Hawkesbury Mills
In 1805 Thomas Mears and David Patee leased islands in the Ottawa where they built a sawmill and a grist-mill. They constructed a dam across the channel to Hawkesbury West and there purchased 400 ha of land. In 1810 half of these properties were mortgaged to William and George Hamilton who later obtained full ownership. The Hamiltons enlarged the sawmill and made it one of the most productive in the province, exporting large quantities of "deals" (softwood planks) to Britain. The mills were owned by the Hamiltons with the nearby "Hawkesbury Post Office" settlement in 1858 to form the incorporated village of Hawkesbury.
Plaque via Alan L. Brown's site Ontario Plaques. Full page here.