f the big negro moving
toward him.

With great caution the huge prowler came onward, raising his head a few
inches every now and then and listening. The black man's nostrils moved
feverishly. He was using them, as a dog would have done, to scent any
signs of alarm on the part of the human quarry that he was after.

At last Harry Hazelton turned sharply, for his own ears were attuned to
the stillnesses of the western forests and his hearing was unusually acute.
He had just heard a sound on the wall, not far away. Instantly the young
engineer was on the alert.

Then his eyes, piercing the darkness, made out the crawling, dark form,
which did not appear to be more than fifty feet away from him.

For a second or two Harry stared. But he knew there could be no snake as
broad as this crawling figure appeared to be.

"Who's there?" Hazelton called quickly.

The writhing mass became still, flattening itself against the bed of rock.
Hazelton was not to be deceived, however.

"Who's there?" Harry repeated. "You had better talk up, my man!"

Still no sound. Harry started forward to investigate. 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. Hazelton could now
see every line of his adversary plainly, though he could not make out the
fellow's face.

"You'd better get up and talk," warned Harry, poising the rock fragment
for a throw. "If you don't you'll cast all the more suspicion upon
yourself. For the last time, my man, who are you and what are you doing
here?"

The huge black figure might have been a log for all the answer that came
forth.

"All right, then;