. American telephone practice . its right-hand position in contact with thehome button. After raising the pawl out of the notch on theratchet-wheel the dog slips out of the notch on the pawl, thus allow-ing the latter to return into contact with the ratchet-wheel, in orderto be ready for the next use of the telephone. In order, however,that the pawl may not engage the ratchet before the lever. A. has 42 AMERICAN TELEPHONE PRACTICE. fully returned to its normal position, a second dog, /, is provided,which is pressed by a spring so as to occupy a position under thepin, p, carried on the pawl, th
. American telephone practice . its right-hand position in contact with thehome button. After raising the pawl out of the notch on theratchet-wheel the dog slips out of the notch on the pawl, thus allow-ing the latter to return into contact with the ratchet-wheel, in orderto be ready for the next use of the telephone. In order, however,that the pawl may not engage the ratchet before the lever. A. has 42 AMERICAN TELEPHONE PRACTICE. fully returned to its normal position, a second dog, /, is provided,which is pressed by a spring so as to occupy a position under thepin, p, carried on the pawl, thus holding it out of engagement withthe ratchet-wheel until the rotation of the lever is nearly this pointa cam on the under side of the ratchet-wheel pushesthe dog, /, out of engagement with the pin, p, and thus allowTs thepawl to drop into position against the ratchet-wheel. It will beseen that this device accomplishes with certainty what the memoryof the telephone user could not be relied upon to do. This entire. FIG. 526.— HOLTZER-CABOT DESK SET. mechanism is well constructed, all of the parts subject to wear beingof hardened steel. The diagram of circuits given in Fig. 525 shows a system of wiringfor four stations equipped with this automatic return switch, thissystem being operated with the common calling battery and withlocal batteries at each station for talking purposes. Fig. 526 shows such a device applied to a desk telephone and alsoshows a method of wiring adopted in such systems. A cable hav-ing a sufficient number of conductors is run through each of the INTERCOMMUNICATING SYSTEMS. 743 stations to be served, and each conductor is brought out to a con-nector in a terminal box, as shown. To these terminals are alsosecured the conductors of the cable leading to the telephone instru-ment and switch. There is another way than by the use of the spring-actuated re-turn switch, of obviating the difficulty mentioned in regard to sub-scribers forgetting to sw
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