According to the 1870 census records, Hart's water-powered saw and grist mill valued at a $3,000 capital investment manufactured 100,000 feet of lumber worth $1,500 and ground $3,300 of cornmeal. He paid three men $1,000 in twelve months. Raw materials included 3,000 bushels of corn valued at $3,000 and 500 logs valued at $200.