cruel man, and——"

"Was?" queried Margaret and a startled look came into her eyes. "Was?" Her voice was so faint now that Larose had to bend forward to catch what she was saying. "Do you mean to tell me that he's dead?"

Larose took a sudden resolution. He was getting nothing out of the girl. Time was flying and any moment now she might be called for by the detectives. He could see she was of strong character and could be depended upon to hold her tongue. Well then, he would trust her.

He nodded. "Yes, he is dead." He said solemnly, "and the other man is dead, too. They both died last night and that is why we are here."

"By violent means," said Larose, "by deaths that they deserved, for they were dangerous enemies to the country and one, or both of them, were callous murderers." He shook his head. "You needn't grieve for them."

"I don't," choked Margaret. "I liked Herr Mitter very much, once, but lately things have been different, and I've learnt a lot and become afraid of both of them. I believe they were intending harm to me and that's why I was leaving so hurriedly this morning, to get away before either of them came back."

"Well, you can speak freely now," said Larose, "for you can't harm them. Now tell me who was this gardener, everyone knew as Sullivan?"

"His—" began Margaret and then she hesitated and looked doubtfully at Larose. "But how do I know," she said, "that you are telling me——"

"The truth," broke in Larose. He put his hand in his pocket and drew out a carefully folded packet that he proceeded to unwrap. Then he exposed a part of the wallet he had taken off the dead man. "Don't you recognise this?" he asked sharply, with his eyes fixed intently upon her.

He exposed the whole wallet and pointed to the hole the bullet had made, a hole surrounded by a dreadful-looking stain. "That's how he died," he said. "He was shot through the heart." His voice was low and menacing. "Mind you, I'm trusting you, as I expert you now to trust me. No one must know what I'm showing you, not even Mr. Fortescue. You understand?"

Margaret had closed her eyes. "Yes," she said faintly. "I understand. I won't tell anyone." She shuddered. "Oh! Put it away!"

"Now," said Larose, when he had re-wrapped the wallet and restored it to his pocket, "who was the gardener man?"

"His half-brother, Bernhard Mitter," she whispered. "They were sons of the same father. They were very much alike, when they were not made up in any disguise."

"And how long has this been going on," asked Larose, "this under-studying of Carl by Bernhard?"

"I don't know," replied Margaret. "I've only known of it myself for a little longer than six months." Her voice gained in strength. "You see, Mr. Larose, when I came here Herr Mitter was very kind to me, and seeing I was fairly well educated, he started training me to be his secretary. Then when he saw I kept myself away from the other servants, he began to trust me, and I did lots of little private things for him. Then one day he told me he was a political agent for his country, and was only living over here to find out how many ships England was building and things like that. He said every nation had men like him working in every country, and there was no harm in it, although, of course, he would be punished if he were found out. Then one night I came into his studio, unexpectedly, when he had forgotten to lock the door, and I saw Bernhard, as his brother, for the first time. They were taken by surprise and then, at first, Bernhard looked as if he would like to kill me. He——"

"But why?" interrupted Larose. "You didn't realise then that he was the gardener!"

"Oh! but I did," replied Margaret, "for he was dressed in Sullivan's clothes and, besides, he was holding Sullivan's red beard in his hand. He had torn it, accidentally, I learnt afterwards, and had come in to tell Herr Mitter another one must be got at once."

"In the way he always came," said Margaret, "through a door hidden behind the coats in the big cupboard at the end of the studio. This door opens into the alley between the old Priory walls, where no one ever goes. You can see the door, outside, but it's supposed to be walled up and no one knows it can be opened."

"Bernhard was very frightened, but Herr Mitter only laughed and said it was quite safe and I should never tell. Then he made me sit down and we all had a long talk together, and they told me that they had found out Dempster was paid to write to someone all that went on here, and they asked me to get hold of his letters and read them. I didn't like it at first, but when I read one letter and saw what they had said was quite true, I felt justified in opening every one I could get hold of."

Margaret shook her head. "No, but I've done it up to a little while ago, and then I stopped and made excuses that I couldn't get them, and it made Herr Mitter very angry. I know he didn't believe me."

