"Throw it through a bookcase door," was Ashton-Kirk's astonishing reply.
Fuller stood amazed.
"What?" gasped he.
"Throw it through a bookcase door," repeated the secret agent, busy with his lens.
Fuller stood a moment, hesitating; the other arose impatiently, took the heavy paper-weight from him and sent it crashing through the door of the nearest case. The glass splintered and fell jingling to the floor; Ashton-Kirk selected two small pieces and handed them to Fuller.
"In the kitchen you will find hot water and soap; wash and dry these carefully."
The assistant went hastily, and while he was gone, Ashton-Kirk bent once more over the broken knob. With the thin blade of a pocket-knife he picked at the fragment of dried blood; finally he worked it loose and caught it upon a card as it fell. Carrying this to a small table above which hung a light, he examined it carefully. Then to Fuller, as the latter returned, he said:
"Are they ready?"
"All ready," replied Fuller, and he placed the two pieces of glass ready to his employer's hand.
Once more Ashton-Kirk looked at the blood clot; selecting that portion of it which appeared to be thickest he pressed the back of the knife blade carefully against it; then taking it up with the tip of his fingers he carefully broke it in two at the exact place. Sharply he brought the pieces under the light; two crimson, shining spots of uncongealed blood showed within the outer crust.