Electric Game Innovation 1930s

Only Luck Can Win In New Electric Game Innovation
Pure chance controls an amusement device known as the “thyratron speed trap,” Recently designed by electrical engineers.

The object of the game is to roll a steel ball representing an automobile, down a runway without lighting any one of three lamps.

Should a player succeed, he is said to have escaped the “speed trap.” Usually however, a light flashes upon one of three figures bearing legends “Constable Thyra fines 10 dollars”, “Sheriff Thyra fines twenty dollars”, and “Judge Thyra fines thirty dollars.”

As the ball rolls down, it successively closes electric circuits leading to as many thyratron or vacuum tubes, which act as relays to operate the lamps.
Because of an ingenious combination of direct and alternating current supply coupled in series to each tube, whether the tube operates at all depends upon the point at which the ball catches the alternating current cycle. This changes sixty times a second, and luck alone determines whether it will reinforce or cancel the direct current at the moment the ball makes contact.