In 1951, Bell Telephone System introduced a guide for understanding rotary dial phones. It covered phone use, emergencies, and manners. The journey towards rotary dial phones began in 1836, and Almon Brown Strowger invented a telephone dial in 1891. Early rotary dials used lugs on a finger plate and disrupted circuits. Two main dial mechanisms emerged in the US, one by Western Electric with spur gears, and another by Automatic Electric with a governor and worm gearing. Both used wrap-spring clutches.

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