Margaret hesitated. "Well," she said slowly, "Mr. Fortescue happened to say that foreign countries had got people working all over England, trying to find out the secret of those invisible aeroplanes, for it was only those aeroplanes that stood between us and another awful war. Then I realised what Herr Mitter must be doing, and resolved not to help him any more."

A short silence followed and then Larose asked. "What did you mean by saying you had lately become frightened of Herr Mitter? What have you found out he's done?"

Margaret smiled. "That day you stayed to lunch I saw him take something out of his medicine cupboard," she said, "from the place where I knew he usually kept a bottle of belladonna, and then I saw him pour some liquid into your glass of wine, when he was kneeling before the fire. That was why I told you there was cork in your wine and emptied it away."

"Oh! oh!" exclaimed Larose in great astonishment, "then I have to thank you for that!"

"Yes," said Margaret calmly, "and as I had seen Sullivan doing something underneath your car—when he had gone I took out one of your tools and put it upon the seat for you to notice. I thought perhaps it would make you suspicious."

"By Gad and it did!" exclaimed Larose. His face broke into a warm smile. "You're a good girl Margaret, and I'm very pleased I got this talk with you." He nodded. "Now, I'll keep you out of everything, as much as I can." He went on. "But do you know the names of anyone who's been working for Mitter?"

"Only one person," replied Margaret, "and I heard that about a fortnight ago when I was taking some glasses into the studio one night. They were whispering together and I caught something about a Captain Nathanial and some plans he had sent them." She heaved a big sigh. "That's all I know about anything."

"Good!" exclaimed Larose, "then this gentleman shall be looked up and caught out somehow. One more question, now. Which of them was Dr. Smith?"

Margaret looked very puzzled. "I've never heard of him," she said, shaking her head. "He's never been here that I know of."

"Well, which of the two was in the habit of going up to London," asked Larose, "sometimes upon every day of one week?"

"It might have been either of them," replied Margaret, "or perhaps both, or they may have taken it in turns. Bernhard, like Herr Mitter, was often away for a whole week at a time. Every one then supposed he had gone on the drink."

They talked on for a few minutes and then Larose said very earnestly. "Now it's a good thing you've been quite frank with me, for I see no reason at all why you should be dragged into the business"—he looked very serious—"but you're not quite out of the wood yet. You're going to be questioned by two of the shrewdest men in Scotland Yard, and you must be careful that nothing you have just told me, comes out. Just answer the question they put to you, and say as little as you can. Volunteer nothing on your own, and know nothing about this Bernhard. Just appear to be what they think you are, an ordinary parlormaid and not too intelligent. You understand?"

She nodded. "And do you think I shall be able to go away this morning as I intended?" she asked.

"Yes, if you don't make a slip and they become suspicious," said Larose. He shook hands with her, warmly. "I am very grateful to you and, as I say, I'll help you all I can."

In the meantime, the butler had been having an uncomfortable time, for he had been told plainly by the inspectors that he must be somewhat of a fool. He had been flabbergasted when he had been informed that all the time it was the gardener, Sullivan, upon whom he had been waiting, when his master had been supposed to be so engrossed upon his painting, and he had been upon the point of excusing himself by telling them that Margaret had been deceived also. But he remembered Larose warning and, at some strain of his dignity, kept silent. He was very relieved when at last, very discomforted and all clammy with perspiration, he was allowed to leave the room.

Larose had returned to the others by the time Margaret was called in. Stone elevated his eyebrows and made a half wink at Larose as she entered the room. "Something snappy," he whispered, "and looks very intelligent. We ought to learn something here."

It was Carter who first took Margaret in hand, telling her that her master having gone away, and there being certain reasons to think he would not be returning, they were desirous of finding out all they could about his ways and the people who were accustomed to visit the Hall.

"On—" began Margaret, hesitatingly to the horrified dismay of Larose, who saw Stone frown and his eyebrows come together with a click, "—on the stroke of half past seven last night when I had cleared away the dinner things, and was leaving the studio."

"You are very exact, Miss Advent," smiled Carter, who was apparently drawing nothing from the girl's hesitation and the framing of her answer.

"Well, I remember hearing the clock strike," replied Margaret, "just as I was closing the door."

