Nikola Tesla U.S. Patent 725,605 - System of Signaling Patent Wrapper Page 76

690 그 1. In a system for the transmission of electrical energy, the combination with means for producing two or more distinctive kinds of disturbances or impulses, of receiving circuits, each tuned to respond to the waves or impulses of cne kind only, and a receiving device dependent for operation upon the conjoint action of the several receiving circuits, as set forth. 2. In a system for the transmission of electrical impulses and the operation or control, of signalling or other apparatus thereby, the combination with a transmitter adapted to produce two or more distinctive kinds or classes of disturbances or impulses, of sensitive receiving circuits, each tuhed to respond to the impulses or disturbances of one kind or class only, and a receiving device dependent for operation upon the conjoint action of the sensitive circuits, as set forth. 3. In a system for the transmission of electrical inpulses, and the operation or control of signalling, or other apparatus thereby, the combination with a transmitter adapted to produce two or more distinctive kinds or classes of disturbances or impulses, of sensitive circuits at the receiving point or station, each tuned to respond to the impulses or disturbances of one kind or class only, a local circuit arranged to be completed by the conjoint action of the sensitive circuits and a receiving device connected therewith, as set forth. 4. In a system for the transmission of electrical impulses, and the operation or control of signalling or other apparatus thereby, the combination with a transnitting apparatus adapted to produce two or more distinctive kinds of dise