Phosphorescence of Precious Stones 71 



Also coral has been credited with the same property. The work 

 Si king tsa ki ("Miscellaneous Records of the Western Capital," that is, 

 Si-ngan fu) relates: "In the pond Tsi-ts'ui there are coral-trees twelve 

 feet high. Each trunk produces three stems, which send forth 426 

 branches. These had been presented by Chao T'o, King of Nan Yue 

 (Annam), and were styled 'beacon-fire trees.' At night they emitted 

 a brilliant light as though they would go up in flames." 1 



Whether in each of the instances cited the case rests on real observa- 

 tion is difficult to decide. Some accounts may be purely fabulous or 

 imaginary, and the luminous property may have freely been transposed 

 from one substance to another. Taken all together, however, we cannot 

 deny that certain phenomena of phosphorescence might to a certain 

 degree have been known to the ancient Chinese in some way or other, 

 although the phenomenon itself was not intelligently understood. A 

 recent author, Sung Ying-sing, who wrote in 1628 (2d ed., 1637) the 

 T'ien kung k'ai wu, a treatise on technology, gives an interesting account 

 of the pearl-fishery, and discredits the belief in night-shining pearls. 

 He remarks, "The pearls styled 'moonlight and night-shining ' in times 

 of old are those which, when viewed under the eaves in broad daylight 

 on a sunny day, exhibit a fine thread of flashing light; it is uncertain, 

 however, that the night-shining pearls are finest, for it is not true that 

 there are pearls emitting light at the hour of the dusk or night." There 

 is, however, no account on record to show that the Chinese ever under- 

 stood how to render precious stones phosphorescent; and since this 

 experiment is difficult, there is hardly reason to believe that they should 

 ever have attempted it. Altogether we have to regard the traditions 

 about gems luminous at night, not as the result of scientific effort, but 

 as folk-lore connecting the Orient with the Occident, Chinese society 

 with the Hellenistic world. 



1 Tai p'ing yu Ian, Ch. 807, p. 5; or Vu shu tsi ch'ing, chapter on coral, ki ski, 

 p. 1 (see also Pien i tien 94, Annam, hui k'ao vi, p. 8 b, where this event is referred to 

 the beginning of the Han dynasty). 



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