"Now, you know, this is really about the most serious and important thing I've heard, so far," he said, when Mr. Cazalette had finished. "Just let's sum it up. Salter Quick is murdered in a strange and lonely place. Not for his goods, for all his money and his valuables--not inconsiderable--are found on him. But the murderer was in search of something that he believed to be on Salter Quick, for he thoroughly searched his clothing, slashed its linings, turned his pockets out--and probably, no, we may safely say certainly, failed in his search. He did not get what he was after--any more than his fellow-murderer who slew Noah Quick, some hundreds of miles away from here, about the very same time, got what he was after. But now comes in Mr. Cazalette. Mr. Cazalette, inadvertently, never thinking what he was doing, draws public attention to certain marks and scratches, evidently made on purpose, in Salter Quick's tobacco-box. Do you see my point, gentlemen? The murderer hears of this and says to himself, 'That box is the thing I want!' So--he appropriates it, at the inquest! But even then, so faint and almost illegible are the marks within the lid, he doesn't find exactly what he wants. But he knows that Mr. Cazalette was going to submit his photograph to an enlarging process, which would make the marks clearer; he also knows Mr. Cazalette's habits (a highly significant fact!) so he sets himself to steal Mr. Cazalette's pocket-book, theorizing that Mr. Cazalette probably has a copy of the enlarged photograph within it. And, this morning, while Mr. Cazalette is bathing, he gets it! Gentlemen!--what does this show? One thing as a certainty--the murderer is close at hand!" There was a dead silence--broken at last by a querulous murmur from Mr. Cazalette himself. "Ye may be as sure o' that, my man, as that Arthur's Seat o'erlooks Edinbro'!" he said. "I wish I was as sure o' his identity!" "Well, we know something that's gradually bringing us toward establishing that," remarked Scarterfield. "Let me see that photograph again, if you please." The rest of us watched Scarterfield as he studied the thing over which Mr. Cazalette and I had exercised our brains in the half-hour before dinner. He seemed to get no more information from a long perusal of it than we had got, and he finally threw it away from him across the table, with a muttered exclamation which confessed discomfiture. Miss Raven picked up the photograph. "Aye!" mumbled Mr. Cazalette. "Let the lassie look at it! Maybe a woman's brains is more use than a man's whiles." "Often!" said the detective. "And if Miss Raven can make anything of that----" I saw that Miss Raven was already wishful to speak, and I hastened to encourage her by throwing a word to Scarterfield. "You'd be infinitely obliged to her, I'm sure," I put in. "It would be a help?" "No slight one!" said he. "There's something in that diagram. But--what?"