Nikola Tesla Patents
530 varying the period of the oscillations impressed upon the Earth or, otherwise stated, by varying the length of the waves. In this manner the regions of maximun and minimum effect of the latter may be made to fall upon any receiving station or stations. It is, however, practicable to combine two or more oscillations of different wavelength and cause a resultà nt wave to travel over the globe at any speed desired, and thus produce a variety of useful effects. If the nodal and ventral regions are maintained in fixed positions the speed of a vessel carrying a receiving circuit may be exactly noted by observing the maxima and minima-rogions as they are successivaly traversed. Evidently also the course of the vessel may be easily determined without using a compass, as by a circuit connected to the Earth at two points, for the effect exerted upon the circuit will be greatest when the plates P Pare lying on a meridian passing through ground plate E, and will be nil when the plates are located at a parallel circle. In like ways the distance, of one point from another, the latitude and longitude, the hour, etc. may be determined from the observation of such stationary waves. Many other useful applications of my discovery will suggest themselves and in this respect I do not wish to limit rayself. As will be seen, my present invention does not reside in the apparatus either for transmitting or receiving electrical energy, which is herein described, but consists in an improvement in the art of transmitting elèctrical energy, which may be carried out either by the specific apparatus shown, or any other which is capable of -12