At this point the tension was so great that it snapped. Miss La Neige, who was sitting beside me, had been leaning forward involuntarily.

Almost as if the words were wrung from her she whispered hoa.r.s.ely: "They put me up to doing it; I didn't want to. But the affair had gone too far. I couldn't see him lost before my very eyes. I didn't want her to get him. The quickest way out was to tell the whole story to Mr. Parker and stop it. It was the only way I could think of to stop this thing between another man's wife and the man I loved better than my own husband. G.o.d knows, Professor Kennedy, that was all--"

"Calm yourself, madame," interrupted Kennedy soothingly. "Calm yourself.

What's done is done. The truth must come out. Be calm. Now," he continued, after the first storm of remorse had spent itself and we were all outwardly composed again, "we have said nothing whatever of the most mysterious feature of the case, the firing of the shot. The murderer could have thrust the weapon into the pocket or the folds of this coat"--here he drew forth the automobile coat and held it aloft, displaying the bullet hole--"and he or she (I will not say which) could have discharged the pistol unseen. By removing and secreting the weapon afterward one very important piece of evidence would be suppressed.

This person could have used such a cartridge as I have here, made with smokeless powder, and the coat would have concealed the flash of the shot very effectively. There would have been no smoke. But neither this coat nor even a heavy blanket would have deadened the report of the shot.

"What are we to think of that? Only one thing. I have often wondered why the thing wasn't done before. In fact I have been waiting for it to occur. There is an invention that makes it almost possible to strike a man down with impunity in broad daylight in any place where there is sufficient noise to cover up a click, a slight 'Pouf!' and the whir of the bullet in the air.

"I refer to this little device of a Hartford inventor. I place it over the muzzle of the thirty-two-calibre revolver I have so far been using--so. Now, Mr. Jameson, if you will sit at that typewriter over there and write--anything so long as you keep the keys clicking. The inspector will start that imitation stock-ticker in the corner. Now we are ready. I cover the pistol with a cloth. I defy anyone in this room to tell me the exact moment when I discharged the pistol. I could have shot any of you, and an outsider not in the secret would never have thought that I was the culprit. To a certain extent I have reproduced the conditions under which this shooting occurred.

"At once on being sure of this feature of the case I despatched a man to Hartford to see this inventor. The man obtained from him a complete list of all the dealers in New York to whom such devices had been sold. The man also traced every sale of those dealers. He did not actually obtain the weapon, but if he is working on schedule-time according to agreement he is at this moment armed with a search-warrant and is ransacking every possible place where the person suspected of this crime could have concealed his weapon. For, one of the persons intimately connected with this case purchased not long ago a silencer for a thirty-two-calibre revolver, and I presume that that person carried the gun and the silencer at the time of the murder of Kerr Parker."

Kennedy concluded in triumph, his voice high pitched, his eyes flashing.

Yet to all outward appearance not a heart-beat was quickened. Someone in that room had an amazing store of self-possession. The fear flitted across my mind that even at the last Kennedy was baffled.

"I had antic.i.p.ated some such anti-climax," he continued after a moment.

"I am prepared for it."

He touched a bell, and the door to the next room opened. One of Kennedy's graduate students stepped in.

"You have the records, Whiting" he asked.

"Yes, Professor."

"I may say," said Kennedy, "that each of your chairs is wired under the arm in such a way as to betray on an appropriate indicator in the next room every sudden and undue emotion. Though it may be concealed from the eye, even of one like me who stands facing you, such emotion is nevertheless expressed by physical pressure on the arms of the chair. It is a test that is used frequently with students to demonstrate various points of psychology. You needn't raise your arms from the chairs, ladies and gentlemen. The tests are all over now. What did they show, Whiting?"

The student read what he had been noting in the next room. At the production of the coat during the demonstration of the markings of the bullet, Mrs. Parker had betrayed great emotion, Mr. Bruce had done likewise, and nothing more than ordinary emotion had been noted for the rest of us. Miss La Neige's automatic record during the tracing out of the sending of the note to Parker had been especially unfavourable to her; Mr. Bruce showed almost as much excitement; Mrs. Parker very little and Downey very little. It was all set forth in curves drawn by self-recording pens on regular ruled paper. The student had merely noted what took place in the lecture-room as corresponding to these curves.

"At the mention of the noiseless gun," said Kennedy, bending over the record, while the student pointed it out to him and we leaned forward to catch his words, "I find that the curves of Miss La Neige, Mrs. Parker, and Mr. Downey are only so far from normal as would be natural. All of them were witnessing a thing for the first time with only curiosity and no fear. The curve made by Mr. Bruce shows great agitation and--"

I heard a metallic click at my side and turned hastily. It was Inspector Barney O'Connor, who had stepped out of the shadow with a pair of hand-cuffs.

"James Bruce, you are under arrest," he said.

There flashed on my mind, and I think on the minds of some of the others, a picture of another electrically wired chair.

II. The Scientific Cracksman

"I'm willing to wager you a box of cigars that you don't know the most fascinating story in your own paper to-night," remarked Kennedy, as I came in one evening with the four or five newspapers I was in the habit of reading to see whether they had beaten the Star in getting any news of importance.

"I'll bet I do," I said, "or I was one of about a dozen who worked it up. It's the Shaw murder trial. There isn't another that's even a bad second."

"I am afraid the cigars will be on you, Walter. Crowded over on the second page by a lot of stale sensation that everyone has read for the fiftieth time, now, you will find what promises to be a real sensation, a curious half-column account of the sudden death of John G. Fletcher."

I laughed. "Craig," I said, "when you put up a simple death from apoplexy against a murder trial, and such a murder trial; well, you disappoint me--that's all."

