In the late 50's Allis Chalmers experimented with fuel cells to produce electricity and to power tractors. Propane was used for fuel in their fuel cell tractor which came out in 1959. The gas was in several cylinders housed beneath the rear axle and behind the driver’s seat. The gas was fed through to the banks of fuel cells which filled most of the space normally occupied by an engine. The tractor weighed 5270 pounds, had 1008 individual fuel cells arranged in four main blocks. The current produced by the cells was used to power a 20 h.p. electric motor which drove the tractor. Each fuel cell was about one quarter of an inch thick, 12 inches square, and produced approximately one volt of output to total 15 Kilo Watts. The speed was controlled by a single lever rheostat which controlled the amount of current fed from the fuel cells to the electric motor. Another lever was used to reverse the polarity of the current so the motor ran backwards. In a demonstration, the tractor delivered 3000 lb of drawbar pull under test, and pulled a two-furrow plough in dry, hard soil. The tractor ran smooth and quiet, its waste gases were clean, it had no moving parts, and it was twice as efficient as other tractors during that time period. Using the technology from this tractor Allis Chalmers would develop fuel cell Golf Carts, Fork Lifts and a Submersible for the Navy. On display at the Smithsonian