[Transcriber's Note: References to page numbers in table of contents
and index removed, as well as the numbers themselves.]

[Illustration: ALEXANDER GRAHAM BELL The Inventor of the Telephone.]


Cyclopedia

of

Telephony and Telegraphy

_A General Reference Work on_

TELEPHONY, SUBSTATIONS, PARTY-LINE SYSTEMS, PROTECTION, MANUAL
SWITCHBOARDS, AUTOMATIC SYSTEMS, POWER PLANTS, SPECIAL
SERVICE FEATURES, CONSTRUCTION, ENGINEERING,
OPERATION, MAINTENANCE, TELEGRAPHY, WIRELESS
TELEGRAPHY AND TELEPHONY, ETC.

_Prepared by a Corps of_

TELEPHONE AND TELEGRAPH EXPERTS, AND ELECTRICAL ENGINEERS OF
THE HIGHEST PROFESSIONAL STANDING

_Illustrated with over Two Thousand Engravings_

FOUR VOLUMES

CHICAGO