Nikola Tesla U.S. Patent 725,605 - System of Signaling Patent Wrapper Page 42

656 Sub. Spec. M Brea oug spect NB such transmitting systems or circuits, and thus any desired degree of exclusiveness or privacy and safety against extraneous disturbances may be attained. The apparatus as illustrated in Figs. 1 and 2 permits, however, special results to be secured by the adjustment of the order of succession of the discharges of the primary circuits Pl and To ilP2, or of the time interval between such discharges. lustrate, the action of the relays R1 R2 may he regulated either by adjusting the weights of the levers 11 12, or the strength of the batteries b1 b2, or the resistances r1 r2, or in other well known ways, so that, when a certain order of succession or time interval between the discharges of the primary circuits Pl and P2 exists at the sending station, the levers 1¹ and 12 will close the contacts cl and c2 at. the same instant, and thus operate the relay R3, but it will fail to produce this result when the order of succession of or the time interval between the discharges in the primary circuits is another one. By these or similar means additional safety againstdisturbances from other sources may be attained, and, on the other hand, the possibility afforded of effecting the operation of signalling by varying the order of succession of the discharges of the two circuits. Instead of closing and opening the circuit of the source s, as before indicated, for the purpose of sending distinct siEnals, it may be convenient to merely alter the period of either of the transmitting circuits arbitrarily, as by varying the inductance of the primaries. Obviously there is no necessity for using transmitters with two or more distinct elements or circuits es S1 and $2, i