“Well, that’s that.” Heath seemed well satisfied with Inspector Brenner’s conclusion. “I’ll send the box down to you, Professor, and you can let me know what else you find out.”

“I’ll take it along, if you have no objection.” And the little man tucked it under his arm and shuffled out without another word.

Heath grinned at Markham. “Queer bird. He ain’t happy unless he’s measuring jimmy marks on doors and windows and things. He couldn’t wait till I sent him the box. He’ll hold it lovingly on his lap all the way down in the subway, like a mother with a baby.”

Vance was still standing near the dressing-table, gazing perplexedly into space.

“Markham,” he said, “the condition of that jewel-case is positively astounding. It’s unreasonable, illogical—insane. It complicates the situation most damnably. That steel box simply couldn’t have been chiselled open by a professional burglar … and yet, don’t y’ know, it actually was.”

Before Markham could reply, a satisfied grunt from Captain Dubois attracted our attention.

“I’ve got something for you, Sergeant,” he announced.

We moved expectantly into the living-room. Dubois was bending over the end of the library-table almost directly behind the place where Margaret Odell’s body had been found. He took out an insufflator, which was like a very small hand-bellows, and blew a fine light-yellow powder evenly over about a square foot of the polished rosewood surface of the table-top. Then he gently blew away the surplus powder, and there appeared the impression of a human hand distinctly registered in saffron. The bulb of the thumb and each fleshy hummock between the joints of the fingers and around the palm stood out like tiny circular islands. All the papillary ridges were clearly discernible. The photographer then hooked his camera to a peculiar adjustable tripod and, carefully focusing his lens, took two flash-light pictures of the hand-mark.

“This ought to do.” Dubois was pleased with his find. “It’s the right hand—a clear print—and the guy who made it was standing right behind the dame. … And it’s the newest print in the place.”

“What about this box?” Heath pointed to the black document-box on the table near the overturned lamp.

“Not a mark—wiped clean.”

Dubois began putting away his paraphernalia.

“I say, Captain Dubois,” interposed Vance, “did you take a good look at the inside door-knob of that clothes-press?”

The man swung about abruptly, and gave Vance a glowering look.

“People ain’t in the habit of handling the inside knobs of closet doors. They open and shut closets from the outside.”

Vance raised his eyebrows in simulated astonishment.

“Do they, now, really?—Fancy that! … Still, don’t y’ know, if one were inside the closet, one couldn’t reach the outside knob.”

“The people I know don’t shut themselves in clothes-closets.” Dubois’s tone was ponderously sarcastic.

“You positively amaze me!” declared Vance. “All the people I know are addicted to the habit—a sort of daily pastime, don’t y’ know.”

Markham, always diplomatic, intervened.

“What idea have you about that closet, Vance?”

“Alas! I wish I had one,” was the dolorous answer. “It’s because I can’t, for the life of me, make sense of its neat and orderly appearance that I’m so interested in it. Really, y’ know, it should have been artistically looted.”

Heath was not entirely free from the same vague misgivings that were disturbing Vance, for he turned to Dubois and said:

“You might go over the knob, Captain. As this gentleman says, there’s something funny about the condition of that closet.”

Dubois, silent and surly, went to the closet door and sprayed his yellow powder over the inside knob. When he had blown the loose particles away, he bent over it with his magnifying-glass. At length he straightened up, and gave Vance a look of ill-natured appraisal.

“There’s fresh prints on it, all right,” he grudgingly admitted; “and unless I’m mistaken they were made by the same hand as those on the table. Both thumb-marks are ulnar loops, and the index-fingers are both whorl patterns. … Here, Pete,” he ordered the photographer, “make some shots of that knob.”

When this had been done, Dubois, Bellamy, and the photographer left us.

A few moments later, after an interchange of pleasantries, Inspector Moran also departed. At the door he passed two men in the white uniform of internes, who had come to take away the girl’s body.

Markham and Heath and Vance and I were now alone in the apartment. Dark, low-hanging clouds had drifted across the sun, and the gray spectral light intensified the tragic atmosphere of the rooms. Markham had lighted a cigar, and stood leaning against the piano, looking about him with a disconsolate but determined air. Vance had moved over to one of the pictures on the side wall of the living-room—Boucher’s “La Bergère Endormie,” I think it was—and stood looking at it with cynical contempt.

“Dimpled nudities, gambolling Cupids and woolly clouds for royal cocottes,” he commented. His distaste for all the painting of the French decadence under Louis XV was profound. “One wonders what pictures courtesans hung in their boudoirs before the invention of these amorous eclogues, with their blue verdure and beribboned sheep.”

“I’m more interested at present in what took place in this particular boudoir last night,” retorted Markham impatiently.

“There’s not much doubt about that, sir,” said Heath encouragingly. “And I’ve an idea that when Dubois checks up those finger-prints with our files, we’ll about know who did it.”

Vance turned toward him with a rueful smile.

“You’re so trusting, Sergeant. I, in turn, have an idea that, long before this touchin’ case is clarified, you’ll wish the irascible Captain with the insect-powder had never found those finger-prints.” He made a playful gesture of emphasis. “Permit me to whisper into your ear that the person who left his sign-manuals on yonder rosewood table and cut-glass door-knob had nothing whatever to do with the precipitate demise of the fair Mademoiselle[26] Odell.”

“What is it you suspect?” demanded Markham sharply.

“Not a thing, old dear,” blandly declared Vance. “I’m wandering about in a mental murk as empty of sign-posts as interplanetary space. The jaws of darkness do devour me up; I’m in the dead vast and middle of the night. My mental darkness is Egyptian, Stygian, Cimmerian—I’m in a perfect Erebus of tenebrosity.”

Markham’s jaw tightened in exasperation; he was familiar with this evasive loquacity of Vance’s. Dismissing the subject, he addressed himself to Heath.

“Have you done any questioning of the people in the house here?”

“I talked to Odell’s maid and to the janitor and the switchboard operators, but I didn’t go much into details—I was waiting for you. I’ll say this, though: what they did tell me made my head swim. If they don’t back down on some of their statements, we’re up against it.”

“Let’s have them in now, then,” suggested Markham; “the maid first.” He sat down on the piano-bench with his back to the keyboard.

Heath rose, but instead of going to the door, walked to the oriel window.

“There’s one thing I want to call your attention to, sir, before you interview these people, and that’s the matter of entrances and exits in this apartment.” He drew aside the gold-gauze curtain. “Look at that iron grating. All the windows in this place, including the ones in the bathroom, are equipped with iron bars just like these. It’s only eight or ten feet to the ground here, and whoever built this house wasn’t taking any chances of burglars getting in through the windows.”