"And had your master seemed in his usual spirits yesterday?" went on the inspector.

Margaret shook her head. "He's never in good spirits when he's painting," she replied, "and when the light fails, he seems exhausted and quite worn out."

"Damn!" swore Larose under his breath, "if she goes on volunteering information like that, she'll make a slip very soon!"

Margaret considered. "Only that at dinner he told me he would be going out later," she said, "and I was to leave the kettle on the hob, in case he would be wanting any hot water."

Margaret shook her head. "I don't think I noticed," she said. She gave a faint shrug with her shoulders. "He seemed quite all right, for he was smoking all day."

Then Carter asked her about the people who were accustomed to come to the house, and at his request she wrote down as many of the names that she could remember.

Then Stone took his turn at questioning her, and at once Larose felt uncomfortable when he noticed the genial smile with which the inspector was regarding her. He knew that smile so well, and that it boded no good for anyone who was trying to keep anything back.

"And we understand you are leaving here this morning, Miss Advent," said Stone. He elevated his eyebrows. "That is a rather sudden act on your part, isn't it?"

"I heard Herr Mitter had not been home all night. Mr. Dempster said his bed had not been slept in, and I wanted to get away before he returned."

"Oh!" exclaimed Stone, and his eyebrows were elevated still higher, "then your master does not know you are leaving?"

"Not that I am leaving today," replied Margaret promptly, "but he has known for weeks, now, that I intended to go." She nodded. "But he wants me to remain on, and has made no attempt to get anyone to fill my place. He has kept on putting off the day when he can spare me."

"But what do you want to leave for, so urgently?" asked Stone. "This is a comfortable place, is it not?"

"Very comfortable," replied Margaret, "or I shouldn't have stopped here as I have done, for nearly two years. Herr Mitter has been very kind to me. But I am leaving now to better myself. I'm not badly educated and I'm going to take a course of training to become a secretary, somewhere."

Stone frowned. "But isn't it rather ungracious," he said, "considering Herr Mitter has been so kind to you, as you say, to be going away like this, when you don't know what's happened to him? Of course, you've heard he's gone off without taking a hat or an overcoat, and so he may have met with some dreadful accident!"

Margaret shook her head. "I don't think so," she said. "Most likely he's going fishing with the Dunwich fishermen and they'll have lent him oilskins, and all he wants." She spoke quickly. "You see, sir, Herr Mitter is very reserved at all times and never tells anyone what he's going to do. So we are accustomed to his ways and take everything as it comes. Sometimes he hardly speaks to us for days on end together."

"Hum!" remarked Stone rather dubiously, "then what did you think when you heard we had arrived here, and Mr. Dempster told you we were from the police?"

"But you must have thought something," persisted Stone. "Something must have flashed into your mind!"

"Oh! yes, something did," replied Margaret at once. "I know he is a foreigner and I thought"—she hesitated—"I thought that perhaps he had been interfering in political matters."

Again Margaret hesitated, but this time much longer. "Trying to find out things he shouldn't," she replied at length as if choosing her words with the utmost care.

"Spying! you mean?" rapped out Stone and his words came like a bullet from a gun. "You mean he had been caught spying?" and when Margaret nodded uncomfortably, he dropped his voice to stern and accusing tones. "Then you had reason to believe, Miss Advent, that your master was a spy?"

Larose was on tenter-hooks. The girl was so obviously becoming confused and any moment now he expected her to break down. Then, to his great relief, she drew up confidently and smiled as if she were amused.

"Good gracious! I'm hardly as imaginative as that," she laughed. "No, but when I heard from Mr. Dempster that you were from the police, a remark that a friend of mine had made some weeks ago when I was out with him one night, instantly came back to me."

"That lots of foreigners over here would give anything to find out of what those new aeroplanes of ours are made, and no doubt many things were going on to try and get hold of the secret."

"And that remark of course," snapped Stone, "was made when you were talking about Herr Mitter, and was a pointed reference to him."

"Oh! no it wasn't," replied Margaret instantly. "This gentleman knows Herr Mitter and likes him very much."

