PEARLS AND MOTHER-OF-PEARL. 391 



lining of its shell. Layer after layer is added, until finally we 

 have the round, lustrous gem for brides' fingers and the throats 

 of queens. 



It is possible that in some cases a wound throws off bony par- 

 ticles which become the nucleus of the pearl ; or, in place of sand, 

 the foreign substance may be a minute parasite, or a morsel of 

 seaweed, or one of the tiny siliceous vegetables known as diatoms, 

 or even one of the eggs of the oyster itself. Some such encysted 

 particle, though perhaps of microscopic size, lies at the center, 

 and was the cause, of every pearl. So the pleasure-giving gem is 

 really the outgrowth of pain. 



Now, it has been discovered that, instead of waiting the acci- 

 dental intrusion of the alien particle into the shell of the oyster, 

 grains of sand, or other objects, for the nucleus of the pearl, may 

 be deliberately inserted by the hand of man, and that the oyster 

 will at once set to work at pearl-making. It is known that the 

 Chinese, from a remote period, have ingeniously taken advantage 

 of this singular self-defense of the oyster. In the month of May 

 the river mussels are taken from the water, and small pellets of 

 clay, and even tiny images of the gods, are slipped inside the 

 shells. The mussels are then replanted and left half a year. In 

 November they are taken up again, and, while some of the shell- 

 fish die, most have coated the clay pellets and little metal gods 

 with nacre, producing real pearls and genuine mother-of-pearl 

 deities. 



These mother-of-pearl Buddhas are in great demand with the 

 curious and the devout, but there is no evidence that any of the 

 priceless pearls of the world have been so produced. And yet 

 surely the results obtained suggest great possibilities for the en- 

 terprising man who shall establish the oyster ranches already 

 mentioned, and who shall add to the ingenuity of the Chinese all 

 the resources of modern science. 



The thin layers of nacre are always deposited thicker in de- 

 pressions than over elevations; hence uneven surfaces become 

 level, and small particles of whatever form gradually become 

 spherical. The perfect round pearl, however, can only result 

 when the nucleus penetrates the soft body of the oyster, or re- 

 mains unattached to the shell. Often it does become so attached, 

 and when removed has a defect on one side, and can only be used 

 in settings where that side is hidden ; such pearls are called hou- 

 fons or button pearls ; odd, irregular shapes are called baroques. 



Large or heavy intruding objects are quite likely to become 

 attached to the lower half of the shell. Such objects often, in the 

 course of years, are buried from sight under successive layers of 

 nacre. Some Chinese Buddhas thus imbedded in the flat or lower 

 halves of the bivalves are to be seen in London museums, and they 



