Built in 1826 by James Thompson and Isaac Collier, Thompson Mill was expanded in 1850 when Thompson erected a larger four-story brick mill. All flour used by the Union Army during the Civil War was ground here. After a fire in 1872, Thompson's son John A. Thompson built a six-story brick mill. Flour was shipped to all parts of the U.S. The present dam was built by Thompson of Indiana limestone as the first stone dam in the Midwest. In World War I, Will Irwin of Columbus bought the mill and generated electricity for Union Starch and Refining Co. The mill was later given to the town, and for a time electricity was generated for town use. The mill was razed in 1957.