Nikola Tesla U.S. Patent 725,605 - System of Signaling Patent Wrapper Page 15

E 3 ductors, or, if desired, bridges it by an adjustable condenser c3, thus altering the vibration of the system es3d3 at suitable intervals. and causing two distinct vibrations to be enitted in rapid succession by the sender. In Fig.4 a similar result is produced in the system e sd by periodically shortcircuiting the primary p², by a rotating disc with insulating are conducting segments, or otherwise. Again, in Fig.5 three distinct vibrations are caused to be emitted by a system e s5d5, the result being produced by inserting periodically a suitable number of turns of an induction coil L'in series with the oscillating system by means of a rotating disk D5 with two projections p5p5, and three rods or brushes n5, placed at an angle of one hundred and twenty degrees relative to each other. Corresponding to each of these cases, the receiving station may be provided with two or three circuits, similarly the as in Fig.2, it being understood, of course, that different vibrations or disturbances emitted by the sender follow: in such rapid succession upon each other that they are practically simultaneous, as far as the operation of the relays, such as R1 and R2 is concerned. Evidently, however, it is not necessary to employ two or more receiving circuits, but single circuits may be used at the receiving stations arranged exactly as the transmitting circuits illustrated in Figs. 3, 4 and 5, in which case the corresponding disks, as D3, D4, D5, at the sending sta tion, will be driven in synchronism with those at the receiving But no matter what specific plan may be followed end.j XXXXXXX it will be seen that the fundamental idea in my inven9 629