Lt. Harper served in Company B (Van Dorn Guards), 38th. Miss. Infantry (Mtd) from March/1862 until his resignation in June/1862 due to health problems. There are ten cards in his military service file, one of which includes his hand-written resignation, these records may be procured at this site. http://history-sites.com/research/index.html

A capsule history of his unit is available at this site.
http://mississippiscv.org/MS_Units/38th_MS_Inf.htm