From the rotary intersection of US Route 202/ME Route 4 with US Route 302 in Windham, Maine. take US Route 202/ME Route 4 south about 3.4 miles. turn right onto Newhall Road, about a half-mile further, Newhall rd becomes Gambo rd at it's intersection with river rd. Go straight onto gambo rd for about 0.3 miles,to park at the mountain division rail trail, turn right onto Soccer drive a gravel road. otherwise, on street parking might be available near the end of gambo road.
The Wheel Mill at the Oriental Powder Mills in Windham, Maine. The Mill was a gunpowder manufacturer with mills located on the presumpscot river in Gorham and Windham,Maine. The company was one of the four largest suppliers to the Union forces through the American Civil War. This mill was operated using a large horizontal watherwheel that turned a gear where two heavy stone wheels were located on opposite ends of an axle. In the early mills, the granite or other stone wheels weighed close to 3 tons and were 5 1/2 feet in diameter and about 18 inches wide. Starting in 1884, heavy cast-iron wheels replacedd stone wheels. Each wheel rotated on it's axis as the pair revolved in a shallow, large diameter, steel pan containing a 2-4 inch layer of gunpowder ingredients(charcoal,sulfer,and saltpeter). To prevent explosions, it was necessary to keep the wheels from touching the metal pan. Each wheel had a wooden or copper scraper to prevent the gunpowder from "caking" on the wheel. This grinding and mixing process lasted from 6-20 hours.