Canada’s First Automatic Telephone Exchange

Toronto factory testing section

Canada’s First Automatic Telephone Exchange

Jan 7, 2022 history by MikeHand

 

500 line Lorimer Exchange

We use the telephone today almost as an extension of our right hand without a thought to what goes into it. Or the history of its development. Want to call to the other side of the world? Not a pause or a thought about the intricacies of long distance calls. It was not always that way.

Lorimer phone with lever dial

Alexander Graham Bell made the first “long distance” telephone call in the late 1800’s all the way from Brantford to Paris, Ontario, about 10 miles, using lines strung along fence posts. Over the next twenty-five years, calls were directed manually by operators connecting lines.

Exchange section detail

In Brantford, the Lorimer Brothers worked on an electromechanical type of automatic exchange for many years before finally in 1899 getting something that worked. It was complicated, bulky – an exchange that could handle 500 lines occupied pretty well a whole room – but it worked and a number of cities in Canada, USA, France and England installed the system, including Brantford and Peterboro.

The Bell system eventually came up with an exchange design that worked on a different principle, although the principle of “preselection” conceived by the Lorimer brothers, where not all subscribers would be using the system at the same time, was utilised in pretty well all competing systems. The larger systems eventually were used more widely and the Lorimer patents and assets were eventually purchased by Western Electric, the manufacturing arm of A.T. & T. (the Ma Bell of the USA) and used as the basis for further developments by them.

Lorimer exchange on test in Toronto factory

Until the mid-1970’s, automatic exchanges were still operating via electromechanical systems, and one for a medium-sized manufacturing business would occupy pretty well a whole room. This changed rapidly when Mitel (another Canadian company) developed the solid-state exchange PBX system. The whole exchange now occupied only a small “box”, was faster and quiet and trouble-free.

See my book “The Lorimer Brothers.”