Harry Williams (while working for Pacific Amusement Company) invented the tilt mechanism in 1932. The idea behind the mechanism was to stop people from lifting and moving the machine, so they could "win" at it. Another milestone for pinball history; since without it, the newer machines would never have gained their popularity as a game of skill. The tilt mechanism solved the problem of cheating. Tilt mechanisms include: the Plumb Bob Tilt, the Roll Tilt (both seen below) and weighted tilts such as slam, playfield and backbox tilts.
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