Nikola Tesla Books
TECHNICAL APPENDIX the only electromagnetic wave transmission known was that of Heinrich Hertz who in 1888 used the free-space waves. Tesla's proposal was the first ground-guided system (today we call it the surface wave), which soon became the only one used in the early development of radio wave transmission technology. Hertz transmitter from 1888 emitting free-space wave In explaining the operation of his radio system, Tesla again came with a original theory, explaining that his system does not produce significant free-space radiation but rather it makes use of conduction by disturbing the electrostatic charge along the earth's surface. In the early days of radio some writers, misled by Tesla's theoretical explanation, made a distinction between the Tesla and Marconi systems! Today we know that this was wrong view. In his first patent (1896) Marconi used Hertz apparatus and Tesla's concept of antenna-ground combination to produce guided wave. Marconi was the first to send a message across the ocean, and thus, he is partly responsible for âdeveloping' radio, but he did not invent it. The apparatus and system of four tuned circuits he used was not his invention. The great radio controversy was a landmark decision of The United States Supreme Court in the case 'Marconi Wireless Telegraphy Company of America vs. United States' rendering invalid Marconi's basic patent from 1904 in view of the priority of Tesla's patents, issued 1900, as well as some elements of the approaches of Stone and Lodge. This decision was handed down after the death of both Marconi and Tesla yet seems not to have affected views of many historians who neglect the importance of Tesla's role in the early development of radio. 156
