Some days after the recovery of the houseboat, Average Jones sat at breakfast, according to his custom, in the cafe of the Hotel Palatia. Several matters were troubling his normally serene mind. First of these was the loss of the trail which should have led to Harvey Craig. Second, as a minor issue, the Oriental papers found in the deserted Bellair Street apartment had been proved, by translation, to consist mainly of revolutionary sound and fury, signifying, to the person most concerned, nothing. As for the issue of the Washington daily, culled from the houseboat, there was, amidst the usual melange of social, diplomatic, political and city news, no marked passage to show any reason for its having been in the possession of “Smith.” Average Jones had studied and restudied the columns, both reading matter and advertising, until he knew them almost by heart. During the period of waiting for his order to be brought he was brooding over the problem, when he felt a hand-pressure on his shoulder and turned to confront Mr. Thomas Colvin McIntyre, solemn of countenance and groomed with a supernal modesty of elegance, as befitted a rising young diplomat, already Fifth Assistant Secretary of State of the United States of America.

“Hello, Tommy,” said the breakfaster. “What'll you have to drink? An entente cordialer?”

“Don't joke,” said the other. “I'm in a pale pink funk. I'm afraid to look into the morning papers.”

“Hello! What have you been up to that's scandalous?”

“It isn't me,” replied the diplomat ungrammatically. “It's Telfik Bey.”

“Telfik Bey? Wait a minute. Let me think.” The name had struck a response from some thought wire within Average Jones' perturbed brain. Presently it came to him as visualized print in small head-lines, reproduced to the mind's eye from the Washington newspaper which he had so exhaustively studied.

No arrest, it appeared, had been made. The “story,” indeed, was brief, and of no intrinsic importance other than as a social note. But to Average Jones it began to glow luminously.

“Who is Telfik Bey?” he inquired.

“He isn't. Up to yesterday he was a guest of this hotel.”

“Indeed! Skipped without paying his bill?”

“Yes—ah. Skipped—that is, left suddenly without paying his bill, if you choose to put it that way.”

The tone was significant. Average Jones' good natured face became grave.

“Oh, I beg your pardon, Tommy. Was he a friend of yours?”

“No. He was, in a sense, a ward of the Department, over here on invitation. This is what has almost driven me crazy.”

Fumbling nervously in the pocket of his creaseless white waistcoat he brought forth a death notice.

“From the Dial,” he said, handing it to Average Jones.

The clipping looked conventional enough.

“If the newspapers ever discover—” The young diplomat stopped short before the enormity of the hypothesis.

“It looks straight enough to me as a death notice, except for the tail. What does 'Ana Alhari' mean? Sort of a requiescat?”

“Yes; like a mice!” said young Mr. McIntyre bitterly. “It means 'Hurrah!' That's the sort of requiescat it is!”

“Ah! Then they got him the second time.”

“What do you mean by 'second time?”'

“The Washington incident, of course, was the first; the attempted murder—that is, the narrow escape of Telfik Bey.”

Young Mr. McIntyre looked baffled. “I'm blessed if I know what you're up to, Jones,” he said. “But if you do know anything of this case I need your help. In Washington, where they failed, we fooled the newspapers. Here, where they've succeeded—“'

“Who are 'they?'” interrupted Jones.

“That's what I'm here to get at. The murderers of Telfik Bey, of course. My instructions are to find out secretly, if at all. For if it does get into the newspapers there'll be the very deuce to pay. It isn't desirable that even Telfik Bey's presence here should have been known for reasons which—ah—(here Average Jones remarked the resumption of his friend's official bearing)—which, not being for the public, I need not detail to you.”

“You need not, in point of fact, tell me anything about it at all,” observed Average Jones equably.

Pomposity fell away from Mr. Thomas Colvin McIntyre, leaving him palpably shivering.

“But I need your help. Need it very much. You know something about handling the newspapers, don't you?”

“I know how to get things in; not how to keep them out.”

