His foot touched against a good sized fragment of rock left there by one of the masons.
Without delay Harry reached down, picking up the rock, which was rather more than half as large as his head.
Holding this in his right hand Harry advanced with still more confidence, for he felt himself to be armed.

Hazelton had been a clever pitcher in his high school days and knew that he could make this fragment of rock land pretty close to where he wanted it to go.
"Who are you ?" demanded Hazelton, once more, as he stepped cautiously forward.

"No use in your keeping silent, my man.

I see you and know that you're there.

Moreover, I'm going to drag the truth out of you as to what you're doing out here on the wall at this hour of the night---and to-night of all nights." Still no answer; Harry went steadily forward, until he was within a dozen feet of the head of the flattened brute in human guise.