In 1864, a farmer digging for water at the site of the present city found coal instead. Deposits were substantial and the demand for coal in nearby Chicago was high, so companies rushed to acquire land and set up operations. A mining boomtown sprang up, a post office was established in 1867, and the community was called Keeversville. James Braidwood was an early member of the community, and in 1872 he was hired by one company to superintend the sinking of the first deep mine shaft. The addition of more deep-shaft mines followed, and on March 4, 1873 the city was incorporated