He stopped short, sucking in his breath with a curious gasping sound, and felt eagerly for his magnifying glass. For his eye had been caught by the slightest of marks on the fingertips of the dead woman. Then he looked at her lips, and stooping, sniffed vigorously. For a moment he stood very still, then with a sort of new dignity rose and faced round on Mr. Montelet, who was watching him with intense eagerness written upon his countenance. "Do you know if Lady Montelet had anything to drink previous to her retirement to this room?" he said abruptly. It was Mademoiselle Vaudrot who interposed a reply. "But, yes, m'sieur; she had a cup of black coffee, so that she should keep awake, and it was I that brought it to her with my own hands. And my dear, dear lady put it down on this little table. See, this one"--pointing to a little Persian stool that stood near the left-hand column--"then she kissed me good-night and locked herself in." "Locked herself in!" rapped out Cleek. "How, then, was this door opened in the morning?" "I opened it," said young Montelet in low tones. "I have a duplicate key. When we knocked and knocked and called this morning and could get no answer, I remembered that my father had given me a key to be used in case of accidents, years ago. No one knew I had it. And then I wired for Mr. Narkom." "I see," said Cleek, stroking his chin pensively. Then he added suddenly: "I've got a book down in the car that I believe might be a bit of a help. It's a new detective story; nothing like a good story to refresh one's mind. If you would get it; here's the title, Mr. Narkom, and exactly where I left it. Run down and get it, there's a good chap." The "good chap" was out of the room before Mr. Montelet could voice the protest which shone so plainly in his eyes. "I think, somehow, that we've all been on a wrong tack. What if the old lady--her ladyship--took out the stone, and when the pain at her heart caught her, let the blessed thing drop? Anyhow, I'd like to pull up the rugs--if you've no objection, Miss Gwynne." "Not in the slightest," answered that lady quickly. "I'll help you if you like, and so shall Miss Vaudrot. We'll all search." Another minute saw the four people on hands and knees, searching and pulling at the rugs and draperies; and it was thus vainly employed that Mr. Narkom, flushed and excited, found them when he returned. "Did you find it, Mr. Narkom?" inquired Cleek, jumping briskly to his feet, his example followed by the other three. "Rather! Just as you said." "Oh, well, never mind about it now. Shan't want it, after all. I've just struck another idea." And he crossed over to the marble pedestal. "What's that?" asked young Montelet, interestedly as he followed Cleek's beckoning hand. "I forgot I hadn't examined the blessed pedestal. A ducat to a guinea that it's hollow, and the beastly stone has slipped down."