LUMINESCENCE AND INCANDESCENCE 37 



Ozone oxidizes organic matter with an accompanying glow 

 (Fahrig, 1890; Otto, 1896). Tiie light from ozone acting 

 on pyrogallol solution is especially bright under cer- 

 tain conditions. 



Eadziszewski (1877, 1880) gives a long list of sub- 

 stances, chiefly essential oils, which luminesce if slowly 

 oxidized in alcoholic solutions of alkalis. Formaldehyde, 

 dioxymethylen, paraldehyde, metaldehyde, acrolein, dis- 

 acryl, aldehydeammonia, acrylammonia, hydrobenzamid, 

 lophin, hydroanisamid, anisidin, hydrocuminamid, hydro- 

 cinamid, besides waxes, and such biological substances as 

 glucose, lecithin, cholesterin, cholic, taurocholic, and 

 glycocholic acids, and cerebrin, all luminesce on oxidation. 

 Eadziszewski himself and many other authors have com- 

 pared the light of organisms to this type of luminescence. 

 Indeed the incorrect identification of granules found in 

 the cells of practically all luminous tissues as oil drop- 

 lets, is largely due to the influence of Eadziszewski 's work. 

 Dubois (1901 h) has added esculin, and Trautz (1904-5) 

 many aldehydes and phenol derivatives, including vanillin, 

 papaverin, tannic and gallic acids, besides glycerol and 

 mannite to the list of biological substances oxidizing with 

 light production. Guinchant (1905) has described oxy- 

 luminescence of uric acid and asparagine, Weitlaner 

 (1911) of substances in humus and McDermott (1913) 

 of substances in urine and the anaerobic alkaline hydro- 

 lysis products of glue and Witte's peptone. Pyrogallol 

 is especially prone to luminesce, as was first noticed by 

 Lenard and Wolf (1888) in developing a photographic 

 plate with pyrogallol developer. Later the luminescence 

 was studied in some detail by Trautz and Schloringin 

 (1904-5) v7ho developed the well-known luminescent mix- 



