Nikola Tesla U.S. Patent 645,576 - System of Transmission of Electrical Energy Patent Wrapper Page 39

JOLI LILL }() } [ JUJUILLILIGIJ 650,343. in order to fully appreciate the invention. Sheet 3. According to the applicant's letter it appears that he regards 8000 meters or nearly five miles as a necessary and an even greater height as desirable for the practice of his invention. While it may be true that balloons have frequently reached such heights, it is manifest that these were not captive balloons. Again, the wire which would have to be led from them to the ground in order to establish connection with the ground introduce difficulties which were not present in the case of a simple free balloon. The Examiner regards that even with the present state of the art of aeronautics, the question of maintaining a terminal connected with the ground at an elevation of five miles is entirely problematical in its out come. At all events, the applicant. How does he must give the public some information on this point. propose to attain such an elevation? If the means of attaining the elevation are known, or if there be several known means, which of them does he propose to select? Summarizing this letter, the applicant should on the one hand give some proof of his statement that he has produced. currents which accessible atmospheric strata will convey by conduction. Or as he puts it in his specification, that it has become possible to transmit through even moderately rarefied strata. of the atmosphere electrical energy up to practically any amount [This page retyped from microfilm for better readability - Ed.] 157