"But I'm not going to tell you that," said Margaret, shaking her head determinedly. "There's no reason why I should," and then seeing that the inspector was looking very stern and grim, she added with an arch smile. "Mr. Larose knows who he is," and Larose although rather discomfited at his name being brought in, at once nodded to Stone that her statement was correct.

Inspector Stone did some quick thinking. The girl was exceptionally pretty, some man had taken her out one night, Larose knew who the man was, and now Larose himself was looking uncomfortable. Therefore, he, Stone, guessed he knew who the man was, and he repressed a smile and looked down his nose.

"Well, well," he said, after a long pause and he spoke much more quietly now, "where is this training place you are going to?"

"In London," replied Margaret. "Collard's Business College, Gresham street, City."

Margaret shook her head. "I have no parents," she said. "I am an orphan. No. I'm going to find lodgings somewhere."

Stone frowned again. "But if we want to speak to you," he said, "if we want to ask you some more questions, how shall we get in touch with you?"

For a few moments Margaret looked perplexed, and then she blushed and her face broke into a smile. She nodded towards Larose. "Mr. Larose will be able to tell you," she said. "He'll always know how to find me."

There was a dead silence then. Stone looked down his nose again, and Larose felt himself getting rather red. "I think you'd better explain, Miss Advent," he said with a frown, "and let these gentlemen understand there is no mystery about anything."

Instantly Margaret sensed something of what was in the inspector's mind, and her blush now became a furious one.

"I'm going to be married to this gentleman I've been speaking about," she said quickly, "and I don't want to give his name, simply because he's in a much better station of life than I am. In fact he's an officer in His Majesty's army and, naturally, he would not like everyone to know he's marrying someone who's been in domestic service. Really, that's why I'm leaving here and going to a training college. Mr. Larose happens to know my friend and has been told by him about our intended marriage." She turned to Larose. "That is so, is it not?"

Larose nodded. "Yes, it's quite all right, Inspector Stone," he said, "and this young lady's fiance comes of a very distinguished family. His name, of course, can be disclosed to you, if you wish, but I see no reason for it."

The face of Stone was now all smiles and geniality. "Quite all right, quite all right," he exclaimed, "and I'm sure I don't want to know. If Mr. Larose says he can find you if you're wanted, then that's good enough for anyone."

He asked Margaret a few more questions and then after an interchange of glances with Inspector Carter, dismissed her with the smiling remark that he was sure her fiance was a very lucky fellow.

Some two hours later, however, when Inspector Stone and the others were interestedly regarding the great mass of fallen masonry, the inspector squeezed Larose's arm and whispered with a chuckle.

"I'm not quite such an old fool as you may think, my boy, and I'm sure that young lady could have told us much more than she did—and you know it, too." He poked him in the ribs. "You may always represent justice, Gilbert, but no one is better aware than I am that you don't always represent law, and if I did my duty I should worry this pretty Miss Margaret a great deal more." He stretched out one big, fat hand. "But still, what's the good of swatting a butterfly with this"—his eyes sparkled mischeviously—"and such a pretty butterfly too."

"You're a good fellow, Charlie," whispered back Larose, "and take it from me, you're doing no wrong. That girl's as innocent as a baby, and yet a lot of clumsy questioning might have ruined her whole life." He nodded. "Maybe you'll see her again some day and then, won't you be surprised!"

THE following week the staff at Dunwich Hall were paid off and the house shut up. It was rumored Herr Mitter had been called abroad, and in the absence of instructions from him, nothing was done to the ruins of the chapel wall.

About a year and half later, Mr. and Mrs. Gilbert Larose were present one night at the Royal Opera House in Covent Garden to hear the famous Signor Aronelli in the role of Faust. The house was packed to its utmost capacity, and they were occupying seats in the stalls.

Just before the curtain rose two men just in front of them started to talk, and they overheard their conversation.

"My word!" exclaimed one of the men looking up at a box not very far away, "but there's a lovely girl, if you like. I don't think I've ever seen one more beautiful. I wonder who she is?"

The other man looked in the direction he indicated. "Oh! She's Lady Fortescue," he said, "and that's her husband with her, the Baronet, Sir Selby Fortescue. He came into the baronetcy about six months ago, when his cousin, Wing-Commander Fortescue, crashed somewhere in Wales, and the uncle died from shock almost immediately afterwards."

