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The Innovators 

Calling315 refers to many telephone system innovators. Use the Search box below to find references to the innovators cited below and others not listed here.

In the story of the development of automatic rotary dial telephone systems, the early inventors of electromechanical exchanges played a pivotal role in shaping its direction. 

Of course, Alexander Graham Bell is renowned for inventing the telephone in 1876. Yet, it was the collective efforts of visionaries like A .B. Strowger (1891), who introduced the first practical and commercial dial-operated switch.  And Alexander Keith, who improved Strowger’s design (1895), invented the first practical rotary dial (1898) and line concentrator switch (1905). These men and many others truly revolutionized local telephone interconnectivity leading to operator-free long-distance  calling. 

In the early years, Romaine CallenderLorimar brothers, Erickson brothersF. McBerty, E.B. Craft, J.J. Carty, F. Jewett, J. Reynolds, G.A. Betulander, Nils Palmgren and E. Molina, among others, contributed to exchange design and the mathematical underpinnings of calling statistics.    

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