The prospect was dark for the antislavery cause in 1850. Its friends had increased steadily in numbers and in earnestness. But the Slave Power had mustered all its forces in an aggressive campaign which aimed to make slavery a national instead of a local institution, to introduce it into territory hitherto free, and to browbeat the North into submission to every demand of the slaveholder. The compromise measures adopted this year in Congress—above all, the Fugitive-Slave Law—marked the successful advance of arrogant Southern dictation. In the North, the dislike of antislavery men and the willingness to satisfy the South at the expense of conscience was expressed in such scenes as the attack of the Rynders mob on the meeting of the American Antislavery Society in New York and the passive attitude towards it adopted by the authorities. Although the plan of putting down the abolitionists by force had proved impracticable, no efforts were spared to make their lives uncomfortable by the attacks of the press and by the pressure of social disapproval. "Our politicians," wrote Jay to Charles Sumner, "may pride themselves on their adroitness in pandering to popular prejudices, and in acquiring power and influence by seasonable changes of opinion and conduct. But a day is coming when their motives and actions will be judged by a very different tribunal than public opinion, and when a single act of benevolence, a single sacrifice of personal consideration to the cause of truth, will outweigh a whole life of obsequiousness and political trickery.

"The truths we advocate are unpalatable to the two extremes of society. We shock the coarse, vulgar prejudices of the rabble, while the disinterested benevolence we profess is to them an enigma to be solved only by the imputation of fanaticism. At the same time we disturb the tranquil consciences of the rich, thwart the calculations of politicans, and interrupt the harmony subsisting between our merchants and their Southern customers. Hence the upper classes look upon us as impertinent and exceedingly ungenteel, and unfit to move in the higher circles. I cannot tell how far your personal experience coincides with mine, but I know whereof I affirm. I have advanced no ultra-fanatical doctrines in politics or religion. On the subject of slavery I have but reiterated the opinions of many of the best and greatest men in England and in our own country. I have advocated no congressional action except such as Mr. Webster, in his better days, pronounced constitutional, and I have condemned all forcible resistance to the Fugitive-Slave Law. Yet solely on account of my antislavery efforts, I find myself nearly insulated in society."

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 become acquainted with 'this law of physical geography—the law of the formation of the earth, that settles forever, beyond all terms of human enactment, that slavery cannot exist in California or New Mexico.' It is to be regretted that Mr. Webster did not condescend to demonstrate the existence of this law and to explain the mode of its operation. He indeed tells us that our new territories are 'Asiatic in their formation and scenery'; but this fact does not prove his law, since slavery has existed for ages amid the scenery of Asia; it exists in the deserts of Africa, has existed in every country of Europe, and now exists in the frozen regions of Russia. This law, moreover, must have been enacted by the Creator since 1824, or its operation must have been suspended in deference to the Spanish government; for under that government negro slavery did exist in California and New Mexico, and it ceased in 1824, not by the 'law of physical geography,' but by a Mexican edict. Thousands of slaves are employed in the mines of Brazil, and Mr. Webster does not explain how his law forbids their employment in the mines of California....

"He pays a sorry compliment to the common sense of the people in offering to them at the eleventh hour a new and unheard-of law of 'physical geography,' together with the 'Asiatic scenery and formation' of the conquered territories, as an excuse for violating the faith he had plighted in behalf of the Proviso. He has shocked the moral sense of a large portion of the community by giving in advance his sanction to the Fugitive-Slave Law, which makes the liberty or bondage of a citizen depend on the affidavit of a slaveholder and the judgment of a post-master—a law which converts sympathy for guiltless misery into crime, and threatens to tenant our jails with our most estimable men and women. But Mr. Webster underrates the intelligence and sensibilities of the masses. Relying on the Southern affinities of our commercial cities, on the subserviency of politicians, on the discipline of party, and on his own great influence, Mr. Webster looks down upon the people; but the time is probably not far distant when the people will cease to look up to him. Parties will accept of any leaders who can acquire for them the spoils of the day, but in the political history of our country the people have never placed their affections upon any man in whose stability and consistency they did not confide."

To give such assistance as he could to a fugitive slave had always been regarded by Judge Jay as a duty. "The slaveholders," he had written, "with their accustomed impudence and mendacity, apply the term theft to the humane and Christian efforts to assist a slave in escaping from his home of bondage. In their sense of the expression, I glory in being a slave-stealer, and I inculcate upon my children the duty, the Christian duty, of this kind of theft." He had sheltered and aided many runaways at his home at Bedford, and his will contained a bequest of a thousand dollars to be used for this purpose. His son John gave his services as a lawyer constantly and successfully to prevent the return of fugitive slaves.

When the Fugitive-Slave Bill became a law Judge Jay was applied to by many individuals, societies, and periodicals to give his views concerning it. "The law," he said in a private letter, "is an outrage upon the Constitution of our country and the precepts of our religion. It is a burlesque on justice and on all the acknowledged rules of evidence in the trial of issues. The demand it makes upon individual citizens to aid in hunting and enslaving their fellow-men is diabolical. I have made up my mind to suffer imprisonment and the spoiling of my goods rather than hazard my soul by rendering any active obedience to this sinful law. It is horrible that so many of our fashionable cotton divines are now preaching up the supremacy of human law and virtually dethroning Him whose ambassadors they profess to be."

"In my opinion, every Northern slave-catcher is a base man, and every lawyer who takes reward against the innocent is a disgrace to a noble profession. I myself shall offer no forcible resistance against the execution of this most wicked law, but I trust that, through the grace of God, I would go to the scaffold sooner than obey it."