"Well, hardly," laughed the other. "She had a baby a little while back, but still I don't think they've been married very long."

Mrs. Larose was most interested. "Did you hear that, Gilbert?" she whispered, and when her husband had nodded, she looked very puzzled, and went on, "but I seem to know her face, somewhere. I must have met her somewhere, although it seems that I remember she was dressed very differently, then."

Larose smiled to himself. "Perhaps it was at some fancy dress ball, dear," he remarked. "I often can't place faces, myself."

"Oh! but she's looking our way," exclaimed Mrs. Larose. "She's bowing to you, Gilbert!"

"So she is!" said Larose, and when he had bowed and smiled in return, he whispered to his wife: "I think I must have met her that year at Lord Batten's when you weren't with me."

"Well, you must have made an impression," whispered back Mrs. Larose as the curtain began to rise, "for I saw she gave you a most lovely blush!" She caressed her husband's hand in the darkness. "I shall still have to look after you, I see, Gilbert."

ONE afternoon a respectable-looking but very poorly dressed woman walked up the steps of the Foundling Hospital. She was just beyond middle age, but evidently had been attractive once, for she had refined, clear-cut features and large, liquid grey eves. Her hands were small and finely shaped. She appeared to be very nervous.

Asking to see the secretary, and being ushered into his presence, she said she had come to make enquiries about a baby girl who had been left there nearly twenty-four years previously.

She then proceeded to give particulars, but the secretary interrupted her by asking upon whose behalf she had come.

The secretary shook his head. "Then I'm sorry," he said, "but I can't tell you anything. Your friend must come herself and prove to our satisfaction that she has the right to make the enquiries. We disclose no information, generally, about any child that has been left here."

"But if she does come," asked the woman shakily, "do you think you would be able to tell her what has become of the child and where she is now?"

The secretary looked doubtful. "Twenty-four years is a long time to go back," he said, "and although we try to keep in touch with all our children, we find so many of them as they prow up, prefer to forget all about us." He shook his head. "They don't want it to be known they've been left here."

The woman went out with a very downcast air, and at the street corner was joined by a man about her own age. He, too, was poorly clad and if his face had not looked drawn and pale, as if from ill-health, he would certainly have been not unhandsome. She told him what had taken place.

"So you see it's no good, Jim," she said, "and we must leave it as it is. They might imprison us if we admitted we had done it, and besides, if we did find our baby she mightn't be pleased about it. We, certainly, can't give her anything, and she may be much happier as she is." Her eyes filled with tears. "It's our punishment, Jim."

"Well, never mind, Meg," said the man linking his arm affectionately in hers. "We must try and find a bit of happiness for ourselves. Come on back to that registry office now. Who knows we mayn't get a nice place together in the country, and then you'll have a little garden with flowers, and I'll be able to keep fowls. It's good country air I want, and then I shall grow strong again."

ONE afternoon, towards dusk, about a week later, when Lady Fortescue, in her beautiful home in Sussex, was watching with adoring eyes the antics of her little son who was lying upon a rug before the fire, the door of the room opened and her husband entered.

"Hullo! Margaret," he exclaimed gaily, "baby-worshipping as usual! Really, you'll quite spoil the little beggar and the sooner I give you three or four to keep him company the better."

"Thank you, old dear," laughed his wife, putting up her face for him to kiss, "but you'll kindly wait, please, until I ask you for them." She drew back suddenly. "Oh! but I've something to tell you. I've engaged the new lodge-keeper and his wife."

"The ones we heard about," enquired her husband, "the man who had been ill and was once butler with Sir Pompey?"

"Yes, and they're such a nice old couple," said Lady Fortescue, "the real old-fashioned sort. The man's so respectful, and the woman's got such a nice face, although it's awfully sad. They've been married for twenty years, but funnily enough have never managed to get in service together, before. He's been ill and out of work lately, and, she's kept him with her sewing. They're coming in to-morrow, and what do you think?" Margaret shook her head. "It was quite pathetic. The poor old fellow asked if he might keep a few fowls."

