[P-Marlowe]

The famous atheist Robert Ingersoll was an abolitionist.

Perhaps you have him mixed up with his father. His father, John Ingersoll, was a famous abolitionist. His Father was also a preacher, so I suspect that any abolitionist ideas he got came from his father's pulpit. I can't seem to find any abolitionist writings by Robert Ingersoll. Perhaps you have some?

[Virginia-American]

Essay on Robt. Ingersoll by M. M. O'Hair. She says he got abolitionism from his parents, but was an SOB on most other issues.

another essay. Google gets a lot of hits