Lyman Gibson Bennett enlisted in the 36th Illinois Infantry in 1861. Prior to the War he trained as a surveyor and civil engineer, working for the railroad. The military utilized Bennett’s skills as a cartographer, and assigned him to survey battlefields, road systems, and fortifications. Bennett’s diaries document his daily duties as both a soldier and an engineer for the military. His regiment participated in the Battle of Pea Ridge, which he describes in vivid detail.