1950 – Fairbanks-Morse “Grass Finder” Rotary Power Lawn Mower – (American)

The gasoline-powered Fairbanks-Morse Grass Finder has no cord. Run it around the outside of your lawn once to give it the feel of things and from then on it runs itself, feeling for the high uncut grass with its left hand, as it were, and following along the edge of the previous cut until it …