clock.

"You will find me prowling about your lines from midnight on, Mr.
Overton," was the captain's last word before turning in. "It is now
nearly dark, so I suggest that you march your men without any
unnecessary delay."

Two minutes later Lieutenant Hal was marching his command from camp. He
did not take his column through the village. Instead, he marched it to
the eastward, then over to the river bank.

Posting his fifty sentries about three hundred feet apart the Army boy
thus covered a stretch of water-front some three miles in length, the
village's strip of river front being nearly at the middle of this line.
Corporal Smith's patrol was at the westerly end of the line. Hal himself
headed the patrol at that end. The sentries were instructed to conceal
themselves, in order to catch, if possible, any band of rebel smugglers
in the act of loading war munitions on a craft.

"Nothing will come of it to-night," muttered Hal to himself, after he
had placed his men. "The Mexicans here know that there are troops on the
spot. If they were going to ship guns to-night they'd be sure to do it
at some point ten or twenty miles from here. This is a job for a whole
brigade of infantry. A regiment of cavalry could do more than three
regiments of infantry on this work."

But Hal knew that the only two troops of cavalry so far ordered to
frontier patrol were two troops at least a hundred miles to the
westward. As yet Uncle Sam's soldiers were posted only at particular
points known to harbor resolute Mexican rebels.

"The fish can get through the net without the least trouble," thought
the young officer.

It was still, dark and quiet out here on the river front. There were no
lights, and seemingly none astir except the soldiers.

"Corporal, you stay with the patrol. I'm going to do a little exploring
on my own account," said Lieutenant Hal, after another hour had passed.

"Very good, sir," replied Corporal Dent.

Hal had no very definite objective when he started off eastward by
himself. He had left his sword behind in camp, but his revolver rested
in its holster on his right hip.

The more Lieutenant Hal thought about it the less he was inclined to
feel that there was any likelihood that Mexicans would attempt to-night
to cross the river anywhere in the neighborhood of United States troops.

"The leaders among these fellows all know that they're being watched,"
thought Hal, "and they won't take chances when success me