. American telephone practice . wn in Fig. 299, but shown in Fig. 300. When de-pressed the spring b depresses first the spring d into engagementwith the spring e, and immediately thereafter spring f into engage- THE DIVIDED MULTIPLE SYSTEM. 387 ment with the spring g. Meanwhile the spring, c, also depressed bythe spring b, has its forward end caught under the retarding springa. When the spring c is thus caught by the spring a, it is held inits depressed condition as it has not sufficient strength in itself toovercome the retarding action of this spring. The spring b, how-ever, is the strongest
. American telephone practice . wn in Fig. 299, but shown in Fig. 300. When de-pressed the spring b depresses first the spring d into engagementwith the spring e, and immediately thereafter spring f into engage- THE DIVIDED MULTIPLE SYSTEM. 387 ment with the spring g. Meanwhile the spring, c, also depressed bythe spring b, has its forward end caught under the retarding springa. When the spring c is thus caught by the spring a, it is held inits depressed condition as it has not sufficient strength in itself toovercome the retarding action of this spring. The spring b, how-ever, is the strongest of the group in its upward tendency, and whenrelieved of pressure from the button, K, engages with the upwardlybent portion of the spring c, and serves to drag it back to its normalposition against the retarding influence of the spring a. When re-lieved from the influence of the spring a, the spring c assumes itsnormal position and breaks contact with the spring b. The cycle of contacts made and broken upon the pressure and a-. FIG. OF SUBSCRIBERS SIGNALING APPARATUS. subsequent release of the button, K, is as follows: First, the makingof contacts between the springs d and e; second, the making of con-tacts between springs f and g; then, as the button rises, first, themaking of the contacts between the springs b and c; second, thebreaking of the contacts between the springs / and g; third, thebreaking of the contacts between the springs d and e, and fourth,the breaking of the contacts between the springs b and c. These makes and breaks occur in a definite order, and with a pre-determined time interval between them, the purpose of which willbe understood when the circuit connections are considered. The primary windings, p, of the induction coil, /, are connectedin series with the battery between the springs f and g. The sec- 388 AMERICAN TELEPHONE PRACTICE. ondary windings, s, of the induction coil are connected in series be-tween the springs b and e. The binding po
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