The George E. Prothro mill was listed in the Reference Book of the Lumbermen's Credit Association, January 1905 as a sawmill and in the 1907 edition as a shingle mill.
Prothro was sawmilling as early as 1898 at his place north of Hallsville. Mortgage records for that year reveal he had a contract with the First National Bank on the sawmill, engine, and boiler. In 1906, Prothro's steam machinery included a 36-inch by 12-foot boiler and an 8-inch by 12-inch steam engine.