The Compromise measures of 1850 were repulsive and disheartening to the antislavery men in the North. And no circumstance connected with them was more discouraging than the change of front made by Daniel Webster--his abandonment of the Wilmot Proviso and his concession to the Southern demand for the extension of slavery into the new territory acquired by the Mexican War. Webster's speech of the 7th of March was answered by Judge Jay in a letter to the _Evening Post_ of March 20th, and was afterwards published as a pamphlet and widely circulated. In this letter Jay recalled the eloquent and positive declaration of Webster made in the Senate on August 10, 1848, after New Mexico and California had been acquired: "My opposition to the increase of slavery in this country, or to the increase of slave representation, is general and universal. It has no reference to the lines of latitude or points of the compass. I shall oppose all such extension at all times and under all circumstances, even against all inducements, against all supposed limitation of great interests, against all combinations, against all compromises." These words were contrasted by Jay with Webster's present excuse for abandoning opposition to the extension of slavery on the ground that the laws of "physical geography" made slavery impossible in the new territory and to forbid its existence there was merely "to re-enact the will of God." "To what," asked Jay, "did this solemn, emphatic, unqualified asservation refer? Did he then know that there was a foot of territory in the United States over which it was morally and physically impossible to extend slavery? Was he promising in these impressive terms to oppose what he was conscious would never be attempted? Did he make this pledge before his country with a mental reservation to unite hereafter with General Cass and the slaveholders in denouncing and scorning the Proviso? Did he mean to deceive his own party? Did he desire to keep up an angry agitation throughout the nation for electioneering purposes, and did he thus intimate his belief in the danger of the extension of slavery and slave representation, when he well knew that the fiat of the Almighty had rendered such extension impossible? Was he then acquainted with the law of physical geography which would render the Proviso 'a re-enactment of the will of God?' And did he purposely conceal the secret of this law in his own breast, when by revealing it he might have stilled the raging billows of popular passion which threatened to ingulf the Union? To suppose all this would be to impute to Mr. Webster a degree of trickery and turpitude rarely paralleled even among politicians. Hence we are bound to assume that the law of nature on which he _now_ relies is a recent discovery, subsequent at least to the 10th August, 1848. It is, however, extraordinary that a gentleman of his acquirements did not sooner