To picture the basic workings of the engine and the propellers, imagine riding a ten-speed bicycle up a very steep hill. Using the low gears allows the rider to pedal quickly but comfortably, while the wheels rotate slowly, pushing the bicycle up the hill. In the case of the Wright Flyer, the engine acted in the same way as the bicycle rider, expending energy by pedaling quickly. The propellors did the job of the bicycle wheels, turning the engine’s work into power (thrust) through the use of gears.