LENARD, P. (PHILIPP). - THE LENARD WINDOW.

Ueber Kathodestrahlen in Gase von atmosphärischen Druck und im äussersten Vacuum. (On cathode rays in gases under atmospheric pressure and in extreme vacua).

Leipzig, Johann Ambrosius Barth, 1894. Without wrappers. In "Annalen der Physik und Chemie. Hrsg. von G. Wiedemann.", Neue Folge Bd. 51, No. 2. (Entire issue offered). Pp. 225-416 a. 2 plates. Lenard's paper: pp. 225-267 a. 1 arge folded lithographed plate, showing the apparatus. Clean and fine.

First appearance of Lenard's importent paper on cathode rays for the work on which he was awarded the Nobel Prize in 1905.

"After many experiments with aluminium foil of various thickness he was able to publish, in 1894 the paper offered), his great discovery that the plate of quartz that had, until then, been used to close the discharge tube, could be replace by a thin plate of aluminium foil just thick enough to maintain the vacuum inside the tube, but yet thin enough to allow the cathode rays to pass out. It thus became possible to study the cathode rays, and also the fluorescence they caused, outside the discharge tube and Lenard concluded from the experiments that he then did that the cathode rays were propagated through the air for distances of the order of a decimetre and that they travel in a vacuum for several metres without being weakened. Although Lenard at first followed Hertz in believing that the cathode rays were propagated in the ether, he later abandoned this view as the result of the work of Jean Perrin in 1895, Sir J.J. Thomson in 1897 and W. Wien in 1897, which proved the corpuscular nature of the cathode rays."(Nobel Prize.org).

Shiers "Early Television" no 239.

Order-nr.: 43650