meal, just before dark, Captain Foster remarked:

"I've posted a corporal and a guard to see that none of the boats leave
shore until they've been found to contain no freight that looks like
munitions of war. To my surprise none of the Mexicans showed the
slightest interest in my doings. It begins to look as though they have
no intention of trying to ferry arms over the frontier at present."

"Are there any steam craft at this point, sir?" inquired Lieutenant Hal.

"Nothing of the sort, Mr. Overton."

"Then, if the Mexicans do plan to get any war supplies over the
frontier, don't you imagine that they have arranged for a launch or a
tug to drop down the river, or come up the stream, from some other
point?"

"That's worth thinking of," muttered the captain, looking thoughtful.

"A boat engaged in such secret work would probably also take the risk of
running without lights."

"But a steamer would be bound to make noise enough to give us warning
when she attempted to come in toward the shore," pursued Captain Foster.

"That, sir, will depend on how far apart our guards are to-night, or on
such other night as the Mexicans may make the attempt."

"Now that our troops are here they may make no attempt," hinted Noll.

"They will if they dare," replied Captain Foster. "If there are six
hundred rifles in Guarez's barn, and more elsewhere, then there must be
a lot of Mexicans on the other side waiting impatiently for the supplies
to reach them. Your suggestion, Mr. Overton, about a steamer, is one
that must be kept in mind."

After some thought Captain Foster wrote a telegram, entrusting it to a
corporal to take over to the village.

Hal was then directed to take sixty men and to dispose of them in
suitable spots along the water-front. Fifty men were to be used for this
purpose. A corporal and three men would then patrol along the easterly
end of the line, Hal and the few remaining men of his command patroling
the western end of the line. Either patrol would be quick to respond to
any shot from a sentry.

"This is an exceedingly responsible task, Mr. Overton," Captain Foster
informed the young officer. "If you fail at some point, then arms enough
to equip a brigade of Mexican rebels may cross the river to-night."

"I shall keep every sense on the alert, sir."

Noll was given command of the camp. Captain Foster, now thoroughly
fagged, turned in for a few hours' sleep, after leaving orders to be
called at eleven o'