The Presumpscot River dropped 16 feet at Gambo Falls where the river formed the border between the towns of Windham and Gorham.
Sebago Lake formed a large natural reservoir upstream of Gambo giving the falls an unusually reliable water supply with comparatively minor flow peaking from storm runoff. Early European settlers built a
sawmill powered by the falls. In 1824 the sawmill was converted to a
powder mill by Edmund Fowler and Lester Laflin. Their Gorham Powder Company became known among the local population as the Gambo powder mills. Lester Laflin was a grandson of
American Revolutionary War gunpowder manufacturer Matthew Laflin. The Laflin family manufactured gunpowder in
Massachusetts for several generations. When Lester came east to Maine, his first cousins traveled west to build gunpowder mills in
New York and
Chicago. Lester, his partner, and their mill foreman drowned on Sebago Lake on 22 June 1827. Following an explosion killing seven employees on 19 July 1828, the Gambo Falls mill was enlarged by
Oliver Whipple concurrently with construction of locks for the
Cumberland and Oxford Canal. Whipple had been manufacturing gunpowder in
Lowell, Massachusetts since 1818. The new canal provided reliable transportation from
Portland harbor for
sulfur from
Sicily and
saltpeter from
India and from Sebago Lake for
charcoal and lumber from forests to the north. Whipple's Gambo mill used the lumber to manufacture
kegs holding as much as 25 pounds of powder. Kegs of gunpowder were shipped to Portland in canal boats when possible, but moved in
horse-drawn
sleighs when the canal was frozen. Canal boats carried about 25 tons, and sometimes sailed all the way to
Boston when weather was favorable. After plant explosions killed one employee each in 1835, 1847, 1849, 1850, and 1851, a major explosion on 12 October 1855 killed seven employees, including Whipple's brother and son, injured five more and destroyed a canal boat and parts of the mill. Manufacture of gunpowder in response to orders avoided the hazard of storing powder inventories until orders were received, but required water power on demand. The canal lock system controlled outflow from Sebago Lake; and, as a shipper interested in the well-being of its customer, canal management was receptive to regulating water releases to meet needs of the powder mill. ==Oriental Powder Company organized==