The letter of Mr. Van Buren was fatal to his prospects. He was caught in the toils prepared by Mr. Calhoun's diplomacy. His disastrous defeat four years before by General Harrison had not injured him within the lines of his own party, or shorn him of his prestige in the nation. He still retained the undiminished confidence of his old adherents in the North, and a large support from the Southern Democracy outside of the States in which Mr. Calhoun's influence was dominant. But the leading Democrats of the South, now inflamed with the fever of annexation, determined upon Van Buren's defeat as soon as his letter opposing the acquisition of Texas appeared. They went to work industriously and skillfully to compass that end. It was not a light task. The force of New York, as has been so frequently and so signally demonstrated, is difficult to overcome in a Democratic National Convention; and New York was not only unanimously, but enthusiastically, for Mr. Van Buren. Hitherto New York and the South had been in alliance, and their joint decrees were the rule of action inside the Democratic party. They were now separated and hostile, and the trial of strength that ensued was one of the most interesting political contests ever witnessed in the country. The Democratic masses had so long followed Southern lead that they were bewildered by this new and unexpected development. From the organization of the Federal Government to that hour, a period of fifty-six years, Mr. Van Buren was the only Northern man whom the Democracy had supported for the Presidency; and Mr. Van Buren had been forced upon the party by General Jackson. His title to his political estate, therefore, came from the South. It remained strong because his supporters believed that Jackson was still behind him. One word from the great chief at the Hermitage would have compelled Mr. Van Buren to retire from the field. But the name of Jackson was powerful with the Democratic masses. Against all the deep plots laid for Van Buren's overthrow, he was still able, when the national convention assembled at Baltimore in May, 1844, to count a majority of the delegates in favor of his nomination. VAN BUREN AND THE TWO-THIRDS RULE.