Notes on electricity and magnetism. designed as a companion to Silvanus P. Thompson's Elementary lessons (1891)
Murdock, J. B. (Joseph Ballard), 1851-1931, Thomson, Silvanus Phillips, 1851-1916 · New York, Macmillan & Co. · leaf 146
~Fig- 35.—Relay. direction, the relay works for every signal from which eveiway it may come. In the open-circuit system a relay isnecessary for messages in each direction. The WesternUnion relay is shown in Fig. 35. The printing receiver or embosser is but little used inAmerica, messages being read… … Fig. 36.—Sounder.consists of two electromagnets which attract an armature 134 NOTES ON whenever the local current passes. The armature is at-tached to a lever, which makes a sharp click by strikingagainst a stop whenever the armature moves. After alittle practice the operator can read the message…
Electricity · Magnetism
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
