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changes a good many years ago.
The chief advantages of these
system over the Magneto are that it centralizes the battery 269 power required for operating the system, and so dispenses with
individual batteries at the subscribers' offices; it gives
the operators greater facilities for supervising the connections
and it reduces the work of the user of the telephone to a mini-
mua. To give the calling signal at the exchange it is only
necessary to lift the telephone from its support and the re-
placing of the telephone gives the clearing signal. The satis-
factory working of a C. B. exchange, however, depends very largely
upon the human element.
Wrong numbers are frequently
given, due probably in many cases to the calling subscriber not
speaking distinctly, and conversations are interrupted and some-
times broken off by irregular operation.
(13). To eliminate these difficulties the Automatic system has
been invented, in several forms, and is now being installed on a
very large scale in most of the countries of the world. In this
part of the globe it is already in use at Harbin, Darien,
Shanghai and Manila, and installations are being established at
Yokohama and Tokio. The system so far as local calls are con-
cerned is operated entirely by the subscribers. To give a call
a dial is turned successively to the digits of the wanted sub-
scribers number. Audible signals are given in the calling
subscriber's telephone indicating whether the called subscriber's
line is available or engaged. If disengaged the bell of the
called Subscriber rings practically simultaneously with the
dialling of the last digit. On finishing the conversation the
telephone is restored, and the Automatic apparatus engaged in
providing the connection is released. If desired, another
connection can be "dialled" at once.
(14). In operation the Automatic system has many advantages
Over the Manual. Connections are established easily and
quickly, the circuit is entirely under the control of the