"Is it a simple case of apoplexy?" he asked, pacing up and down the room, while I wondered why he should grow excited over what seemed a very ordinary news item, after all. Then he picked up the paper and read the account slowly aloud.

JOHN G. FLETCHER, STEEL MAGNATE, DIES SUDDENLY

SAFE OPEN BUT LARGE SUM OF CASH UNTOUCHED

John Graham Fletcher, the aged philanthropist and steelmaker, was found dead in his library this morning at his home at Fletcherwood, Great Neck, Long Island. Strangely, the safe in the library in which he kept his papers and a large sum of cash was found opened, but as far as could be learned nothing is missing.

It had always been Mr. Fletcher's custom to rise at seven o'clock. This morning his housekeeper became alarmed when he had not appeared by nine o'clock. Listening at the door, she heard no sound. It was not locked, and on entering she found the former steel-magnate lying lifeless on the floor between his bedroom and the library adjoining. His personal physician, Dr. W. C. Bryant, was immediately notified.

Close examination of the body revealed that his face was slightly discoloured, and the cause of death was given by the physician as apoplexy. He had evidently been dead about eight or nine hours when discovered.

Mr. Fletcher is survived by a nephew, John G. Fletcher, II., who is the Blake professor of bacteriology at the University, and by a grandniece, Miss Helen Bond. Professor Fletcher was informed of the sad occurrence shortly after leaving a cla.s.s this morning and hurried out to Fletcherwood. He would make no statement other than that he was inexpressibly shocked. Miss Bond, who has for several years resided with relatives, Mr. and Mrs. Francis Greene of Little Neck, is prostrated by the shock.

"Walter," added Kennedy, as he laid down the paper and, without any more sparring, came directly to the point, "there was something missing from that safe."

I had no need to express the interest I now really felt, and Kennedy hastened to take advantage of it.

"Just before you came in," he continued, "Jack Fletcher called me up from Great Neck. You probably don't know it, but it has been privately reported in the inner circle of the University that old Fletcher was to leave the bulk of his fortune to found a great school of preventive medicine, and that the only proviso was that his nephew should be dean of the school. The professor told me over the wire that the will was missing from the safe, and that it was the only thing missing. From his excitement I judge that there is more to the story than he cared to tell over the 'phone. He said his car was on the way to the city, and he asked if I wouldn't come and help him--he wouldn't say how. Now, I know him pretty well, and I'm going to ask you to come along, Walter, for the express purpose of keeping this thing out of the newspapers understand?--until we get to the bottom of it."

A few minutes later the telephone rang and the hall-boy announced that the car was waiting. We hurried down to it; the chauffeur lounged down carelessly into his seat and we were off across the city and river and out on the road to Great Neck with amazing speed.

Already I began to feel something of Kennedy's zest for the adventure.

I found myself half a dozen times on the point of hazarding a suspicion, only to relapse again into silence at the inscrutable look on Kennedy's face. What was the mystery that awaited us in the great lonely house on Long Island?

We found Fletcherwood a splendid estate directly on the bay, with a long driveway leading up to the door. Professor Fletcher met us at the porte cochere, and I was glad to note that, far from taking me as an intruder, he seemed rather relieved that someone who understood the ways of the newspapers could stand between him and any reporters who might possibly drop in.

He ushered us directly into the library and closed the door. It seemed as if he could scarcely wait to tell his story.

"Kennedy," he began, almost trembling with excitement, "look at that safe door."

We looked. It had been drilled through in such a way as to break the combination. It was a heavy door, closely fitting, and it was the best kind of small safe that the state of the art had produced. Yet clearly it had been tampered with, and successfully. Who was this scientific cracksman who had apparently accomplished the impossible? It was no ordinary hand and brain which had executed this "job."

Fletcher swung the door wide, and pointed to a little compartment inside, whose steel door had been jimmied open. Then out of it he carefully lifted a steel box and deposited it on the library table.

"I suppose everybody has been handling that box?" asked Craig quickly.

A smile flitted across Fletcher's features. "I thought of that, Kennedy," he said. "I remembered what you once told me about finger-prints. Only myself has touched it, and I was careful to take hold of it only on the sides. The will was placed in this box, and the key to the box was usually in the lock. Well, the will is gone. That's all; nothing else was touched. But for the life of me I can't find a mark on the box, not a finger-mark. Now on a hot and humid summer night like last night I should say it was pretty likely that anyone touching this metal box would have left finger-marks. Shouldn't you think so, Kennedy?"

Kennedy nodded and continued to examine the place where the compartment had been jimmied. A low whistle aroused us: coming over to the table, Craig tore a white sheet of paper off a pad lying there and deposited a couple of small particles on it.

"I found them sticking on the jagged edges of the steel where it had been forced," he said. Then he whipped out a pocket magnifying-gla.s.s.

"Not from a rubber glove," he commented half to himself. "By Jove, one side of them shows lines that look as if they were the lines on a person's fingers, and the other side is perfectly smooth. There's not a chance of using them as a clue, except--well, I didn't know criminals in America knew that stunt."

"What stunt?"

"Why, you know how keen the new detectives are on the finger-print system? Well, the first thing some of the up-to-date criminals in Europe did was to wear rubber gloves so that they would leave no prints. But you can't work very well with rubber gloves. Last fall in Paris I heard of a fellow who had given the police a lot of trouble. He never left a mark, or at least it was no good if he did. He painted his hands lightly with a liquid rubber which he had invented himself. It did all that rubber gloves would do and yet left him the free use of his fingers with practically the same keenness of touch. Fletcher, whatever is at the bottom of this affair, I feel sure right now that you have to deal with no ordinary criminal."

"Do you suppose there are any relatives besides those we know of?" I asked Kennedy when Fletcher had left to summon the servants.