Search Results for: Foot operated air pumps
secrecy, [ ] based on his mechanical engineering expertise and previous experience in design and manufacturing, it seems doolittle designed and crafted (and probably funded) the brass and the moving parts of the turtle, [ ] including the propulsion system, [ ] the navigation instruments, [ ] the brass foot-operated
water-ballast and forcing pumps, [ ] the depth gauge and compass, [ ] the brass crown hatch, [ ] the clockwork detonator for the mine, [ ] and the hand-operated propeller crank and foot-driven treadle with flywheel. [ ] according to a letter from dr. benjamin gale to benjamin franklin, doolittle also...
https://en.wikipedia.org/wiki/Turtle_(submersible)