The other groaned. “It may already be too late. What newspapers have you there?”

“All of 'em. Want me to look?”

Mr. McIntyre braced himself.

“Turk dies at Palatia,” read Average Jones. “Mm—heart disease... wealthy Stamboul merchant... studying American methods... Turkish minister notified.”

“Is that all?”

“Practically.”

“And the other reports?”

Average Jones ran them swiftly over. “About the same. Hold on! Here's a little something extra in the Universal.”

“'Found on the floor... bell-boy who discovered the tragedy collapses... condition serious... Supposedly shock—”

“What's that?” interrupted young Mr. McIntyre, half rising. “Shot?”

“You're nervous, Tommy. I didn't say 'shot.' Said 'shock.”'

“Oh, of course. Shock—the bell-boy, it means.”

“See here; first thing you know you'll be getting me interested. Hadn't you better open up or shut up?”

Mr. McIntyre took a long breath and a resolution simultaneously.

“At any rate I can trust you,” he said. “Telfik Bey is not a merchant. He is a secret, confidential agent of the Turkish government. He came over to New York from Washington in spite of warnings that he would be killed.”

“You're certain he was killed?”

“I only wish I could believe anything else.”

“Shot?”

“The coroner and a physician whom I sent can find no trace of a wound.”

“What do they say?”

“Apoplexy.”

“The refuge of the mystified medico. It doesn't satisfy you?”

“It won't satisfy the State Department.”

“And possibly not the newspapers, eventually.”'

“Come up with me and look the place over, Average. Let me send for the manager.”

That functionary came, a vision of perturbation in a pale-gray coat. Upon assurance that Average Jones was “safe” he led the way to the rooms so hastily vacated by the spirit of the Turkish guest.

“We've succeeded in keeping two recent suicides and a blackmail scheme in this hotel out of the newspapers,” observed the manager morosely. “But this would be the worst of all. If I could have known, when the Turkish Embassy reserved the apartment—”

“The Turkish Embassy never reserved any apartment for Telfik Bey,” put in the Fifth Assistant Secretary of State.

“Surely you are mistaken, sir,” replied the hotel man. “I saw their emissary myself. He specified for rooms on the south side, either the third or fourth floor. Wouldn't have anything else.”

“You gave him a definite reservation?” asked Jones.

“Yes; 335 and 336.”

“Has the man been here since?”

“Not to my knowledge.”

“A Turk, you think?”

“I suppose so. Foreign, anyway.”

“Anything about him strike you particularly?”

“Well, he was tall and thin and looked sickly. He talked very soft, too, like a sick man.”

The characterization of the Pearlington station agent recurred to the interrogator's mind. “Had he—er—white hair?” he half yawned.

“'No,” replied the manager, and, in the same breath, the budding diplomat demanded:

“What are you up to, Average? Why should he?”

Average Jones turned to him. “To what other hotels would the Turkish Embassy be likely to send its men?”

“Sometimes their charge d'affaires goes to the Nederstrom.”

“Go up there and find out whether a room has been reserved for Telfik Bey, and if so—”

“They wouldn't reserve at two hotels, would they?”

“By whom,” concluded Average Jones, shaking his head at the interruption. “Find out who occupied or reserved the apartments on either side.”

Mr. Thomas Colvin McIntyre lifted a wrinkling eyebrow. “Really, Jones,” he observed, “you seem to be employing me rather in the capacity of a messenger boy.”

“If you think a messenger boy could do it as well, ring for one,” drawled Average Jones, in his mildest voice. “Meantime, I'll be in the Turk's room here.”

Numbers 335 and 336, which the manager opened, after the prompt if somewhat sulky departure of Mr. McIntyre, proved to consist of a small sitting room, a bedroom and a bath, each with a large window giving on the cross-street, well back from Fifth Avenue.

“Here's where he was found.” The manager indicated a spot near the wall of the sitting-room and opposite the window. “He had just pushed the button when he fell.”

