168 History of Luminescence 



Something like this is observed in shining wood; for some wood having 

 rotted in the ground, shall shine very briskly when taken out, the fire 

 having been kept in the contiguous earth: but in a day or two's con- 

 tinuance in the air it spends all its light and ceases to shine. T'is hard 

 to say how fire should thus be confined by ambient, loose, porous bodies; 

 or by what action such bodies should produce this effect. 



NEUMANN, WIEGLEB, AND OTHERS 



Considerable attention was paid to luminescence in later text- 

 books -^ on chemistry. Some of the best known were written by 

 Kasper Neumann (1683-1737) , Royal Pharmacist and professor of 

 chemistry in the Collegium Medico-Chiurgicum of Berlin, in 1740 

 and 1759; by Johann Friedrich Cartheuser (1704-1777) , the German 

 physician and professor of chemistry at Frankfort on the Oder, in 

 1736 to 1766; and by Jakob Reinhold Spielmann (1722-1783) , pro- 

 fessor of medicine, later of chemistry at Strassburg, in 1763 and 1766. 



In France, the earlier works of the chemist-physician, Pierre 

 Joseph Macquer (1718-1784), the Elemens de Chymie Theoretique 

 (1749) and Elemens de Chymie Practique (1756) , were quite popu- 

 lar but contain little on luminescence. Phosphors were considered 

 to be a weak sort of burning in his Dictionnaire de Chymie (1766; 

 2nded., 1778). 



The great German chemist, Andreas Sigismund Marggraf (1709- 

 1782) wrote no textbooks but his papers, brought together in 

 Chemische Schriften (1761 and 1767) , contain his analyses of and 

 views on phosphorescent substances, considered in Chapter VIII. 



A later chemistry which contained considerable on luminescence 

 was the Han dbuch der Allgemeinen Chemie (Berlin, 1781; 2nd ed., 

 1796) of Johann Christian Wiegleb (1732-1800), a pharmacist of 

 Langensalza, and also a senator. The first edition (1787) was trans- 

 lated into English as A System of Chemistry by C. R. Hopson, M. D., 

 in 1789. Although Wiegleb carried out no original researches on 

 luminescence, his book contains a very full account of every type, 

 both inorganic and organic, and includes such unusual things as 

 the observation that corrosive sublimate (HgCL) will light for 

 some days after sublimation whenever broken in the dark. He was 

 a strong believer in phlogiston, which is invoked to explain the 

 luminescences. 



^^ Practically nothing on luminescence is to be found in George Wilson, chymist— 

 A compleat course of chymistry, London, 1709; J. J. Becher— Grouse chymische Con- 

 cordance, Halle, 1726; A. 'Raume— Manual de chymie, Paris, 1765; L. B. Guyton de 

 Morveau— £/e/??e/zs de chymie, Dijon, 1776-1777; Wm. Nicholson— fzVsi principles of 

 chemistry, London, 1792. F. A. C. Gren's Systematische Handhuch der gesammte 

 Chemie (Halle, 1794; in English, 1800) contains a brief account of inorganic phosphors. 



