his hands.

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

"Ha, ha! Ho, ho!" jeered the black, in a hoarse, 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, snatching 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.