At Saccarappa Falls on the Presumpscot River in Westbrook, the Knowlton Machine Shop on the right is where water wheels, stereopticon lanterns, generators, loom equipment and saws, among other things, were built.

In the center is the S.D. Warren Saccarappa Power Station and at the left is the Dana Warp Mill. The original building on the island was built and operated by George Warren as a woolen mill and he ran for only a couple of years before selling it in 1879 to Woodbury K. Dana, the owner of the Dana Warp mill.