“How do you know that?”

“Bronson, the bell-boy on that call, answered. He knocked several times and got no answer. Then he opened the door and saw Mr. Telfik down, all in a heap.”

“Where is Bronson?”

“At the hospital, unconscious.”

“What from?”

“Shock, the doctors say.”

“What—er—about the—er—shot?”

The manager looked startled. “Well, Bronson says that just as he opened the door he saw a bullet cross the room and strike the wall above the body.”

“You can't see a bullet in flight.”

“He saw this one,” insisted the manager. “As soon as it struck it exploded. Three other people heard it.”

“What did Bronson do?”

“Lost his head and ran out. He hadn't got halfway to the elevator when he fell, in a sort of fainting fit. He came to long enough to tell his story. Then he got terribly nauseated and went off again.”

“He's sure the man had fallen before the explosion?”

“Absolutely.”

“And he got no answer to his knocking?”

“No. That's why he went in. He thought something might be wrong.”

“Had anybody else been in the room or past it within a few minutes?”

“Absolutely no one. The floor girl's desk is just outside. She must have seen anyone going in.”

“Has she anything to add?”

“She heard the shot. And a minute or two before, she had heard and felt a jar from the room.”

“Corroborative of the man having fallen before the shot,” commented Jones.

“When I got here, five minutes later, he was quite dead,” continued the manager.

Evidence of the explosion was slight to the investigating eye of Average Jones. The wall showed an abrasion, but, as the investigator expected, no bullet hole. Against the leg of a desk he found a small metal shell, which he laid on the table.

“There's your bullet,” he observed with a smile.

“It's a cartridge, anyway,” cried the hotel man. “He must have been shot, after all.”

“From inside the room? Hardly! And certainly not with that. It's a very small fulminate of mercury shell, and never held lead. No. The man was down, if not dead, before that went off.”

Average Jones was now at the window. Taking a piece of paper from his pocket he brushed the contents of the window-sill upon it. A dozen dead flies rolled upon the paper. He examined them thoughtfully, cast them aside and turned back to the manager.

“Who occupy the adjoining rooms?”

“Two maiden ladies did, on the east. They've left,” said the manager bitterly. “Been coming here for ten years, and now they've quit. If the facts ever get in the newspapers—”

“What's on the west, adjoining?”

“Nothing. The corridor runs down there.”

“Then it isn't probable that any one got into the room from either side.”

“Impossible,” said the manager.

Here Mr. Thomas Colvin McIntyre arrived with a flushed face.

“You are right, Average,” he said. “The same man had reserved rooms at the Nederstrom for Telfik Bey.”

“What's the location?”

“Tenth floor; north side. He had insisted on both details. Nos. 1015, 1017.”

“What neighbors?”

“Bond salesman on one side, Reverend and Mrs. Salisbury, of Wilmington, on the other.”

“Um-m-m. What across the street?”

“How should I know? You didn't tell me to ask.”

“It's the Glenargan office building, just opened, Mr. Jones,” volunteered the manager.

Average Jones turned again to the window, closed it and fastened his handkerchief in the catch. “Leave that there,” he directed the manager. “Don't let any one into this room. I'm off.”

Stopping to telephone, Average Jones ascertained that there were no vacant offices on the tenth floor, south side of the Glenargan apartment building, facing the Nederstrom Hotel. The last one had been let two weeks before to—this he ascertained by judicious questioning—a dark, foreign gentleman who was an expert on rugs. Well satisfied, the investigator crossed over to the skyscraper across from the Palatia. There he demanded of the superintendent a single office on the third floor, facing north. He was taken to a clean and vacant room. One glance out of the window showed him his handkerchief, not opposite, but well to the west.

“Too near Fifth Avenue,” he said. “I don't like the roar of the traffic.”

