Nikola Tesla U.S. Patent 723,188 - Method of Signaling Patent Wrapper Page 21

B 578 a person possessed only of the more general knowledge and experience in these branches, I she. 11 describe the simplest plan of carrying it out, which is at present known to me. For a better understanding of the subject reference is now made to the accompanying drawings in which Figures 1 and 2 represent diagrammatically the apparatus and circuit connections employed at the sending and receiving stations respectively, and Figs. 3, 4 and 5 modified means which may be employed in the practical application of the invention. In Fig. 1 st and s2 are two spirally wound coils or conductors, connected with their inner ends to elevated terminals Dl and D2 respectively, and with their outer ends to an earth plate E. These two coils, conductors or systems Dl s1 B and 12 s2 E have different and suitably chosen periods of vibrations and, as pointed out in other patents relating to my system of energy and intelligence transmission, their lengths should be such that the points of maximum pressure developed there in coincide with the elevated terminals D1 D2. The two systems may have electrical oscillations impressed upon them in any desired manner, conveniently by energizing then through primaries pl and P2, placed in pro imity to them. Adjustable inductances 11 and 12 are preferably included in the primary circuits chiefly for the purpose of regulating the rate of the primary oscillations. In the drawing these primaries Pl and P2 surround the coils. s¹ s2, and are joined in series through inductances 11 12, conductor F, condensers Cl and c2, brush holders 31 and 32 and a toothed disk D, which is connected to the conductor F and, if desired, also to the ground plate E, as show, two -4