"Solar Activity and Cosmic Rays", in Nature.

HESS, Victor. "Solar Activity and Cosmic Rays", in Nature, London, published by Macmillan, 1933; this is the weekly issue of 14 October 1933, with the Hess paper on pp 601-602 (Letters to the Editor). The issue is cleanly and neatly extracted from a larger bound volume. VG copy. Provenance: Smithsonian Institution Astrophysical Laboratory, with their rubber stamp on front cover. [++] Hess (1883-1964) received the Nobel Prize in physics in 1936 "for his discovery of cosmic radiation." "When radiation and atoms interact, charged atoms, ions, are often produced. In 1912 Victor Hess measured atmospheric ionization as function of altitude using balloons. Surprisingly, he found that ionization first decreased, but then increased again at higher altitudes. He concluded that the upper atmosphere is ionized by radiation from space. He proved that this radiation is not solar through experiments performed at night and during eclipses: cosmic rays had been discovered."--Nobel Prize Foundation.