258 



THE MICROSCOPE. 



pearly substance, that at first seemed to give countenance to such a 

 story. 



Mussels, in which these artificial pearls had been formed by the 

 Chinese, have been recently brought to this country by Mr. Raw son, from 

 one of which the preceding drawing was made (fig. Ill); it is repre- 

 sented of the natural size, with the simple pearls adhering to the shell. 

 The account furnished by this gentleman at the same time is, "that they 

 are only obtained near Ning-po. The Herm.es steamer being on a visit 

 to that place, he was able to obtain a few living specimens ; in which, 

 on being opened, several pearls, as many as eighteen or twenty, were 

 found in the course of formation. It appears they are formed by 



fig. 112. 



1. A transverse section of a Pearl from the Oyster, showing its prismatic structure. 

 2. A transverse section of another Pearl, showing its central cellular structure and 

 outside rings of true pearly matter. Magnified fifty diameters. 



introducing some pieces of wood or baked earth into the animal while 

 alive, which, irritating it, cause it to cover the extraneous substance 

 with a pearly deposit. Little figures made of metal are frequently 

 introduced ; and, when covered with the deposit, are valued by the 



