"How did he get the dagger? He didn't steal it, because the evening it was stolen he was safe in the hoosgow."
"Correct, Krech, absolutely correct." The detective was intently studying the brass lock of the door through his powerful glass. "Now you've started thinking, persevere! If Maxon committed the murder but didn't steal the knife, what's the answer?"
"An accomplice!" cried Krech. "A whole gang, perhaps!"
"Oh, don't be extravagant. One accomplice will do for the time being." Creighton dropped to his knees and transferred his interest to the flooring of the piazza outside the window and the carpet within. "_By golly!_"
The phrase fairly exploded from his lips. Krech, abandoning his cogitations, came quickly to his side, eager to learn what this exclamation portended.
Creighton, with his habitual care to miss nothing, had not contented himself with exploring the surface of the veranda or the surface of the heavy gray carpet that covered the floor of the room from edge to edge. That finished, he had thrust his fingers between the carpet and the wood of the window-sill, holding it back with one hand while he passed his magnifying glass over the accumulation of dust and dirt and sweepings that lay in the crack. His pains were rewarded. A tiny scrap of something that glittered in its nest of dirt caught his eye, but it was not until it lay on the tip of one finger beneath his glass that he realized the importance of his treasure trove. It was then he exclaimed.
"What is it?" asked Krech, craning for a better look.
"See for yourself!" Very carefully the detective pushed the object from his finger on to one of his friend's. "Don't drop it. What do _you_ think it is? Here--take the glass."
"A chip of metal, I should say. Steel. Blue steel."
"Blue steel! Where have you seen blue steel before to-day?"
"Right. Did you notice the nick in it near the point?"
"N-no. They wouldn't let me really look at it."
"Well, there was one! And this piece will fit that nick, or I'm a dumb-bell!" His eyes were dancing with delight. "Know what this means?"
"Y-yes. When the fellow slipped back the catch of this window he nicked the blade. Probably never noticed it. This piece fell to the floor and has been there ever since."