In 1864, Dwight Keep constructed this typical canal era stone structure as the Benjamin C. Moore Company Mill. Around 1884, it was converted from a flour mill into one of the first water pumping plants in America, operated by the pioneering Holly Water Works as central pumping systems were being developed. In 1893, the building became Lockport City Hall and served that role until city offices moved to the new Municipal Building in 1974. The building is uniquely integrated with its canal environment: during the Barge Canal Improvement of 1905-1918, its north foundation wall was used as a retaining wall at the foot of Locks 34 and 35, and the Old Canal Raceway runs underneath it. Birdsill Holly, inventor of the Holly System of Direct Pressure Water Supply and Fire Protection for cities, towns, and villages, built the Holly Manufacturing Company complex on the banks of the Erie Canal, blasted an underground raceway to use surplus canal water to power his factory, mills, and other industries on both sides of the canal, and also achieved the invention of Central District Steam Heat.