Untersuchungen ueber die Ausbreitung der elektrischen Kraft

Leipzig: Johann Ambrosius Barth, 1892. Untersuchungen über die Ausbreitung der elektrischen Kraft. Leipzig: Johann Ambrosius Barth, 1892.

First edition. Octavo (8 7/8 x 5 5/8 inches; 225 x 145 mm). pp. vi, [2], 295, [1] pp. Engraved illustrations and diagrams in the text. With original orange front and back wrappers bound in. Tipped in to the front is an ALS to "Colleague" signed Robert Watson-Watt and dated 12/10/68. The letter thanks the colleague for the opportunity to read their First Edition copy of Hertz's book and mentions that Hertz was a "Great inspiration to my efforts in relation to Radio and to 'Direction Finding'- later to be called Radar."

In original orange wrappers, bound within modern half morocco over marbled boards. Spine with black calf spine label, lettered in gilt. Top edges red, others uncut. Wrappers with some rubbing and wear. Previous owner's old ink signature on front wrapper and title-page. Overall, a very attractive copy in the original wrappers and a nice modern binding,

First edition, containing Hertz's experimental proof of electromagnetic waves. "His discovery of the properties of reflection, refraction, and polarization in electricity, with this wave theory of electrical motion, laid the foundation for radiotelegraphy and radiotelephony" (Sparrow).

"Hertz was first encouraged to investigate the Maxwellian hypothesis [that electrical waves can be projected through space] by Helmholtz, his senior professor in Berlin. In the course of this work he induced cathode rays to pass through metals. His colleague, Philipp Lenard, inserted a metal plate in a vacuum tube and found that it acted as a ‘window' through which the rays could escape. It is said to have been with such a tube given him by Lenard that Röntgen discovered X-rays" (Printing and the Mind of Man). J.J. Thompson described the results of Hertz's experiments as 'one of the most marvellous triumphs of experimental skill'.

"This book is a rare specimen, for it is a clear explanation by a scientist of how he came to make his discovery. It is problem oriented, as well as clear and frank" (Berkson, Fields of Force, p. 214).

The papers in this volume had been published in various journals between 1887 and 1890. They comprise virtually all of Hertz's experimental researches. In the second part of the introduction Hertz gives an analysis of Maxwell's theory.

"Robert Watson-Watt was a pioneer of radar technology. Although he did not invent the idea of radio detection, he was the first to prove it could work on a large scale... One of his projects was to investigate radio interference and how it might be used to advantage in wartime. The Air Ministry set up a committee to advance air defences in the UK in 1933. Nazi Germany claimed to possess a 'death ray', which used radio waves said to be capable of destroying targets in Britain. Watson-Watt was asked to develop a response to this threat- a ray that could destroy German aircraft before they attacked. He believed such a thing was not feasible. However, he believed he could develop a machine able to detect an aircraft in flight before it was visible. He called this RADAR (Radio Detection and Ranging) as it used radio waves." (National Library of Scotland)

The Dawn of Science and Technology 116. Ekeloff 1454. Printing and the Mind of Man 377. Sparrow 101. See Dibner 71 for Über sehr schnelle elektrische Schwingungen of 1887 (included here on pp. 32-58).

HBS 68716.

$2,000.