- 4
- 5
- The James River, Va Water-Power Development. 1.
- A Vintage machine shop manufacturing history project.
- A vintage water wheel machine shop manufacturing history project.
- 6
- Pennsylvania Water Power Company History. 1.
- Development of the Great Falls Power Company.
- A vintage water wheel machine shop manufacturing history project.
- 7
- Estacada, Oregon Hydro Power.
- THE JAMES LEFFEL & COMPANY HISTORY PROJECT.
- N13
- N15
- Pennsylvania Water Power Company History. 2.