18 History of Luminescence 



pearances, which might be attributed to St. Elmo's fire or other 

 types of electric discharge, to clumps of luminous fungi, or to phos- 

 phorescent wood containing the mycelium of the fungus. These 

 phenomena are the equivalent of the ignes fatui of European folk- 

 lore, whose explanation is likewise difficult. In some cases lumines- 

 cences may also have been involved (see Chap. VII on Electro- 

 luminescence) . The accounts of ignes fatui in China and Japan, 

 together with a detailed discussion of them will be found in Need- 

 ham's History of Science in China, in de Groot (1901) -^ and in de 

 Visser (1913, 1914) .^^ It seems quite certain that in ancient China 

 philosophers were aware of most types of luminescence with the 

 possible exception of the light from artificial phosphors. 



It has been claimed that the Chinese knew of artificial phosphors, 

 although the evidence is not very convincing. The following story 

 concerning a painting of the Emperor Tsi Tsung (976-998) , of the 

 Sung dynasty, was related by a Mr. Macgowen ^^ in a communi- 

 cation to the North China Herald and has been included by H. 

 Rupp ^° in her book Die Leuchtmassen und ihre Verwendung 

 (Berlin, 1937). 



The story has been traced by Professor Lien-Sheng Yang, of Har- 

 vard University, to old Chinese records. I quote from a letter of 

 Professor Yang to Mr. Langdon Warner,^^ of the Fogg Museum of 

 Art of Harvard University: 



First, in the miscellaneous notes by a Sung monk, of which the title 

 is Hsiang-shan yeh-lu (eleventh century a. d.) , there is a story concerning 

 an interesting painting which was presented to the second emperor of 

 the Sung dynasty. On the painting was a cow which appeared during 

 the day as eating grass outside a pen but at night as resting in it. When 

 it was shown to the court, none of the officials could offer an interpreta- 

 tion. The monk Tsan-ning, however, said that the ink [or color] which 

 was shown only in the night was mixed with drops from a [special kind 

 of] pearl shell and the ink [or color] which was shown only during the 

 day was made by grinding a rock which had fallen from a volcano to 

 the seashore. He claimed that the information came from a book by 

 Chang Ch'ien, the famous envoy sent to the Western Regions by Han 

 Wu-ti [reigned 140-88 b. c.]. A scholar who consulted the imperial col- 



" J. J. M. de Groot, Religious system of China 4: 80-81, 1901. 



** M. W. de Visser, The dragon in China and Japan, Verhand. Kon. Akad. v. Wetens. 

 Amsterdam. Letterkunde N. R. 13, 242 pp., 1913; Fire and ignes fatui in China and 

 Japan, Mitteil. d. Seminars fiir Orient. Sprach. Kon. Univ. Berlin 17: 162-295, 1914. 



" MacGowen, Science 2: 698, 1883. 



^" Rupp (1937: 147) attributed the painting to the Japanese. 



^^ I express my appreciation to Mr. Warner and Mr. Yang for their efforts in tracing 

 this story. 



