76 



THE PEARL. 



of the animal, meets with a particle which has, by some 

 accident, been removed from the proper passages and 

 become stationary, we may suppose that it will adhere 

 to it, and form a layer about it ; which operation being- 

 successively repeated, produces in course of time those 

 white pellucid balls which we call pearls. 



Pearls are found throughout the whole substance of 

 the animal ; in the head, the coat that covers it, the 

 circular muscles that terminate it, the stomach, and, 

 in general, in all the fleshy and musculous parts of the 

 body. And, in confirmation of that account, which we 

 have briefly given of the mode of their formation, some 

 foreign particle is often found in the middle of the 

 pearl when cut through, which served as a nucleus or 

 centre for the commencement of that process. 



Unio was a name given by the Latin writers to the 

 pearl ; whence we sometimes meet with " union" as syno- 

 nymous with pearl. The origin of this word seems 

 to have been a persuasion that each pearl oyster pro- 

 duced only one pearl, which is contrary to observation, 

 as many of diff"erent sizes are often found in difi'erent 

 parts of the body of the same animal. The celebrated 

 Linneus stated, that he possessed the secret of rendering 

 a shell productive of pearls at pleasure. This was, 

 perhaps, by drilling a small hole in the shell, and then 



