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577
Automatic Telephone-Exchange System.
Patent for "a simple system and arrangement which is especially adapted for a telephone exchange, which enables the instruments to be connected by a single wire, which dispenses with the use of an operator at the central station, which has automatic means for registering the messages sent by each subscriber, and which is provided with an automatic switching device by means of which one subscriber may connect with any other" (lines 10-19).
Date:
December 5, 1893
Creator:
Serdinko, John
Object Type:
Patent
System:
The Portal to Texas History