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This artefact belongs to: © Bell Canada
A Bell representative demonstrates dial service to Toronto firemen, ON, 1924
Pringle and Booth Ltd.
1924, 20th century
Bell Canada Historical Collection
This artefact belongs to: © Bell Canada

Keys to History:

Automatic Switching and the Introduction of Rotary Dial Telephones

Automatic switching technology was introduced in the United States and in Europe in the 1900s. In Canada automatic switching was tested in Terrebonne and out West. After the First World War, the high demand for telephones forced companies to adopt this technology. In the 1920s, technological changes affecting local telephone service transformed the procedures to be followed. With the new automatic exchanges, subscribers used rotary dial phones that sought out the receiving number. From that point on, operators were no longer indispensable for local calls. Newspapers announced: "Subscribers won't need operators."

In the summer of 1924, Bell's first automatic switches were put into service at the Grover exchange in Toronto. The public had to be educated about this new technology because callers had to learn how to dial numbers. Now that we are used to Touch-Tone service, do we still know how to dial?


Automatic switching and rotary dial telephones were one of the major technological advances of the 20th century.


Bell Canada introduced automatic telephone service in Toronto in 1924 and in Montreal the next year.


In the 1920s, there was a strong surge in demand for telephone service. For example, in a big city like Montreal, between 1920 and 1930, an average of 11,000 phones were added to the system each year, as the population grew from 689,753 to 1,003,868. The annual growth rate of telephones in use (9.4 percent) was greater than that of the population (4.4 percent).


Automatic switching was invented by Almon B. Strowger (1839-1902), an undertaker in Topeka, Kansas. Legend has it that he came up with the system in order to bypass switchboard operators who were connecting potential customers to his competitors. The rotary dial telephone was invented in Chicago in 1896 by two engineers at the Automatic Electric Corporation.

© Musée McCord Museum