Dickinson's remarkable public career began in 1856 when William Lloyd Garrison published in the Liberator a letter young Dickinson had written protesting the apparent indifference and political apathy of northerners to the tarring and feathering of a Kentucky schoolteacher who had criticized slavery. Four years later Dickinson delivered her first public address, "The Rights and Wrongs of Women," at Clarkson Hall in Philadelphia. Her extemporaneous, sarcastic response to a man's suggestion that women were suited only for the role of homemaker drew a favorable response from the crowd. That day she made the acquaintance of social reformers Ellwood Longshore and Dr. Hannah Longshore, who encouraged Dickinson to speak out on the subjects of woman's rights and antislavery before local audiences. When she spoke before the Philadelphia Anti-Slavery Society in 1860, she received favorable and widespread reviews by the press. Soon thereafter Lucretia Mott introduced her to an audience of 800 at Concert Hall in Philadelphia, where she spoke for two hours on woman's rights.
Kathleen C. Berkeley, "Dickinson, Anna Elizabeth," American National Biography Online, February 2000, http://www.anb.org/articles/15/15-00177.html.