series of impulses, but also by judicious choice of the same and order in which they are made to act upon the receiver.
Evidently there are a great many ways of 105generating impulses or disturbances at any wave length, wave form, number or order of succession, or of any special character, such as will be capable of fulfilling the requirements above stated, and there are also many 110ways in which such impulses or disturbances may be made to coöperate and to cause the receiver to be actuated, and inasmuch as the skill and practical knowledge in these novel fields can only be acquired by long experience 115the degree of safety and perfection attained will necessarily depend upon the ability and resource of the expert who applies my invention; but in order to enable the same to be successfully practiced by any person 130possessed only of the more general knowledge and experience in these branches I shall describe the simplest plan of carrying it out which is at present known to me.
For a better understanding of the subject 125reference is now made to the accompanying drawings, in which—
Figures 1 and 2 represent diagrammatically an apparatus and circuit connections employed at the sending and receiving stations 130respectively, for the practice of my invention; and Figs. 3, 4 and 5, modified means which may be employed in the practical application of the invention.
In Fig. 1, S1 S2 are two spirally-wound coils 135or conductors connected with their inner ends to preferably elevated terminals D1 and D2, respectively, and with their outer ends to an earth-plate E. These two coils, conductors, or systems D1 S1 E and D2 S3 E have different and 140suitably-chosen periods of vibration, and, as pointed out in other patents relating to any system of energy and intelligence transmission, their lengths should be such that the points of maximum pressure developed therein 145coincide with the elevated terminals D1 D2. By suitably-chosen periods of vibration such periods are meant as will secure the greatest safety against interference, both mutual and extraneous. The two systems may 150have electrical oscillations impressed upon them in any desired manner conveniently by energizing them through primaries P1 and P2, placed in proximity to them. Adjustable inductances L1 and L 2 are preferably included 155in the primary circuits chiefly for the purpose of regulating the rates of the primary oscillations. In the drawings these primaries P1 and P2 surround the coils S1 S2 and are joined in series through the inductances L1 160L2, conductor F, condensers C1 and C2, brush-holders B1 and B2, and a toothed disk D, which is connected to the conductor F and, if desired, also to the ground-plate E, as shown, two independent primary circuits being thus 165formed. The condensers C1 and C2 are of such capacity and the inductances L1 L2 are so adjusted that each primary is in close resonance with its secondary system, as I have explained in other patents granted to me. The brush-holders B1 and B2 are capable 170independently of angular and, if mevessary, also of lateral adjustment, so that any desired order of succession or any difference of time interval between the discharges occurring in the two primary circuits may be obtained.175 The condensers being energized from a suitable source S, preferably of high potential, and the disk D being rotated, its projections or teethe p p coming at periodically-recurring intervals in very close proximity to or, as the180 case may be, in contact with conducting rods or brushes n n cause the condensers to be discharged in rapid succession through their respective circuits. In this manner the two secondary systems D1 S1 E and D2 S2 E are set185 in vibration and oscillate freely each at its proper rate for a certain period of time at every discharge. The two vibrations are impressed upon the ground through the plate E and spread to a distance reaching the 190receiving-station, which has tow similar circuits or systems e s1 d1 and e s2 d2, arranged and connected in the same manner and tuned to the systems at the sending-station, so that each responds exclusively to one of the two195 vibrations produced by the transmitting apparatus. The same rules of adjustment are observed with respect to the receiving circuits, care being furthermore taken that the tuning is effected when all the apparatus is200 connected to the circuits and placed in position, as any change may more or less modify the vibration. Each of the receiving-coils s1 and s2 is shunted by a local circuit containing, respectively, sensitive devices a1 a2, batteries205 b1 b2, adjustable resistances r1 r2 and sensitive relays R1 R2, all joined in series, as shown. The precise connections and arrangements of the various receiving instruments are largely immaterial and may be210 varied in many ways. The sensitive devices a1 a2 may be any of the well-known devices of this kind—as, for example, two conducting-terminals separated by a minute air-gap or thin film of dielectric which is215 strained or weakened by a battery or other means to the point of breaking down and gives way to the slightest disturbing influences. Its return to the normal sensitive state may be secured by momentarily interrupting220 the batter-circuits after each operation or otherwise. The relays R1 R2 have armatures l1 l2, which are connected by a wire w and when attracted establish electrical contacts at c1 and c2, thus closing a circuit containing225 a battery b3 and adjustable resistance r3 and a relay R3. From the above description it will be readily seen that relay R3 will be operated only when both contacts c1 and c2 are closed.230
The apparatus at the sending-station may be controlled in any suitable manner—as, for instance, by momentarily closing the circuit of the source S, two different electrical vi-
