Nikola Tesla U.S. Patent 723,188 - Method of Signaling Patent Wrapper Page 53

610 6 trated in Figs. 3, 4 and 5. In Fig. 3 a transmitting system e 3 d3 is partly shunted by a rotating wheel or disk D3, which may be similar to that illustrated in Fig. 1, and which cuts out periodically a portion of the coil or conductor $3, or, if desired, bridges it by an adjustable condenser C3, thus altering the vibration of the system e s3 d3 at suitable intervals and causing two distinct kinds or classes of impulses to be emitted in rapid succession by the sender. In Fig. 4 a similar result is produced in the system_e_s4_d4 by pericdically short-circuiting, through an induction coil 13 and a rotating disk D4 with insulating and conducting segments, a circuit p4 in inductive relatbn to said system. Again, in Fig. 5, three distinct vibrations are caused to be emitted by a system e s5 d5, this result being produced by inserting periodically a number of turns of an induction coil L4 in series with the oscillating system by means of a rotating disk 35 with two projections p5 p5, and three rods or brushes n5, plaeed at an angle of 120 degrees relatively to each other. The three transmitting pys þystems or circuits thus produced may be energized in the same manner as those of Fig. 1, or in any other convenCorresponding to each of these cases, the receiving station may be provided with two or three circuits, in an analogous manner to that illustrated in Fig. 2, it being understocd, of course, that the different vibrations or disturbances emitted by the sender follow in such rapid succession upon each other that they are practically simultanecus, so far as the operation of such relays as R¹ and R2 is concerned. Evidently, however, it is not necessary to employ two or more receiving circuits, but a single circuit may be used also at the receiving station constructed and arranged like ient way. -9