The difference between "Crookes tubes" and "Geissler tubes" is this: In a Geissler tube the exhaustion is very much less than in a Crookes tube, the light which we see in the Geissler tube being due to the luminescence of the residual gas. (Transactions, Volume 9. Hertfordshire Natural History Society and Field Club. The Club. Transactions of the Hertfordshire Natural History Society and Field Club. 1898. стр. 136..)
William Crookes, On Radiant Matter. Lecture delivered before the British Association for the Advancement of Science, at Sheffield, Friday, 22 August 1879. The Popular Science Monthly, Volume 16. D. Appleton. The Popular Science Monthly. 1880. стр. 287.
Dyer, B.; Thorpe, T. E.; Harker, J. A.; Simmonds, C.; Perkin, F. Mollwo (1920). „Obituary notices: Sir William Crookes, O.M., 1832–1919; Thomas Fairley, 1843–1919; Walter William Fisher, 1842–1920; Antoine Paul Nicolas Franchimont, 1844–1919; Harold Cecil Greenwood, 1887–1919; Charles Edward Groves, 1841–1920; John Holmes, 1871–1919; Sir Boverton Redwood, Bart., 1846–1919; John Charles Umney, 1868–1919”. J. Chem. Soc., Trans. 117: 444—472. doi:10.1039/CT9201700444.
DeKosky, Robert K. (1973). „Spectroscopy and the Elements in the Late Nineteenth Century: The Work of Sir William Crookes”. The British Journal for the History of Science. 6 (4): 400—423. JSTOR4025503. doi:10.1017/S0007087400012553.
Weeks, Mary Elvira (1932). „The discovery of the elements. XIII. Supplementary note on the discovery of thallium”. Journal of Chemical Education. 9 (12): 2078. Bibcode:1932JChEd...9.2078W. doi:10.1021/ed009p2078.
Weeks, Mary Elvira (1932). „The discovery of the elements. XIII. Supplementary note on the discovery of thallium”. Journal of Chemical Education. 9 (12): 2078. Bibcode:1932JChEd...9.2078W. doi:10.1021/ed009p2078.
DeKosky, Robert K. (1973). „Spectroscopy and the Elements in the Late Nineteenth Century: The Work of Sir William Crookes”. The British Journal for the History of Science. 6 (4): 400—423. JSTOR4025503. doi:10.1017/S0007087400012553.