“There's one other room on this floor, farther along,” said the superintendent, “but it isn't in order. Mr. Perkins' time isn't up till day after tomorrow, and his things are there yet. He told the janitor, though, that he was leaving town and wouldn't bother to take away the things. They aren't worth much. Here's the place.”

They entered the office. In it were only a desk, two chairs and a scrap basket. The basket was crammed with newspapers. One of them was the Hotel Register. Average Jones found Telfik Bey's name, as he had expected, in its roster.

“I'll give fifty dollars for the furniture as it stands.”

“Glad to get it,” was the prompt response. “Will you want anything else, now?”

“Yes. Send the janitor here.”

That worthy, upon receipt of a considerable benefaction, expressed himself ready to serve the new tenant to the best of his ability.

“Do you know when Mr. Perkins left the building?”

“Yes, sir. This morning, early.”

“This morning! Sure it wasn't yesterday?”

“Am I sure? Didn't I help him to the street-car and hand him his little package? That sick he was he couldn't hardly walk alone.”

Average Jones pondered a moment. “Do you think he could have passed the night here?”

“I know he did,” was the prompt response. “The scrubwoman heard him when she came this morning.”

“Heard him?”

“Yes' sir. Sobbing, like.”

The nerves of Average Jones gave a sharp “kickback,” like a mis-cranked motor-car. His trend of thought had suddenly been reversed. The devious and scientific slayer of Telfik Bey in tears? It seemed completely out of the picture.

“You may go,” said he, and seating himself at the desk, proceeded to an examination of his newly acquired property. The newspapers in the scrap basket, mainly copies of the Evening Register, seemed to contain, upon cursory examination, nothing germane to the issue. But, scattered among them, the searcher found a number of fibrous chips. They were short and thick; such chips as might be made by cutting a bamboo pole into cross lengths, convenient for carrying.

“The 'spirit-wand,”' observed Average Jones with gusto. “That was the 'little package,' of course.”

Next, he turned his attention to the desk. It was bare, except for a few scraps of paper and some writing implements. But in a crevice there shone a glimmer of glass. With a careful finger-nail Average Jones pushed out a small phial. It had evidently been sealed with lead. Nothing was in it.

Its discoverer leaned back and contemplated it with stiffened eyelids. For, upon its tiny, improvised label was scrawled the “Mercy sign;” mysterious before, now all but incredible.

For silent minutes Average Jones sat bemused. Then, turning in a messenger call, he drew to him a sheet of paper upon which he slowly and consideringly wrote a few words.

“You get a dollar extra if this reaches the advertising desk of the Register office within half an hour,” he advised the uniformed urchin who answered the call. The modern mercury seized the paper and fled forthwith.

Punctuality was a virtue which Average Jones had cultivated to the point of a fad. Hence it was with some discountenance that his clerk was obliged to apologize for his lateness, first, at 4 P. M. Of July 23, to a very dapper and spruce young gentleman in pale mauve spats, who wouldn't give his name; then at 4:05 P. m. of the same day to Professor Gehren, of the Metropolitan University; and finally at 4:30 P. m. to Mr. Robert Bertram. When, only a moment before five, the Ad-Visor entered, the manner of his apology was more absent than fervent.

Bertram held out a newspaper to him.

“Cast your eye on that,” said he. “The Register fairly reeks with freaks lately.”

Average Jones read aloud.

“Oh, I don't know about its being so freakish,” said Average Jones.

“Nonsense! Look at it! Turkish Triumph—that's a cigarette, isn't it? H. C.—what's that? And signed Mercy. Why, it's the work of a lunatic!”

“It's my work,” observed Average Jones blandly.

The three visitors stared a him in silence.

“Rather a forlorn hope, but sometimes a bluff will go,” he continued.

“If H. C. indicates Harvey Craig, as I infer,” said Professor Gehren impatiently, “are you so infantile as to suppose that his murderer will give information about him?”

Average Jones smiled, drew a letter from his pocket, glanced at it and called for a number in Hackensack.

