I refer to the outrage he perpetrated upon Hayti, with its six hundred thousand blacks engaged in the great experiment of self-government. Here is a most instructive “antecedent,” revealing beyond question his true nature, and the whole is attested by documentary evidence. Conceiving the idea of annexing Dominica, which is the Spanish part of the island, and shrinking at nothing, he began by seizing the war powers of the Government, in flagrant violation of the Constitution, and then, at great expenditure of money, sent several armed ships of the Navy, including monitors, to maintain the usurper Baez in power, that through him he might obtain the coveted prize. Not content with this audacious dictatorship, he proceeded to strike at the independence of the Black Republic by open menace of war, and all without the sanction of Congress, to which is committed the power to make war. Sailing into the harbor of Port-au-Prince with our most powerful monitor, the Dictator, (properly named for this service,) also the frigate Severn as consort, and other monitors in their train, the Admiral, acting under instructions from Washington, proceeded to the Executive Mansion accompanied by officers of his squadron, and then, pointing to the great war-ships in sight from the windows, dealt his unjust menace, threatening to sink or capture Haytian ships. The President was black, not white. The Admiral would have done no such thing to any white ruler, nor would our country have tolerated such menace from any Government in the world. Here was indignity not only to the Black Republic with its population of six hundred thousand, but to the African race everywhere, and especially in our own country. Nor did it end here. For months the Navy of the United States was kept hovering on the coast, holding that insulted people in constant dread and anxiety, while President Grant was to them like a hawk sailing in the air, ready to swoop upon his prey. FALSE IMPRISONMENT OF AN AMERICAN CITIZEN. This heartless, cruel proceeding found a victim among our white fellow-citizens. An excellent merchant of Connecticut, praised by all who know him, was plunged into prison by Baez, where he was immured because it was feared that on his return to New York he would expose the frauds of the plotters; and this captivity was prolonged with the connivance of two agents of the President, one of whom finds constant favor with him and is part of the military ring immediately about him. That such an outrage could go unpunished shows the little regard of the President for human rights, whether in white or black. HARD TO BEAR THESE OUTRAGES.