A secondary source reports that Isaac Conroe had a sawmill at Egypt in 1875. Egypt today is located several miles south by west from Conroe. It was the general area of sawmilling from the 1870s to the 1890s, most notably led by the Oualline family. One of the steam logging tram roads was known as the Egypt & Montgomery.
Isaac Conroe was one of Montgomery County's most enduring sawmillers before 1900. His main offices and a sawmill were at Conroe but he operated mill locations at Egypt, about two miles to the southwest of the town; Haltom, location unknown; and his large sawmill at Beach, two miles east of Conroe, which he later sold to Trinity River Lumber Company.