“Take the 'phone, Professor Gehren,” he said, when the reply came. “It's the Cairnside Hospital. Ask for information about Harvey Craig.”

With absorbed intentness the other three listened to the one-sided conversation.

“Hello!... May I speak to Mr. Harvey Craig's doctor?... This is Professor Gehren of the Metropolitan University... Thank you, Doctor. How is he?... Very grave?... Ah, has been very grave .... Wholly out of danger?... What was the nature of his illness?

“When may I see him?... Very well. I will visit the hospital to-morrow morning. Thank you.... I should have expected that you would notify me of his, presence.” intervened, then “Good-by.”

“It is most inexplicable,” declared Professor Gehren, turning to the others. “The doctor states that Harvey was brought there at night, by a foreigner who left a large sum of money to pay for his care, and certain suggestions for his treatment. One detail, carefully set down in writing, was that if reddish or purple dots appeared under Harvey's nails, he was to be told that Mr. Smith released him and advised his sending for his friends at once.”

“Reddish or purple dots, eh?” repeated Average Jones. “I should like—er—to have talked with—er—that doctor before you cut off.”

“And I, sir,” said the professor, with the grim repression of the thinker stirred to wrath, “should like to interview this stranger.”

“Perfectly feasible, I think,” returned Average Jones.

A long silence.

“You don't mean that you've located him already!” cried young Mr. McIntyre.

“He was so obliging as to save me the trouble.”

Average Jones held up the letter from which he had taken the Cairnside Hospital's telephone number. “The advertisement worked to a charm. Mr. Smith gives his address in this, and intimates that I may call upon him.”

Young Mr. McIntyre rose.

“You're going to see him, then?”

“At once.”

“Did I understand you to imply that I am at liberty to accompany you?” inquired Professor Gehren.

“If you care to take the risk.”

“Think there'll be excitement?” asked Bertram languidly. “I'd like to go along.”

Average Jones nodded. “One or a dozen; I fancy it will be all the same to Smith.”

“You think we'll find him dead.” Young Mr. McIntyre leaped to this conclusion. “Count me in on it.”

“N-no; not dead.”

“Perhaps his friend 'Mercy' has gone back on him, then,” suggested Mr. McIntyre, unabashed.

“Yes; I rather think that's it,” said Average Jones, in a curious accent. “'Mercy' has gone back on him, I believe, though I can't quite accurately place her as yet. Here's the taxi,” he broke off. “All aboard that's going aboard. But it's likely to be dangerous.”

Across town and far up the East Side whizzed the car, over the bridge that leads away from Manhattan Island to the north, and through quiet streets as little known to the average New Yorker as are Hong Kong and Caracas. In front of a frame house it stopped. On a side porch, over which bright roses swarmed like children clambering into a hospitable lap, sat a man with a gray face. He was tall and slender, and his hair, a dingy black, was already showing worn streaks where the color had faded. At Average Jones he gazed with unconcealed surprise.

“Ah; it is you!” he exclaimed. “You,” he smiled, “are the 'Mercy' of the advertisement?”

“Yes.”

“And these gentlemen?”

“Are my friends.”

“You will come in?”

Average Jones examined a nodding rose with an indulgent, almost a paternal, expression.

“If you—er—think it—er—safe,” he murmured.

“Assuredly.”

As if exacting a pledge the young man held out his hand. The older one unhesitatingly grasped it. Average Jones turned the long fingers, which enclosed his, back upward, and glanced at them.

“Ah,” he said, and nodded soberly, “so, it is that.”

“Yes; it is that,” assented the other. “I perceive that you have communicated with Mr. Craig. How is he?”

“Out of danger.”

“That is well. A fine and manly youth. I should have sorely regretted it if—”

Professor Gehren broke in upon him. “For the peril in which you have involved him, sir, you have to answer to me, his guardian.”

