One-Legged Hopping Tank

This design, patented in 1945 by Henry Wallace, never made it into mass production (or, I suspect, even a prototype). Odd, that. From the text of the patent:

One of the objects of this invention is to provide a tank having an extensible leg capable of imparting a series of vertical oscillations to the tank, and having means to vary the angle of inclination of the leg to obtain directional movement of the tank.

Another of the objects of the invention is to provide a tank which is adapted to traverse difficult terrain.

Yet another object of the invention is to provide a tank which is propelled in such a manner that its progress is intermittent, thereby rendering it a difficult target. Still another object is to provide a tank provided with means whereby the direction of its course may be rapidly changed, thereby rendering it a difficult target.

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