The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 192
elamps are in position, thesprings bear on the brassplates of the lamps, andthe holes in the frontebonite strip throughwhich the lamps are in-serted are closed by lamp caps, which are small brass sockets,in the front of which opal plano-convex lenses are fitted, as d,Fig. 192. These caps protect… … Fig. 192.—Scale \ i68 PRACTICAL TELEPHONE HANDBOOK to what privileges the subscribers to which they belong areentitled. See Chapter XVII. The lamp-jacks are made up in strips to correspond in sizeand number of jacks to the spring-jack strips, as shown inFig. 193, which represents a strip of twenty…
Telephone
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