The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 172
nife-edge form, 6, on which is pivotedthe armature. The armature passes rightto the other end of the coil, and when acurrent passes the end c is attracted tothe soft-iron pole-piece d, and the shutter eis released by the catch moving downward. In this manneithe air space at one end is dispensed… … 160.—Full size
Telephone
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