"Perhaps you had better be a little more explicit," he said.
"Time enough for that, presently. My first discovery was in connection with the dining-room fireplace. I fancy you know what I mean. The next item was connected with the stairs. You murderous dog, so that was the trap you laid for me. I was not to go until you had seen me again. I was to stay for the sake of your sister. Well, I am glad that I obeyed now. But my little discoveries did not end here. Mrs. Richford, what is this?"
Berrington held out a strip of soiled linen and Beatrice took it in her hand.
"It looks like a collar," she said. "It is a collar. If you have made a discovery, Colonel Berrington, I have made another. This collar belongs to my father; I marked it for him in some new ink that does not want heating. Melanyl, I think they call it. It was one of a set of a dozen collars and I marked them all, the day of that fatal dinner party. You see that, as my father had had no valet of late----"
"You acted in his stead," Berrington said eagerly; "when did you mark this?"
"About half-past four on the day of the dinner party."
"Not long before your father went up to dress for dinner, I suppose?"
"Yes, it would be about that time. After marking the collars that had just come from the makers, I placed them in father's wardrobe in his bedroom."
"Then this is the very collar that he wore for the dinner party," Berrington cried; "the very collar that he was wearing at the time he disappeared. And the same collar I found not an hour ago in Mr. Sartoris's dining-room. Not in the dining-room proper, but in a kind of vault under the floor. What is the explanation of this, I wonder?"
"If you are so cursedly clever," Sartoris sneered, "you had better find out for yourself. Get him out of the way, get both of them out of the way, get the diamonds, and let us disappear. The game is up so far as England is concerned. Get him out of the way."
Sartoris's voice had risen to a wild scream. He sent his chair rapidly across the room in the direction of the door. Berrington pulled him up sharp.
"No tricks," he said sternly. "Now none of those electrical contrivances of yours. If you move so much as an inch further I'll shoot you like a dog."