"Oh!" grunted the baronet, "and I suppose you promised him a dozen of my prize Rhode Island Reds to start off with."

Sir Selby made a mock gesture of resignation. "Have your own way, Margaret," he sighed, "as you always do."

"Oh! yes!" exclaimed Lady Fortescue, "and her name's Margaret, too, although he calls her Meg."

"Dreadful," exclaimed her husband, "how people in that class so often spoil beautiful names! Fancy anyone calling you Meg!" His face brightened. "But I've got something to tell you. With whom do you think I've been golfing this afternoon?"

"The old bishop, perhaps," suggested his wife, "in which case I hope you didn't swear too much."

"No," laughed Sir Selby, "not the bishop, or the rector or the curate or the doctor,"—he nodded impressively—"but with no less a person than Gilbert Larose, and what's more, as he and his wife are staying with Colonel Bevan, I asked the Colonel to bring them here to-morrow." He looked intently at her. "You don't mind, do you, sweetheart?"

"Certainly not," she replied, although her face had flushed a little. "I am sure Mr. Larose would never say anything, even to his wife."

"And I agree, darling. Men don't tell those sort of things, and although I heard someone at the club say the other day that Mr. Larose ought to have hanged many times for the things he's done, I have a very high opinion of the lord of Carmel Abbey."

"And so have I," said Lady Fortescue solemnly. "I'd trust him with my life, honor and everything." Her eyes took on a faraway look. "He's a very just and human man."

The Master Spy

by

Arthur Gask

TABLE OF CONTENTS

CHAPTER I
BY THE DARK NORTH SEA

CHAPTER II
DISEASES OF THE SKIN

CHAPTER III
THE SPY

CHAPTER IV
THE SECRETS OF FOULNESS

CHAPTER V
LAROSE TAKES UP THE TRAIL

CHAPTER VI
THE CONSPIRATORS

CHAPTER VII
A DUEL OF WITS

CHAPTER VIII
HOT UPON THE TRAIL

CHAPTER IX
RUN TO EARTH

CHAPTER X
THE ADVENTURES OF MARGARET ADVENT

CHAPTER XI
DEADLY NIGHTSHADE

CHAPTER XII
THE KIDNAPPING OF THE PROFESSOR

CHAPTER XIII
THE HEATED IRON

CHAPTER XIV
THE BURIAL OF THE DEAD

CHAPTER XV
THE JEST OF LIFE

THE END

The Master Spy

by

Arthur Gask

TABLE OF CONTENTS

CHAPTER I BY THE DARK NORTH SEA

CHAPTER II DISEASES OF THE SKIN

CHAPTER III THE SPY

CHAPTER IV THE SECRETS OF FOULNESS

CHAPTER V LAROSE TAKES UP THE TRAIL

CHAPTER VI THE CONSPIRATORS

CHAPTER VII A DUEL OF WITS

CHAPTER VIII HOT UPON THE TRAIL

CHAPTER IX RUN TO EARTH

CHAPTER X THE ADVENTURES OF MARGARET ADVENT

CHAPTER XI DEADLY NIGHTSHADE

CHAPTER XII THE KIDNAPPING OF THE PROFESSOR

CHAPTER XIII THE HEATED IRON

CHAPTER XIV THE BURIAL OF THE DEAD

CHAPTER XV THE JEST OF LIFE

THE END

CHAPTER I
BY THE DARK NORTH SEA

CHAPTER II
DISEASES OF THE SKIN

CHAPTER III
THE SPY

CHAPTER IV
THE SECRETS OF FOULNESS

CHAPTER V
LAROSE TAKES UP THE TRAIL

CHAPTER VI
THE CONSPIRATORS

CHAPTER VII
A DUEL OF WITS

CHAPTER VIII
HOT UPON THE TRAIL

CHAPTER IX
RUN TO EARTH

CHAPTER X
THE ADVENTURES OF MARGARET ADVENT

CHAPTER XI
DEADLY NIGHTSHADE

CHAPTER XII
THE KIDNAPPING OF THE PROFESSOR

CHAPTER XIII
THE HEATED IRON

CHAPTER XIV
THE BURIAL OF THE DEAD

CHAPTER XV
THE JEST OF LIFE