The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 48
hisgauge, which was inventedby the writer, are shown / (gp in Figs. 13 and 14. Bythe simple process of in-serting a copper wire inthe slots shown, and mov-ing the wire round until itis stopped, the instru-ment will furnish ninedifferent readings in re-gard to the electrical pro-perties, etc., of… … Fig. 12.—Full size
Telephone
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