l methods of wireless
communication--both by telephone and by telegraph--are thoroughly
treated.

The drawings, diagrams, and photographs incorporated into the Cyclopedia
have been prepared especially for this work; and their instructive value
is as great as that of the text itself. They have been used to
illustrate and illuminate the text, and not as a medium around which to
build the text. Both drawings and diagrams have been simplified so far
as is compatible with their correctness, with the result that they tell
their own story and always in the same language.

The Cyclopedia is a compilation of many of the most valuable Instruction
Papers of the American School of Correspondence, and the method adopted
in its preparation is that which this School has developed and employed
so successfully for many years. This method is not an experiment, but
has stood the severest of all tests--that of practical use--which has
demonstrated it to be the best yet devised for the education of the
busy, practical man.

In conclusion, grateful acknowledgment is due to the staff of authors
and collaborators, without whose hearty co-operation this work would
have been impossible.

Table of Contents

VOLUME II

MANUAL SWITCHBOARDS _By K. B. Miller and S. G. McMeen_[A] Page[B] 11

Common-Battery Switchboards--Line Signals--Cord
Circuit--Lamps--Mechanical Signals--Relays--Jacks--Switchboard
Assembly--Transfer Switchboard--Transfer Lines--Handling
Transfers--Multiple Switchboard--Busy Test--Influence of
Traffic--Magneto-Multiple Switchboard--Multiple Boards: Series,
Branch-Terminal, Modern Magneto, Common-Battery--Western Electric No. 1
Relay Board--Western Electric No. 10 Board--Types of Multiple
Boards--Apparatus--Trunking--Western Electric and Kellogg Trunk Circuits

AUTOMATIC SYSTEMS _By K. B. Miller and S. G. McMeen_ Page 135

Automatic vs. Manual--Operation--Selecting Switch--Line Switch--Trunking
Systems--Two- and Three-Wire Systems--Subscriber's Station
Apparatus--First and Second Selector Operation--Connector--Release after
Conversation--Multi-Office System--Automatic Sub-Offices--Rotary
Connector--Party Lines--Two-Wire Automatic System--Lorimer
System--Central-Office Apparatus--Operation--Automanual
System--Operation--Subscriber's Apparatus--Operator's
Equipment--Switching Equipment--Distribution of Calls--Connection--Speed

POWER PLANTS AND BUILDINGS _By K. B. Miller and S. G. McMeen_ Page 227

Currents Emplo