m assented. "Yet,
on the other hand, it is possible that the fast moving train may have
started the quicksand at some point. The next object that passes over,
even if no heavier than an automobile, may meet with disaster. Mr.
Hazelton and I can soon satisfy ourselves as to whether the roadbed has
sagged at any point along the way. We shall ride nothing heavier than
mustangs."

"There is something in what you say, Mr. Reade. Go ahead. We will wait
until we have your report."

Tom and Harry accordingly mounted, riding off at a trot. Yet at
some sections of the line they rode so slowly, studying the ground
attentively, that it was fully half an hour before they had crossed the
further edge of the Man-killer.

"The engineers are signaling us, Mr. President," reported General
Manager Ellsworth. "They are motioning us to go forward."

Accordingly the party of railway officials entered their automobiles and
started slowly off over the Man-killer.

"Ride back and meet them, Harry," Tom suggested. "Show them that one
point that we noticed."

Hazelton accordingly dug his heels into the flank of his pony, starting
off at a gallop.

Two or three minutes passed. Then Mr. Ellsworth leaped from his seat
in the foremost automobile, standing erect in the car and pointing
excitedly.

"Look there!" he shouted lustily. "What's happening?"

Away off, at the further side of the Man-killer, a horseman had suddenly
ridden into sight from behind a sand pile. His swiftly moving pony
had gotten within three hundred yards of the chief engineer before Tom
looked up to behold the newcomer.

From where the railroad officials watched they could hear nothing,
though they saw a succession of indistinct spittings from something in
the right hand of the horseman.

"It's a revolver the fellow's shooting at Mr. Reade!" gasped
Superintendent Hawkins, leaping into the car beside the general manager.
"Turn your speed on, man--make a lightning lash across the Man-killer!"

Away shot the automobile, not wholly to the liking of two eastern men
who sat in the directors' car.

Tom Reade had realized his danger. Having nothing with which to fight,
Reade had sprung his horse eastward and was racing for life.

The unknown had emptied his weapon, but that did not deter him, for,
continuing his wild pursuit, the stranger could be seen to draw another
automatic revolver.

The bullets striking all about Tom's pony ploughed up the sand.

Within a minu