Lovers of liberty on both sides of the Atlantic were brought into closer fellowship by books singularly free from anti-British prejudice; but he was so thoroughly American that he declared, even in London, that the true aristocracy must be founded on merit, for "Birth has been tried and failed." This lecture was often repeated, and was finally given in 1881 as his last word in public. Introspective and retiring habits kept him for some time from engaging actively in the reforms which were in full blast about 1840; but Lowell said he was "the sleeping partner who has supplied a great part of their capital." His words about slavery were few and cold before the Fugitive Slave Bill was passed in 1850. Indignation at this command to kidnap made him publicly advise his neighbours to break the wicked law. He spoke in support of a Free Soil candidate in 1852, and for the Republican party in 1854; but John Brown called out much more of his praise than any other abolitionist. The attempt of the Garrisonians to persuade the North to suffer the seceders to depart in peace won his active aid; but the speech which he tried to deliver on their platform, early in 1861, was made inaudible by a mob of enthusiasts for maintaining the Union by war. He rejoiced in emancipation; but it was not achieved until he had lost much of his mental vigour. This, in fact, was at its height between 1840 and 1850. His last volumes were in great part made up of his earliest writings. There was no change in his opinions; and his address in 1838 was fully approved by him when he re-read it shortly before his death.