Still another night bird screamed, of some species with which Hazelton was wholly unacquainted. The cry was answered by some sort of strange call from the sh.o.r.e.

"It's a fine thing that I'm not superst.i.tious," laughed the young engineer to himself, "or I'd surely feel cold chills chasing each other up and down my spine."

As it was, Harry shivered slightly, though not from fear. With the increasing wind it was growing chilly out there for one who could not warm himself with exercise.

"It's a long time, or it seems so," muttered the young engineer presently.

"Yet I'll wager that Tom is hustling himself and others on the very jump."

Again the call of a night bird, and once more a sound from sh.o.r.e seemed to answer it.

"Real birds?" wondered Hazelton, with a start of sudden curiosity. "Or have I been listening to human signals? If so, the signals can't cover any good or honest purpose."

That train of thought set him to listening more acutely than before. Yet, as no more calls reached his ears the attention of the young engineer soon began to flag.

The monotonous lapping of the waves against the stone wall, the constant splashing of water over the rocks and the steady blowing of the wind all tended to make the watcher feel drowsy.

"What on earth can be keeping good old Tom?" Harry wondered, more than once.

It would have been well, indeed, had Harry kept his eyes turned oftener toward the sh.o.r.e end of the wall. In that case he might more speedily have detected the wriggling, snake-like movement of 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 ma.s.s 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; it's your own fault," Harry Hazelton continued calmly.

"As you won't speak I'm going to crack the nut for myself. Your head will be the nut, and this rock I have in my hand shall be the hammer. I'm going to slam this rock on your head with all the force I've got, and I'm a good, straight thrower."

Yet, though Hazelton spoke with such confidence, he was far from meaning all he said. In the first place, he had no legal right, under the circ.u.mstances, to go as close to murder as it might be for him to throw the rock at the rascal's head. Moreover, Harry would hardly have exercised such a legal right, had he possessed it, without the strongest provocation.

From the black prowler came a sudden, fierce snort. It sounded altogether like defiance.

"Ho---ho! You're finding your voice, are you, my man?" Hazelton jeered.

"Then talk up in time to save yourself!"

Instead the huge black man began to writhe forward.

"Stop that!" ordered Harry dangerously. He did not retreat from the writhing human thing, but he took better aim, noting that the black man was hatless and that his head offered a fair mark. "You're going to get hurt in just about a second more," he added.

Uttering another snort the bulky black sprang to his feet with surprising agility in one of his great size.

Harry now let his right hand fall back quickly. He was poising for the throw in earnest, for there could no longer be any doubt that the stranger was planning a deadly a.s.sault.

"Take it, then, since you want it!" snapped out Harry Hazelton. The fragment of rock left his hand, propelled with force and directed with accurate aim at the negro's face.

But the crafty black dodged just in time, at the same instant throwing up his hands.

Harry gasped as he saw his unknown a.s.sailant deftly catch the rock fragment as though it had been a base ball.

"Ha, ha! Ho, ho!" jeered the black, in a hoa.r.s.e, rumbling voice.

He threw back his hand, gathering impetus for the cast. Hazelton could do nothing but throw himself on the defensive, planning to duplicate the black man's catch.

Then the stone came---but it did not go high, instead, by a jerk of his wrist, the negro hurled it at Harry's right foot.

That granite-like fragment struck Hazelton's foot with full force.

"You---you scoundrel!" groaned Harry, in an all but admiring gasp.

Like a flash he bent over, s.n.a.t.c.hing up the fragment for his own use.

"Now, I'll slam you into the middle of the Gulf of Mexico!" cried the young engineer, vengefully, as he tried to straighten up.

A groan escaped him. His injured foot was paining him more than he had expected.

"Ha, ha! Ho, ho!" harshly jeered this mysterious, evil creature. The black man had halted as Harry prepared to throw, but he showed no sign of hesitation. Though he stood still, he thrust his repulsive, leering face forward, as though to offer that face as the best mark.

Harry found that he could not stand straight---the pain in his injured foot was now too intense.

"Get back with you!" ordered Harry. "Get back if you don't want a heap worse than you gave me."

"Ha, ha! Ho, ho!" came the sneering laugh. Then the stranger reached out his hands as though to seize the youth.

"I guess I'll have to do it---though not because I really want to hurt you!" muttered Harry ruefully.