Nikola Tesla U.S. Patent 725,605 - System of Signaling Patent Wrapper Page 31

do sub Speeds do do a sensitive device and a relay included in each circuit, and adjusted to respond to the impulses or disturbances of one kind only, and a receiving apparatus in a local circuit controlled by the relays and adapted to be completed by the conjcint action of all of said relays, as set forth. 9. In a system of the kind described, the combination with a transmitter adapted to produce two or more series of electrical waves or impulses of different lengths, of a receiving apparatus compris ing a plurality of sensitive. circuits each tuned to respond to the impulses of one of the series produced by the transmitter, and a signalling device dependent for its operation upon the conjoint action of said circuits, as set forth. 10. The combination with a plurality of transmitter elements, each adapted to produce a series of impulses or disturbances of a distinctive character, and means for controlling and adjusting the same, of a receiver having a plurality of sensitive circuits each adapted to be affected by one of the series of impulses only, and dependent for operation up on the concint action of all of said circuits, as set forth. 11. 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 elements adapted to respond to such impulses in the same order, and dependent for operation upon the conjoint action of said elements, as set forth. 12. In a receiving apparatus, the combination of a plurality of sensitive circuits, each tuned to respond to -13645