Turning Back the Clock: The 1951 Bell Manual for Operating a Rotary Telephone
In 1951, Bell Telephone System introduced a guide titled “The Telephone and How We Use It,” designed to aid elementary school students and others in understanding the operation of classic rotary dial phones. The guide detailed everything from basic phone use, handling emergencies, to polite phone manners.
h/t: rarehistoricalphotos
The journey towards the invention of rotary dial phones began in 1836 with various proposals for dials to send telegraph signals. The first commercial telephone exchange in 1878 prompted the need for an automated, user-controlled method to direct calls. Overcoming existing technical limitations, Almon Brown Strowger invented a telephone dial in 1891. Early rotary dials, unlike the ones we know today, used lugs on a finger plate and disrupted two independent circuits for exchange switch control.
Two main dial mechanisms emerged in the United States, one by Western Electric Company for the Bell System, characterized by spur gears, and the other by Automatic Electric Company, featuring a governor with worm gearing. Both utilized wrap-spring clutches for driving their governors, a common feature within turntables of the early 20th century.