muscles bore the strain until the
grinding, tearing mass had passed, and he dropped, scratched and
bruised, but otherwise unhurt, to the ground.

As he did so, he heard a faint moan, and hastening in the direction
from whence it came, found Bull-dog, who, unable to spring high enough
to escape the passing rocks, had been swept along and partially buried
under the debris that followed.

"My boy, are you hurt?" asked Houston, bending over him in the
darkness, and removing as fast as possible the mass of crushed and
broken rock under which he lay.

"Not much, I guess," replied the little, familiar voice, in tones that
tried to be brave and cheery, but which quivered with pain, "I tried
to hold on, Mister Houston, but that big rock was a little too much
fer me."

As Houston at last freed him, the little fellow tried to rise, but
sank quickly back, with an involuntary cry:

"I guess I'm done fer--Mister Houston," he gasped faintly, "but I
don't care--if you only--get out safe."

The smoke and gases were now pouring down the shaft, and Houston
realized that there was no time to be lost. Very tenderly he lifted
the little form in his arms, and began, as rapidly as possible, the
descent of the shaft, groping his way amid the rocks, toward the cut
leading to the tunnels, through which he hoped to escape.

The motion roused Bull-dog who had fainted. "Mister Houston," he
cried, "don't mind me--I wanted to save you, and I guess you can make
it yet, if you hurry and don't bother with me; I won't mind bein' left
here, 'cause I'll know then that you're safe."

"Don't you worry, my boy," replied Houston, and his own voice
trembled, "we'll reach daylight all right, but we'll reach it
together; I'll never leave you."

There was no reply except a contented, confiding nestling of the
little head against Houston's shoulder; then, as a second explosion
thundered above them, jarring the foundations of the rocks once more,
he murmured drowsily, "There she goes again," and sank into
unconsciousness.

The smoke was now so stifling that Houston was obliged to go upon his
hands and knees, carrying Bull-dog in one arm; his progress was
necessarily slow, but to his great joy he succeeded in finding the cut
leading to tunnel No. 3; then, to his horror, he discovered that the
entrance was blocked by a mass of earth and loose rock which had caved
in.

Laying Bull-dog carefully down, he examined the obstruction, and
found there was a sm