rights established
by the civilized world. General Taylor did not delay his reply. On the
same day he answered the Mexican chief, that inasmuch as he was charged
with the military and not the diplomatic duties of the controversy, he
could not discuss the international question involved in the advance of
the American army, but that he would unhesitatingly continue to occupy
the positions he held at Isabel and opposite Matamoros in spite of all
menaces. The hostile declarations and alternative presented by Ampudia
induced Taylor to order the stringent blockade of the Rio Grande, so as
to stop all supplies for the city, and the naval commander at the Brazos
de Santiago was directed to dispose his forces accordingly. A body of
Texan rangers, under the command of Captain Walker, a tried and daring
soldier of the frontier, was stationed on the road to Point Isabel.
During the night of the 27th and 28th of April, the troops, at the
latter place, consisting chiefly of two companies of artillery, under
the command of Major Monroe, were in momentary expectation of attack in
consequence of rumors from the enemy, for it was known that large bodies
of Mexicans had crossed the river and were striving to interpose
themselves between Isabel and the fort opposite Matamoros in order to
cut off supplies for the garrison. Several teams that departed from the
depot for the fort were forced to return, and, on the morning of the
28th the camp of Walker was surprised on the prairie by a party of bold
rancheros who killed five of our rangers and dispersed the rest, while
the officer of the company and half of his command were absent on
detached service.

By this time the works opposite Matamoros were well advanced, yet, owing
to the peculiar nature of the country and our deficiency in the proper
description of light troops, we were kept in ignorance of the enemy's
movements on the left bank. It was ascertained, however, with sufficient
certainty, that they were continuing to throw considerable forces on the
eastern shore, with the design of attacking our command; and General
Taylor received information, upon which he could rely, that Arista had
prepared to pass the Rio Grande, below Matamoros, in order to effect a
junction with his forces from above. It was not believed, however, that
he would assault the position opposite that city even with four thousand
men, and hence our commander-in-chief supposed that the depot at Isabel
was the object o