Note 1 — Chapter III
Reading edition
The fluorescence of atmospheric air under the influence of certain wave-lengths of radiation was described as long ago as 1911 in a lecture before the Royal Institution of Great Britain by Professor R. W. Wood of Johns Hopkins University. The very short rays discovered by Schumann were demonstrated to produce fluorescence in air. The experiments and a photograph of the phenomenon may be found reprinted in the Report of the Smithsonian Institution for 1911, which is available in many public libraries. See page 165 et seg.