146 PEARLS AND PEARLING 



pearls are thrown back into the water. The system is not 

 of value in places where shells are gathered in large quan- 

 tities for the button industry. The most modern method 

 of examining shells to see if they contain pearls is in the 

 use of the X-ray in the Tuticorin Fishery, Ceylon. By 

 the use of this strong light the pearls can be located in 

 the oysters and those which do not contain pearls are re- 

 turned to the water. The use of the X-ray for this purpose 

 has only been experimental. It is not likely that it will be 

 used to any extent in the United States unless pearl hunt- 

 ing can be developed, through scientific methods, to such a 

 high state of perfection that the proportion of shells con- 

 taining pearls, baroques and slugs, might be large enough 

 to warrant the use of the electrical machine. A very 

 common method used by most pearl hunters in opening 

 shells which have the appearance of containing pearls is 

 that of inserting a thin blade between the shells and cut- 

 ting the adductor muscles of the mollusk. 



Nearly all of the "crippled" shells are opened with a 

 knife and it is a very pleasant experience to open a "crip- 

 pled" mussel and find a valuable pearl inside of it. 



While a few are opened with knives, practically all of 

 the shells which are gathered in our northern rivers are 

 opened by "cooking out," or "boiling out," as it is called 

 in some places. The large quantities of shells which are 

 required for the manufacture of pearl buttons makes it 

 necessary to use a method by which the shells can be 

 opened without the loss of time. While the large quan- 

 tity of buttons are a necessity to the people, the killing 

 of such large numbers of mussels is a cause for regret. 



