The President, without the authority or knowledge of Congress, ordered General Taylor to march to the Rio Grande and maintain it as the southern line of Texas. This precipitated the battles of Palo Alto and Resaca de la Palma, in which Taylor defeated the Mexicans. The Democratic Congress then prefaced a bill providing for the national defence by declaring that “we are at war by the act of Mexico.” The purpose of the Mexican war was very freely and severely criticised by a large portion of the people and by many of the ablest men of the nation. The Whigs in Congress were willing to vote for all needed appropriations for the support of the army, but a few members of the House, with the late John Strohm, of Pennsylvania, as the leader, after unsuccessfully struggling to strike out the declaration that “we were at war by the act of Mexico,” refused to vote for the army appropriation; and Corwin, of Ohio, made the ablest speech that ever was delivered in the Senate, with the single exception of Webster’s reply to Hayne, against the Mexican war and against appropriating money for its prosecution. [Illustration: ZACHARY TAYLOR] The certainty that the administration would acquire a large portion of Mexican territory for the purpose of creating new Slave States gave dignity and importance to the slavery agitation that it never before attained, and in the fall elections of 1846 the Whigs carried the popular branch of Congress by a decided majority. The repeal of the protective tariff of 1842 and the substitution of the revenue tariff of 1846 contributed considerably to the Democratic disaster, and the war was finally prosecuted by the administration with an adverse House, although willing to furnish all appropriations necessary to support the armies in the field.