The collection consists of letters written to Charles Gilpin between the 1830s to 1874, many from British politicians, social reformers, and abolitionists. Topics include capital punishment, Hungarian exiles, parliamentary elections, foreign relations, prisons, Poor laws, and the abolition of slavery. Quakers are prominent, but the Society of Friends was not discussed. The content is varied and represents his social and political interests. The publishing business rarely appears in the correspondence. Correspondents include Elihu Burritt, William Lloyd Garrison, Joseph John Gurney, Samuel Gurney, Victor Hugo, Charles Mackay, Eliza Meteyard, and Grace Greenwood (Sara Jane Lippincott).