The foreigner raised a hand. “He was without family or ties. I told him the danger. He accepted it. Once he was careless—and one is not careless twice in that work. But he was fortunate, too. I, also, was fortunate in that the task was then so far advanced that I could complete it alone. I got him to the hospital at night; no matter how. For his danger and illness I have indemnified him in the sum of ten thousand dollars. Is it enough?”

Professor Gehren bowed.

“And you, Mr. Jones; are you a detective?”

“No; merely a follower of strange trails—by taste.”

“Ah. You have set yourself to a dark one. You wish to know how Telfik Bey”—his eyes narrowed and glinted—“came to his reward. Will you enter, gentlemen?”

“I know this much,” replied Average Jones as, followed by his friends, he passed through the door which their host held open. “With young Craig as an assistant, you prepared, in the loneliest part of the Hackensack Meadows, some kind of poison which, I believe, can be made with safety only in the open air.”

The foreigner smiled and shook his head.

“Not with safety, even then,” he said. “But go on.”

“You found that your man was coming to New York. Knowing that he would probably put up at the Palatia or the Nederstrom, you reserved rooms for him at both, and took an office across from each. As it was hot weather, you calculated upon his windows being open. You watched for him. When he came you struck him down in his own room with the poison.”

“But how?” It was the diplomat who interrupted.

“I think with a long blow-gun.”

“By George!” said Bertram softly. “So the spirit-wand of bamboo was a blow-gun! What led you to that, Average?”

“The spirit rappings, which the talky woman in the Bellair Street apartment used to hear. That and the remnants of putty I found near the window. You see the doors opening through the whole length of the apartment gave a long range, where Mr.—er—Smith could practice. He had a sort of target on the window, and every time he blew a putty ball Mrs. Doubletongue heard the spirit. Am I right, sir?”

The host bowed.

“The fumes, whatever they were, killed swiftly?”

“They did. Instantly; mercifully. Too mercifully.”

“How could you know it was fumes?” demanded Mr. Thomas Colvin McIntyre.

“By the dead flies, the effect upon the bell-boy, and the fact that no wound was found on the body. Then, too, there was the fulminate of mercury shell.”

“Of what possible use was that?” asked Professor Gehren.

“A question that I've asked myself, sir, a great many times over in the last twenty-four hours. Perhaps Mr. Smith could answer that best. Though—er—I think the shell was blown through the blowpipe to clear the deadly fumes from the room by its explosion, before any one else should suffer. Smith is, at least, not a wanton slaughterer.”

“You are right, sir, and I thank you,” said the foreigner. He drew himself up weakly but with pride. “Gentlemen, I am not a murderer. I am an avenger. It would have gone hard with my conscience had any innocent person met death through me. As for that Turkish dog, you shall judge for yourself whether he did not die too easily.”

From among the papers in a tiroir against the wall he took a French journal, and read, translating fluently. The article was a bald account of the torture, outrage and massacre of Armenian women and girls, at Adana, by the Turks. The most hideous portion of it was briefly descriptive of the atrocities perpetrated by order of a high Turkish official upon a mother and two young daughters. “An Armenian prisoner, being dragged by in chains, went mad at the sight,” the correspondent stated.

“I was that prisoner,” said the reader. “The official was Telfik Bey. I saw my naked daughter break from the soldiers and run to him, pleading for pity, as he sat his horse; and I saw him strike his spur into her bare breast. My wife, the mother of my children—”

“Don't!” The protest came from the Fifth Assistant Secretary of State.

He had risen. His smooth-skinned face was contracted, and the sweat stood beaded on his forehead. “I—I can't stand it. I've got my duty to do. This man has made a confession.”

“Your pardon,” said the foreigner. “I have lived and fed on and slept with that memory, ever since. On my release I left my country. The enterprise of which I had been the head, dye-stuff manufacturing, had interested me in chemistry. I went to England to study further. Thence I came to America to wait.”

“You have heard his confession, all of you,” said young Mr. McIntyre, rising. “I shall have him put under arrest pending advice from Washington.”

