284 PEARLS AND PEARL-CULTURE. 



the introduction of the basis of the pearl attended with 

 very little difficulty, and, I should think, very little 

 absolute pain to the animal ; for it is only necessary 

 that the valves of the shell should be forced open to a 

 moderate breadth, and so kept for a few seconds by 

 means of a stop, and that then the basis should be in- 

 troduced between the mantle and the shell by slightly 

 turning down the former part and pushing the pieces to 

 some little distance by means of a stick, when the stop 

 may be withdrawn and the animal will push the basis 

 into a convenient place by means of its foot ; and of the 

 thirty or forty bases which I thus introduced, only one 

 or two were pushed out again, and these I do not think 

 had been introduced sufficiently far." 



In order that the experimenters in this mode of pearl- 

 producing may not be disappointed with the result, we 

 add these observations of Mr Gray: " In cutting these 

 pearls from the shell, it is necessary that the shell 

 should be cut through, so that the mother-of-pearl 

 button may be kept in its place ; for if the back were 

 removed, as it would be if the shell were not cut through, 

 the basis would fall out, and then the pearl would be 

 very brittle. The only objection that can be adduced 

 against these pearls is, that their semi-orbicular and 

 unequally- coloured sides preclude them from being 

 strung or used any other way than set ; but this fault 

 will always be the case with all artificially-produced 

 pearls, as the mantle can only cover one side of them ; 

 and the only pearls that will answer the purpose of 

 stringing are those found imbedded in the cells in the 

 mantle of the animal." 



In the 'Encyclopaedia Britannica,' vol. vi. p. 477, we 

 find this notice of the way of producing pearls artifi- 

 cially : " The shell is opened with great care, to avoid 

 injuring the animal, and a small portion of the external 

 surface of the shell is scraped off. In its place is in- 

 serted a spherical piece of mother-of-pearl about the 

 size of a small grain of shot. This serves as a nucleus 



