Montana inventor William Beeson offered the swimming apparatus above in 1881 — a suit fitted with a membrane that “acts like wings or fins, which, from the movement of the legs and arms effect a propulsion through the water.”

In 1910 O.B. Lyons patented the “life preserver and swimming machine” below — just turn the handle to drive the propeller.

Presumably you could combine the two to go twice as fast.