CHAPTER IV.
Review (_continued_) .-- Relations with Mexico .-- General Taylor marches his Army to the Rio Grande .-- First Encounter with the Mexican Army .-- Excitement in the United States .-- Congress declares War against Mexico .-- Ill Temper of the Whigs .-- Defeat of the Democrats in the Congressional Elections of 1846 .-- Policy of Mr.
Polk in Regard to Acquisition of Territory from Mexico .-- Three- Million Bill .-- The Famous Anti-slavery Proviso moved by David Wilmot .-- John Quincy Adams .-- His Public Service .-- Robert C.Winthrop chosen Speaker .-- Treaty of Guadalupe Hidalgo .-- Presidential Election of 1848 .-- Effort of the Administration to make a Democratic Hero out of the Mexican War .-- Thomas H.Benton for Lieutenant-General.
-- Bill defeated .-- Nomination of General Taylor for the Presidency by the Whigs .-- Nomination of General Cass by the Democratic Party.
-- Van Buren refuses to support him .-- Democratic Bolt in New York.
-- Buffalo Convention and the Organization of the Free-soil Party.
-- Nomination of Van Buren and Charles Francis Adams .-- Mr.Clay's Discontent .-- Mr.Webster's Speech at Marshfield .-- General Taylor elected .-- The Barnburners of New York .-- Character and Public Services of Mr.Van Buren.
By a suggestive coincidence, the practical abandonment of the line of 54 deg.

40' by the administration was contemporaneous with the outbreak of the Mexican war.

The modified resolution of notice to Great Britain was finally passed in both branches of Congress on the 23d of April, and on the succeeding day the first blood was shed in that contest between the two Republics which was destined to work such important results in the future and fortunes of both.
The army of occupation in Texas, commanded by General Zachary Taylor, had, during the preceding winter, been moving westward with the view of encamping in the valley of the Rio Grande.

On the 28th of March General Tyler took up his position on the banks of the river, opposite Matamoros, and strengthened himself by the erection field-works.

General Ampudia, in command of the Mexican army stationed at Matamoros, was highly excited by the arrival of the American army, and on the 12th of April notified General Taylor to break up his camp within twenty-four hours, and to retire beyond the Nueces River.