Nikola Tesla U.S. Patent 725,605 - System of Signaling Patent Wrapper Page 78

692 the conjoint action of all of said circuits, as set forth. 8. The combination with a transmitter adapted to produce. series of electrical impulses or disturbances of distinctive character and in a given order of succession, of a receiving apparatus comprising tuned circuits responding to such impulses in a corresponding order, and dependent for operation upon the conjoint action of said elements, a s set forth. 9. In a receiving apparatus, the combination with a plurality of sensitive circuits, severally tuned to respond to waves or impulses of a different kind or class, a receiving circuit con rolled by the sensitive circuits and a device connected with the receiving circuits adapted to be operated when said circuit is completed by the conjoint action of two or more of the sensitive circuits, as set forth. 10. A system for the transmission of electrical energy, . having in combination means for producing and transmitting two or more impulses of different periodicities to form a signal in a predetermined order of succession, as set forth. 11. In a system for the transmission of electrical energy, the combination with a transmitting apparatus comprising one or more circuits, means for im pressing there in oscillations or impulses of different character an a receiving apparatus comprising a plurality of circuits each tuned to respond to the impulses of one kind produced by the transmitter and a receiver dependent for operation upon the conjoint action of the receiving circuits, as set forth. 12. In a system for the transmission of electrical energy, the combination with a transmitting apparatus comprising a transformer and means for impressing upon the secondary element of the same oscillations or impulses of different char