Situflator: a tire-pumping rowing machine

The May, 1930 ish of Modern Mechanix featured this pneumatic tire-pump that appears to be a direct ancestor of the rowing machine: "The seat slides forward and backward on runners just as the seat on a racing boat does, enabling the operator to get a long, strong pull on the pump handle. As the work is distributed over the leg and back muscles, as well as those of the arms, the pump is pleasant and not fatiguing to use. The invention is appropriately called a Situflator."

New Easy-to-Operate Tire Pump (May, 1930)