s army
again advanced, taking its position on the east bank of the Rio
Grande, and, of course, on the soil of Mexico. Hostilities naturally
followed, and after two battles the President, in his message to
Congress, declared that "American blood has been shed on American
soil." This robust Executive falsehood, with which the slave power
compelled him to face the civilized world, must always hold a very
high rank in the annals of public audacity and crime. It is what
Thomas Carlyle might have styled "the second power of a lie," and
is only rivaled by the parallel falsehood of Congress in declaring
that "by the act of the Republic of Mexico a state of war exists
between that Government and the United States." In the message of
the President referred to, he recommended that a considerable sum
of money be placed at his disposal for the purpose of negotiating
a peace, and it was on the consideration of this message that David
Wilmot fortunately obtained the floor, and moved his memorable
proviso for the interdiction of slavery in any territory which
might be wrested from Mexico by our arms. This was the session of
Congress for 1846-47, and the proposition passed the House with
great unanimity as to the Northern members. At the following
session of Congress, on the 28th of February, 1848, the proviso
again came before the House, and the motion to lay it on the table
failed, all the Whigs and a large majority of the Democrats from
the free States voting in the negative. It passed the House on
the 13th of December following, on a similar division of parties
and sections, but the Senate refused to concur, and the Thirtieth
Congress adjourned without any provisions whatever for the organization
or government of our recently acquired Territories.

It is worth while to notice in passing that on the first introduction
of the Wilmot proviso, in August, 1846, General Cass was decidedly
in its favor, and regretted that it had been talked to death by
the long speech of John Davis; but on the 24th of December, 1847,
he wrote his famous "Nicholson letter," proclaiming his gospel of
"popular sovereignty" in the Territories, which proved the seed-
plot of immeasurable national trouble and disaster. "I am strongly
impressed with the opinion," said he, "that a great change is going
on in the public mind on this subject--in my own mind as well as
others"; and he had before declared, on the 19th of February, that
the passage of the Wil