In 1843, her interest in the anti-slavery movement was aroused by a visit from Boston philanthropist Samuel May. In 1846 she attended a meeting which was addressed by prominent abolitionist William Lloyd Garrison and Frederick Douglass, who had escaped from slavery in 1838. She contributed to fund-raising efforts in the abolitionist cause and maintained an interest in this for the next twenty years. Her brothers William, Philip and Russell and her sister Anna were also active in this campaign. In 1851 the return of a fugitive slave from Boston back to the southern states caused her to say of the Fugitive Slave Law of 1850 that the United States had "committed an atrocious act ... against humanity, against itself, against God." This event caused her to concentrate on her educational work.