Holmes had stepped across, had lit the candle, and was passing it backward and forward across the windowpanes. Then he peered into the darkness, blew the candle out, and threw it on the floor.

“I rather think that will be helpful,” said he. He came over and stood in deep thought while the two professionals were examining the body. “You say that three people came out from the flat while you were waiting downstairs,” said he at last. “Did you observe them closely?”

“Yes, I did.”

“Was there a fellow about thirty, black-bearded, dark, of middle size?”

“Yes; he was the last to pass me.”

“That is your man, I fancy. I can give you his description, and we have a very excellent outline of his footmark. That should be enough for you.”