THE “A B C of the Telephone” is a book valuable to all persons interested in this ever-increasing industry. No expense has been spared by the publishers, or pains by the author, in making this the most comprehensive handbook ever brought out relating to the telephone.

——TABLE OF CONTENTS——

29 CHAPTERS

The Telephone Apparatus and its Operation; A Brief Survey of the Theory of Sound, Necessary to an Understanding of the Telephone; A Brief Survey of the Principles of Electricity; Electrical Quantities; History of the Speaking Telephone; Later Modifications of the Magnet Telephone; The Carbon Microphone Transmitter; The Circuits of a Telephone Apparatus; The Switch Hook and its Function in Telephone Apparatus; The Switchboard and the Appliances of the Central Station; The Operator’s Switch Keys and Telephone Set; Improved Switchboard Attachments; Switchboard Lamp Signals and Circuits; The Multiple Switchboard; Locally Interconnected or Multiple Transfer Switchboard; Exchange Battery Systems; Party Lines and Selective Signals; Private Telephone Lines and Intercommunicating Systems; Common Return Circuits; Private Telephone Lines and Intercommunicating Systems; Full Metallic Circuits; Large Private Systems and Automatic Exchanges; Devices for Protecting Telephone Apparatus from Electrical Disturbances; The General Conditions of Telephone Line Construction; Telephone Pole Lines; Wire Transportations on a Pole Line. Telephone Cables and their Use in Underground and Pole Lines; Circuit Balancing Devices; The Microtelephone; Wireless Telephony; Useful Definitions and Hints on Telephone Management.

With Ready Reference Index

The volume contains 375 pages, 268 illustrations and diagrams; it is handsomely bound in black vellum cloth, and is a generously good book without reference to cost.

PRICE, $1, Postpaid.

THEO. AUDEL & CO., 63 FIFTH AVENUE, NEW YORK