Edited by refugerover, some rights reserved (CC BY-SA)
Photo Credits
- 1. (c) manual crank, some rights reserved (CC BY-NC-SA)
- 2. (c) Kathy, some rights reserved (CC BY-SA), uploaded by Kathy
- 3. (c) Frank Mayfield, some rights reserved (CC BY-SA)
- 4. (c) Peter Gorman, some rights reserved (CC BY-NC-SA)