That night I was sitting, brooding over the case, while Craig was studying a photograph which he made of the smudge on the glass door down at Schloss'. He paused in his scrutiny of the print to answer the telephone.

"Something has happened to Schloss," he exclaimed seizing his hat and coat. "Winters has been watching him. He didn't go to the Recherche. Winters wants me to meet him at a place several blocks below it Come on. He wouldn't say over the wire what it was. Hurry."

We met Winters in less than ten minutes at the address he had given, a bachelor apartment in the neighborhood of the Recherche.

"Schloss kept rooms here," explained Winters, hurrying us quickly upstairs. "I wanted you to see before anyone else."

As we entered the large and luxuriously furnished living room of the jeweler's suite, a gruesome sight greeted us.

There lay Schloss on the floor, face down, in a horribly contorted position. In one hand, clenched under him partly, the torn sleeve of a woman's dress was grasped convulsively. The room bore unmistakable traces of a violent struggle, but except for the hideous object on the floor was vacant.

Kennedy bent down over him. Schloss was dead. In a corner, by the door, stood a pile of grips, stacked up, packed, and undisturbed.

Winters who had been studying the room while we got our bearings picked up a queer-looking revolver from the floor. As he held it up I could see that along the top of the barrel was a long cylinder with a ratchet or catch at the butt end. He turned it over and over carefully.

"By George," he muttered, "it has been fired off."

Kennedy glanced more minutely at the body. There was not a mark on it. I stared about vacantly at the place where Winters had picked the thing up.

"Look," I cried, my eye catching a little hole in the baseboard of the woodwork near it.

"It must have fallen and exploded on the floor," remarked Kennedy. "Let me see it, Winters."

Craig held it at arm's length and pulled the catch. Instead of an explosion, there came a cone of light from the top of the gun. As Kennedy moved it over the wall, I saw in the center of the circle of light a dark spot.

"A new invention," Craig explained. "All you need to do is to move it so that little dark spot falls directly on an object. Pull the trigger—the bullet strikes the dark spot. Even a nervous and unskilled marksman becomes a good shot in the dark. He can even shoot from behind the protection of something—and hit accurately."

It was too much for me. I could only stand and watch Kennedy as he deftly bent over Schloss again and placed a piece of chemically prepared paper flat on the forehead of the dead man.

When he withdrew it, I could see that it bore marks of the lines on his head. Without a word, Kennedy drew from his pocket a print of the photograph of the smudge on Schloss' door.

"It is possible," he said, half to himself, "to identify a person by means of the arrangement of the sweat glands or pores. Poroscopy, Dr. Edmond Locard, director of the Police Laboratory at Lyons, calls it. The shape, arrangement, number per square centimeter, all vary in different individuals. Besides, here we have added the lines of the forehead."

He was studying the two impressions intensely. When he looked up from his examination, his face wore a peculiar expression.

"This is not the head which was placed so close to the glass of the door of Schloss' office, peering through, on the night of the robbery, in order to see before picking the lock whether the office was empty and everything ready for the hasty attack on the safe."

"That disposes of my theory that Schloss robbed himself," remarked Winters reluctantly. "But the struggle here, the sleeve of the dress, the pistol—could he have been shot?"

"No, I think not," considered Kennedy. "It looks to me more like a case of apoplexy."

"What shall we do?" asked Winters. "Far from clearing anything up, this complicates it."

"Where's Muller?" asked Kennedy. "Does he know? Perhaps he can shed some light on it."

The clang of an ambulance bell outside told that the aid summoned by
Winters had arrived.

We left the body in charge of the surgeon and of a policeman who arrived about the same time, and followed Winters.

Muller lived in a cheap boarding house in a shabbily respectable street downtown, and without announcing ourselves we climbed the stairs to his room. He looked up surprised but not disconcerted as we entered.

"What's the matter?" he asked.

"Muller," shot out Winters, "we have just found Mr. Schloss dead!"

"D-dead!" he stammered.

The man seemed speechless with horror.

"Yes, and with his grips packed as if to run away."

Muller looked dazedly from one of us to the other, but shut up like a clam.

"I think you had better come along with us as a material witness," burst out Winters roughly.

Kennedy said nothing, leaving that sort of third degree work to the detective. But he was not idle, as Winters tried to extract more than the monosyllables, "I don't know," in answer to every inquiry of Muller about his employer's life and business.

