Strowger and the invention of the automatic telephone exchange, 1879-1912

In 1889, Strowger of Kansas City, USA, devised an automatic means of communication between two subscribers. The automatic telephone system was first introduced to the UK in 1897. This system provided for each subscriber´s line to terminate on a two-motion switch and a multiple of subscribers´ lines appeared in front of each switch mechanism. In 1899 a Strowger exhibit embodied the principle of trunking and grouping used in all subsequent installations. This paved the way towards systems of virtually unlimited capacity and was introduced simultaneously in France and Germany