The next struggle in which they engaged for political aggrandizement, was the Mexican war. It could, indeed, hardly be called a struggle,--the north so readily and ignominiously yielded. They wanted more territory. Texas, already gravid with future slave states, was not sufficient. And though it was yet somewhat uncertain whether Congress would not interdict the extension of slavery over that country, even should they conquer it; still, as they had always triumphed in their contests with us, they assumed the risk, and trusted to their future prowess and skill to monopolize the plunder. The territory was conquered; and then, perhaps, the most important question arose which has ever come before this country since the Declaration of Independence. The most momentous consequences were suspended on the decision of this question. We had, as it were, a creative power put into our hands. We had the shaping of the destinies of half a continent intrusted to our keeping. Our authority once exercised, the act would be irrevocable, and the doom of all that region would be fixed, as by a decree of Omnipotence. When God gives to the world a generation of children, and they are ruined through parental neglect, he gives another generation, that another trial may be made. But if we once admit slavery into those immense regions, comprising all the unsettled residue of this continent, God will give us no new continent on which the error may be retrieved. Now, on this great question, what has been done? I grieve to say that I fear the battle has been lost. If not lost, nothing can save it but a vigor and an energy on the part of the north, such as they have not lately put forth. So far as legislation is concerned, the whole battle field is in possession of the enemy. Let me read a passage from one of the acts of the last session of Congress, which settles this fact. By the law for creating the territorial government of New Mexico, it is expressly provided,-- “That when admitted as a state, the said territory, or any portion of the same, shall be received into the Union, WITH OR WITHOUT SLAVERY, as their constitution may prescribe at the time of their admission.”