For the first and only time in our political history, an administration conducting a war victorious at every step, steadily lost ground in the country. The House of Representatives which declared war on the 11th of May, 1846, was Democratic by a large majority. The House, elected in the ensuing autumn, amid the resounding acclamations of Taylor's memorable victory at Monterey, had a decided Whig majority. This political reverse was due to three causes,--the enactment of the tariff of 1846, which offended the manufacturing interest of the country; the receding of the administration on the Oregon question, which embarrassed the position and wounded the pride of the Northern Democrats; and the wide-spread apprehension that the war was undertaken for the purpose of extending and perpetuating slavery. The almost unanimous Southern vote for the hasty surrender of the line of 54 deg. 40', on which so much had been staked in the Presidential campaign, gave the Whigs an advantage in the popular canvass. The contrast between the boldness with which the Polk administration had marched our army upon the territory claimed by Mexico, and the prudence with which it had retreated from a contest with Great Britain, after all our antecedent boasting, exposed the Democrats to merciless ridicule. Clever speakers who were numerous in the Whig party at that day did not fail to see and seize their advantage. The Mexican war had scarcely begun when the President justified the popular suspicion by making known to Congress that one of its objects was to be the acquisition of territory beyond the Rio Grande. Perhaps it would be fairer to say that he expected such acquisition to be one of its results. He ably vindicated the policy of marching a military force into the territory between the Nueces and the Rio Grande, by the fact that he was memorialized to do so by the still existing Congress of Texas, on the urgent plea that Mexico was preparing to move upon the territory with a view to its recapture. In this Congress of Texas, the same body that completed the annexation, there were representatives from the territory in dispute beyond the Nueces; and the President felt that they were in an eminent degree entitled to the protection of our government. Events were so hurried that in three months from the formal declaration of war, and before any victory of decisive significance had been achieved, the President sent a special message to Congress, in which he suggested that "the chief obstacle to be surmounted in securing peace would be the adjustment of a boundary that would prove satisfactory and convenient to both republics." He admitted that we ought to pay a fair equivalent for any concessions which might be made by Mexico, and asked that a sum of money should be placed in his hands to be paid to Mexico immediately upon the ratification of a treaty of peace. As a precedent for this unusual request, the President cited the example of Mr. Jefferson in asking