Telephones, their construction and fitting; a practical treatise on the fitting-up and maintenance of telephones and the auxiliary apparatus (1892)
Allsop, Frederick Charles · London, New York, E. & F.N. Spon · leaf 222
hange,or they may be wholly private lines. As shown in Fig. 183,the stations are represented as being all private ones and No. 2is speaking to No. 3, the switch being in the central position.When the handle of the switch is to the left-hand side. No. 2station is in connection with No. 1, while No.… … Fig. 183.Base
Telephone
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