Nikola Tesla Patents
384 Subs very slowly with the distance. It is an incidental advantage, which is often of no small practical importance, that with the observance of obvious rules and precautions, the relative position of the receiving and transmitting circuits or devices is of little or no consequence. It is useful to point out the fact, however, that in many instances when receiving devices have been operated at a distance, the results have been erroneously ascribed to other modes of transmission while, in reality, this one was involved. Still another method, which was devised and described by me at a later date, is based upon my discovery that the atmospheric air, which behaves as an excellent insulator to currents generated by ordinary apparatus, becomes a conductor under the influence of currents or impulses of enormously high electromotive for ce which I have found means of generating. By such means air strata, which are easily accessible, are rendered available for the production of many desired effects at distances however great, which has heretofore been impossible, and this method furthermore allows advantage to be taken of many of those improvements which are practicable in the ordinary systems of transmission involving the use of à metallic conductor. Obviously, whatever method be employed, it is desirable that the disturbances produced by the transmitting apparatus should be as powerful as possible, and by the use of certain forms of high-frequency apparatus which I have devised and which are now well known, important practical advantages are in this respect secured. Fur-5
