John B. McKinley, Sheriff of Smith County, bought a second mill in Smith County. It was located, in 1866, three miles east of Tyler at the Old Confederate Laboratory. Trinidad & Dempier of Louisiana owned the steam machinery. McKinley pledged as security for the loan land that he owned about seven miles south of Tyler.
Smith County registers record two more mortgages securing the sawmill property: the first in 1868 and the next a year later. McKinley used land about ten miles south of Tyler to secure the loans. It is uncertain if the sawmill had been moved from the Laboratory.
McKinley and Green B. Epperson earlier had owned another sawmill, about two miles west of the Laboratory (see entry).