164 History of Luminescence 



ZEDLER S UNIVERSAL LEXICON 



The next great work is the truly remarkable sixty-four volume 

 Grosses vollstdndiges Universal Lexicon aller Wissenschaften und 

 Kiinste luelche bisher durch menschlichen Verstand und Witz 

 erfunden worden, published by Johann Heinrich Zedler (1706- 

 1760) between 1732 and 1750. Each volume contains something 

 like 1,000 pages. It differs from previous compilations in that it 

 is a cooperative work of many authors. The articles on " Licht " 

 (1738) makes no mention of luminescence but the subject is rather 

 exhaustively treated under " Phosphorus " (1741) which is defined 

 as a substance which shines in the dark without burning. 



Many kinds of phosphor! were listed, again divided into the 

 natural and the artificial. Among the natural phosphori Zedler 

 included (1) the worms and beetles found among grasses and 

 bushes in summer, (2) damp rotten wood, (3) luminous fish, (4) 

 luminous flesh, (5) the luminous dust (Staubivesen) of hair when 

 rubbed against the grain. All of these have neither heat nor fire. 

 The list of artificial phosphors is especially interesting because of the 

 terminology used. They are of two kinds, (1) those that must first 

 be exposed to the light of day such as (a) the Phosphorus Bono- 

 niensis, also called P. italicus or P. mineralis, sometimes Lapis lumi- 

 nosus or Ignis frigidus,^^ prepared from the Lapis Bononiensis and 

 (b) the Phosphorus Baldeweinus or P. Hermeticus; (2) those which 

 will light day or night but previously require some movement such 

 as shaking, striking or pumping away the air. Of this sort are (a) 

 the Phosphorus mercuralis, when mercury is shaken in a vacuum; 

 (b) P. aethericus, when an evacuated tube is rubbed and light 

 appears; (c) P. scintillans, when a warmed silk handkerchief is 

 stroked between the fingers; (d) P. Hombergii made from sal ammo- 

 niac; (e) P. liquidus, prepared from Phosphorus urinae dissolved, 

 together with camphor, in clove oil; (/) various other varieties of 

 the element phosphorus. 



There is no attempt by Zedler to explain the origins of the light, 

 and the bioluminescences are merely mentioned by name, but every 

 possible variety of inorganic luminescence is considered and five 

 columns are devoted to Phosphorus urinae. The reader is referred 

 to the monographs of both Cohausen (1717) and Dortous de Mairan 

 (1717), described as a learned nobleman of France, for additional 

 information. 



^8 Note our modern term, " cold light," rather than " cold fire." 



