- Works, Volume 2
- The Religion of Abraham Lincoln: Correspondence Between General Charles H. T. Collis and Colonel Robert G. Ingersoll
- Col. R.G. Ingersoll's Lectures
- Ingersoll To The Clergy: His Answers To Their Questions And Criticisms
- Take A Road Of Your Own, Or Individuality And Mental Freedom And Hell, Warm Words On The Cheerful And Comforting Doctrine Of Eternal Damnation