“You, may save yourself the trouble, I think, Tommy,” drawled Average Jones. “Mr. Smith will never be called to account in this world for the murder—execution of Telfik Bey.”

“You saw the marks on my finger-nails,” said the foreigner. “That is the sure sign. I may live twenty-four hours; I may live twice or three times that period. The poison does its work, once it gets into the blood, and there is no help. It matters nothing. My ambition is satisfied.”

“And it is because of this that you let us find you?” asked Bertram.

“I had a curiosity to know who had so strangely traced my actions.”

“But what was the poison?” asked Professor Gehren.

“I think Mr. Jones has more than a suspicion,” replied the doomed man, with a smile. “You will find useful references on yonder shelf, Mr. Jones.”

Moving across to the shelf, Average Jones took down a heavy volume and ran quickly over the leaves.

“Ah!” he said presently, and not noticing, in his absorption, that the host had crossed again to the tiroir and was quietly searching in a compartment, he read aloud:

“Little is known of cyanide of cacodyl, in its action the swiftest and most deadly of existing poisons. In the '40's, Bunsen, the German chemist, combined oxide of cacodyl with cyanogen, a radical of prussic acid, producing cyanide of cacodyl, or diniethyl arsine cyanide. As both of its components are of the deadliest description, it is extremely dangerous to make. It can be made only in the open air, and not without the most extreme precaution known to science. Mr. Lacelles Scott, of England, nearly lost his life experimenting with it in 1904. A small fraction of a grain gives off vapor sufficient to kill a human being instantly.”

“Had you known about this stuff, Average?” asked Bertram.

“No, I'd never beard of it. But from its action and from the lettered cabinet, I judged that—”

“This is all very well,” broke in Mr. Assistant Secretary Thomas Colvin McIntyre, “but I want this man arrested. How can we know that he isn't shamming and may not escape us, after all?”

“By this,” retorted their host. He held aloft a small glass vial, lead-seated, and staggered weakly to the door.

“Stop him!” said Average Jones sharply.

The door closed on the words. There was a heavy fall without, followed by the light tinkle of glass.

Average Jones, who had half crossed the room in a leap, turned to his friends, warning them back.

“Too late. We can't go out yet. Wait for the fumes to dissipate.”

They stood, the four men, rigid. Presently Average Jones, opening a rear window, leaped to the ground, followed by the others, and came around the corner of the porch. The dead man lay with peaceful face. Professor Gehren uncovered.

“God forgive him,” he said. “Who shall say that he was not right?”

“Not I,” said the young assistant secretary in awed tones. “I'm glad he escaped. But what am I to do? Here we are with a dead body on our hands, and a state secret to be kept from the prying police.”

Average Jones stood thinking for a moment, then he entered the room and called up the coroner's office on the telephone.

“Listen, you men,” he said to his companions. Then, to the official who answered: “There's a suicide at 428 Oliver Avenue, the Bronx. Four of us witnessed it. We had come to keep an appointment with the man in connection with a discovery he claimed in metallurgy, and found him dying. Yes; we will wait here. Good-by.”

Returning to the porch again, he cleared away the fragments of glass, aided by Bertram. To one of these clung a shred of paper. For all his languid self-control the club dilettante shivered a little as he thrust at it with a stick.

“Look, Average, it's the 'Mercy' sign again. What a hideous travesty!”

Average Jones shook his bead.

“It isn't 'Mercy,' Bert. It's the label that he attached, for precaution, to everything that had to do with his deadly stuff. The formula for cyanide of cacodyl is 'Me-2CY.' It was the scrawly handwriting that misled; that's all.”

“So I was right when I suggested that his 'Mercy' had gone back on him,” said Mr. Thomas Colvin McIntyre, with a semi-hysterical giggle.

Average Jones looked from the peaceful face of the dead to the label, fluttering in the light breeze.

“No,” he said gravely. “You were wrong. It was his friend to the last.”