A low exclamation from Craig attracted my attention from Winters. In a corner he had discovered a small box and had opened it. Inside was a dry battery and a most peculiar instrument, something like a little flat telephone transmitter yet attached by wires to earpieces that fitted over the head after the manner of those of a wireless detector.

"What's this?" asked Kennedy, dangling it before Muller.

He looked at it phlegmatically. "A deaf instrument I have been working on," replied the jeweler. "My hearing is getting poor."

Kennedy looked hastily from the instrument to the man.

"I think I'll take it along with us," he said quietly.

Winters, true to his instincts, had been searching Muller in the meantime. Besides the various assortment that a man carries in his pockets usually, including pens, pencils, notebooks, a watch, a handkerchief, a bunch of keys, one of which was large enough to open a castle, there was a bunch of blank and unissued pawn-tickets bearing the name, "Stein's One Per Cent. a Month Loans," and an address on the Bowery.

Was Muller the "fence" we were seeking, or only a tool for the "fence" higher up? Who was this Stein?

What it all meant I could only guess. It was a far cry from the wealth of Diamond Lane to a dingy Bowery pawnshop, even though pawnbroking at one per cent. a month—and more, on the side—pays. I knew, too, that diamonds are hoarded on the East Side as nowhere else in the world, outside of India. It was no uncommon thing, I had heard, for a pawnbroker whose shop seemed dirty and greasy to the casual visitor to have stored away in his vault gems running into the hundreds of thousands of dollars.

"Mrs. Moulton must know of this," remarked Kennedy. "Winters, you and
Jameson bring Muller along. I am going up to the Deluxe."

I must say that I was surprised at finding Mrs. Moulton there. Outside the suite Winters and I waited with the unresisting Muller, while Kennedy entered. But through the door which he left ajar I could hear what passed.

"Mrs. Moulton," he began, "something terrible has happened—"

He broke off, and I gathered that her pale face and agitated manner told him that she knew already.

"Where is Mr. Moulton?" he went on, changing his question.

"Mr. Moulton is at his office," she answered tremulously. "He telephoned while I was out that he had to work to-night. Oh, Mr. Kennedy—he knows—he knows. I know it. He has avoided me ever since I missed the replica from-"

"Sh!" cautioned Craig. He had risen and gone to the door.

"Winters," he whispered, "I want you to go down to Lynn Moulton's office. Meanwhile Jameson can take care of Muller. I am going over to that place of Stein's presently. Bring Moulton up there. You will wait here, Walter, for the present," he nodded.

He returned to the room where I could hear her crying softly.

"Now, Mrs. Moulton," he said gently, "I'm afraid I must trouble you to go with me. I am going over to a pawnbroker's on the Bowery."

"The Bowery?" she repeated, with a genuinely surprised shudder. "Oh, no, Mr. Kennedy. Don't ask me to go anywhere to-night. I am—I am in no condition to go anywhere—to do anything—I—"

"But you must," said Kennedy in a low voice.

"I can't. Oh—have mercy on me. I am terribly upset. You—"

"It is your duty to go, Mrs. Moulton," he repeated.

"I don't understand." she murmured. "A pawnbroker's?"

"Come," urged Kennedy, not harshly but firmly, then, as she held back, added, playing a trump card, "We must work quickly. In his hands we found the fragments of a torn dress. When the police—"

She uttered a shriek. A glance had told her, if she had deceived herself before, that Kennedy knew her secret.

Antoinette Moulton was standing before him, talking rapidly.

"Some one has told Lynn. I know it. There is nothing now that I can conceal. If you had come half an hour later you would not have found me. He had written to Mr. Schloss, threatening him that if he did not leave the country he would shoot him at sight. Mr. Schloss showed me the letter.

"It had come to this. I must either elope with Schloss, or lose his aid. The thought of either was unendurable. I hated him—yet was dependent on him.

"To-night I met him, in his empty apartment, alone. I knew that he had what was left of his money with him, that everything was packed up. I went prepared. I would not elope. My plan was no less than to make him pay the balance on the necklace that he had lost—or to murder him.

"I carried a new pistol in my muff, one which Lynn had just bought. I don't know how I did it. I was desperate.

"He told me he loved me, that Lynn did not, never had—that Lynn had married me only to show off his wealth and diamonds, to give him a social! position—that I was merely a—a piece of property—a dummy.

"He tried to kiss me. It was revolting. I struggled away from him.

"And in the struggle, the revolver fell from my muff and exploded on the floor.

"At once he was aflame with suspicion.

"'So—it's murder you want!' he shouted. 'Well, murder it shall be!'

