"Well, you see he might have fancied--as I do--that a discovery of the papers may lead to the implication of the husband in this matter." "You think Brand killed his wife?" "No. It was a woman, and I believe Mrs. Fane for choice. But Brand may have loved Mrs. Fane and so the whole trouble may have arisen. I guess Mrs. Brand was glad to see her husband start for Australia, for I'm certain from this message that he threatened to kill her. Bocaros having got the money, and thinking of his living near Ajax Villa, might have torn it up. Now Mrs. Brand if she was murdered--as she was--wished the assassin to be brought to justice. The concealed papers will give the clue." Tracey rose and looked round the room. "Where the deuce are they, anyhow?" "Under the coffee stain," said Arnold, not rising, "and I think instead of hunting we had better reason the matter out. A coffee-stain would naturally be on a table-cloth." "A white dinner table-cloth," assented Tracey sitting, "but she couldn't conceal papers there. I've lifted every cloth in the house white and otherwise--there's white ones here as you see--but I couldn't find anything. You needn't look at the roof, Calvert. The coffee-stain won't be there." "No," said Arnold looking down, "it may be on the wall. "Not unless Brand threw a cup at her head." Tracey glanced round the walls; they were all spotless and white. "Maybe on the carpet." "Have you examined the carpets?" "I haven't lifted them, if that's what you mean." "Then I dare say the papers are hidden under the carpet of this room." "Why here? It may be the dining-room, or----" "No," replied Arnold rising, "a coffee-stain would show only on a white carpet, and it was the peculiar furnishing of this room which gave her the idea of the hiding-place"--he looked carefully at the floor--"but I can't see any stain." "A woman like Mrs. Brand," suggested Tracey, "proud of the smartness of this room, would hide any stain. Let's move all mats and furniture." Calvert thought this was a good suggestion, and they set to work. The piano was moved, but needless to say nothing was found there. The various draperies were pulled aside. A book-case was shifted. All the mats were flung out of the door. When they moved everything, still no stain appeared. Then they came to a thick wooden pedestal bearing a plaster-of-paris Venus. It was screwed to the floor near the window and surrounded by mats. "This is the last chance," said Tracey. A few minutes' work sufficed to overturn the column. There, beneath it, and concealed by the base, was the coffee-stain spoiling the purity of the carpet. Tracey produced a large knife, and ripped up the carpet. Thrusting in his hand he pulled out a slim green book rather large in size, and thereon in gilt letters were the words "My Diary!" "This solves the mystery," said Tracey quietly, "now we'll learn the truth." CHAPTER XVII THE PROFESSOR'S TRUMP CARD