""A Popular Essay On Subjects Of Penal Law, And On Uninterrupted Solitary Confinement At Labor"" is a book written by Francis Lieber in 1838. The book discusses various topics related to penal law, including the history and philosophy of punishment, the principles of criminal justice, and the role of prisons in society. One of the main focuses of the book is on the practice of uninterrupted solitary confinement at labor, which Lieber argues is a more...