"I saw death in his eye as he seized my arm. I was defenseless now. The old passion came over him. Before he killed—he—would have his way with me.

"I screamed. With a wild effort I twisted away from him.

"He raised his hand to strike me, I saw his eyes, glassy. Then he sank back—fell to the floor—dead of apoplexy—dead of his furious emotions.

"I fled.

"And now you have found me."

She had turned, hastily, to leave the room. Kennedy blocked the door.

"Mrs. Moulton," he said firmly, "listen to me. What was the first question you asked me? 'Can I trust you?' And I told you you could. This is no time for—for suicide." He shot the word out bluntly. "All may not be lost. I have sent for your husband. Muller is outside."

"Muller?" she cried. "He made the replica."

"Very well. I am going to clear this thing up. Come. You MUST."

It was all confused to me, the dash in a car to the little pawnbroker's on the first floor of a five-story tenement, the quick entry into the place by one of Muller's keys.

Over the safe in back was a framework like that which had covered Schloss' safe. Kennedy tore it away, regardless of the alarm which it must have sounded. In a moment he was down before it on his knees.

"This is how Schloss' safe was opened so quickly," he muttered, working feverishly. "Here is some of their own medicine."

He had placed the peculiar telephone-like transmitter close to the combination lock and was turning the combination rapidly.

Suddenly he rose, gave the bolts a twist, and the ponderous doors swung open.

"What is it?" I asked eagerly.

"A burglar's microphone," he answered, hastily looking over the contents of the safe. "The microphone is now used by burglars for picking combination locks. When you turn the lock, a slight sound is made when the proper number comes opposite the working point. It can be heard sometimes by a sensitive ear, although it is imperceptible to most persons. But by using a microphone it is an easy matter to hear the sounds which allow of opening the lock."

He had taken a yellow chamois bag out of the safe and opened it.

Inside sparkled the famous Moulton diamonds. He held them up—in all their wicked brilliancy. No one spoke.

Then he took another yellow bag, more dirty and worn than the first. As he opened it, Mrs. Moulton could restrain herself no longer.

"The replica!" she cried. "The replica!"

Without a word, Craig handed the real necklace to her. Then he slipped the paste jewels into the newer of the bags and restored both it and the empty one to their places, banged shut the door of the safe, and replaced the wooden screen.

"Quick!" he said to her, "you have still a minute to get away.
Hurry—anywhere—away—only away!"

The look of gratitude that came over her face, as she understood the full meaning of it was such as I had never seen before.

"Quick!" he repeated.

It was too late.

"For God's sake, Kennedy," shouted a voice at the street door, "what are you doing here?"

It was McLear himself. He had come with the Hale patrol, on his mettle now to take care of the epidemic of robberies.

Before Craig could reply a cab drew up with a rush at the curb and two men, half fighting, half cursing, catapulted themselves into the shop.

They were Winters and Moulton.

Without a word, taking advantage of the first shock of surprise,
Kennedy had clapped a piece of chemical paper on the foreheads of Mrs.
Moulton, then of Moulton, and on Muller's. Oblivious to the rest of us,
he studied the impressions in the full light of the counter.

Moulton was facing his wife with a scornful curl of the lip.

"I've been told of the paste replica—and I wrote Schloss that I'd shoot him down like the dog he is, you—you traitress," he hissed.

She drew herself up scornfully.

"And I have been told why you married me—to show off your wicked jewels and help you in your—"

"You lie!" he cried fiercely. "Muller—some one—open this safe—whosever it is. If what I have been told is true, there is in it one new bag containing the necklace. It was stolen from Schloss to whom you sold my jewels. The other old bag, stolen from me, contains the paste replica you had made to deceive me."

It was all so confused that I do not know how it happened. I think it was Muller who opened the safe.

"There is the new yellow bag," cried Moulton, "from Schloss' own safe.
Open it."

McLear had taken it. He did so. There sparkled not the real gems, but the replica.

"The devil!" Moulton exclaimed, breaking from Winters and seizing the old bag.

He tore it open and—it was empty.

"One moment," interrupted Kennedy, looking up quietly from the counter. "Seal that safe again, McLear. In it are the Schloss jewels and the products of half a dozen other robberies which the dupe Muller—or Stein, as you please—pulled off, some as a blind to conceal the real criminal. You may have shown him how to leave no finger prints, but you yourself have left what is just as good—your own forehead print. McLear—you were right. There's your criminal—Lynn Moulton, professional fence, the brains of the thing."