PEARLS 599 



up all the pearls lie could find in the hands of the peasantry, thus stimulating the search 

 for more. It is estimated that the produce of the season's fishing in 1865 was worth at 

 least £12,000. This yield, however, was not maintained ; the rivers were over-fished, and 

 the industry was discouraged as it tended to interfere with the salmon fishing, and in some 

 cases to cause damage to the banks of the stream. At the present time a pearl is found now 

 and again by an occasional fisherman. 



The Scotch rivers which have yielded pearls are the Spey, the Tay, and the South Esk, 

 and to a lesser extent the Doon, the Dee, the Don, the Ythan, the Teith, and the Forth. 



In North Wales the Conway was at one time celebrated for its pearls ; and it is related 

 that a Conway pearl, which it is believed now occupies a place in the British crown, was 

 presented to the queen of Charles II. by her chamberlain. Sir Richard Wynn. In Ireland 

 the rivers of the counties of Donegal, Tyrone, and Wexford have yielded pearls. It is said 

 that, in England, Sir John Hawkins, the circumnavigator had a patent for pearl-fishing in 

 the Irt in Cumberland. 



The pearl-mussel is abundant also in Sweden and Norway from Schonen and 

 Christiansand as far north as Lapland ; and in the north of Russia, from the sources of the 

 Don and the Volga to the White Sea. The rivers of these regions yield a certain number 

 of pearls, among which are many of good quality. 



A pearl-mussel which differs in no essential particular from the European Unio 

 margaritifer is found in North America, and is specially abundant in the New England 

 States, but yields very few pearls. On the other hand, there are to be met with in the 

 river-system of the Mississippi a number of species of the genus Unio from which many 

 pearls are obtained. The first European discoverers of this region in the sixteenth century 

 found immense numbers of pearls, the largest being the size of a nut. The occurrence of 

 the fresh-water pearl-mussel in the Sandwich Islands has been noted already. 



The pearl industry of eastern Asia and particularly of Ch.ina is of peculiar interest. 

 Pearls are greatly esteemed by the Chinese as ornaments, and for that reason have been 

 eagerly sought for centuries. Pearl-producing mussels are said to inhabit some of the rivers 

 of Manchuria and East Siberia, but to what genera and species they belong is not exactly 

 known. The pearl-mussel which inhabits the water-courses near Canton and Hu-che-fu 

 further to the south is Cristaria plicala. This mollusc possesses a peculiar interest in that 

 for centuries it has been experimented upon by the Chinese in their attempts to induce it 

 to form pearls in response to an artificial stimulation. Thousands of Chinamen make this 

 a regular occupation, but their efforts are never (]uite successful. The manner in which 

 they proceed is to insert into the carefully opened mussel without injury to the animal a 

 small hemispherical object, or a thin image of Buddha in tin, which they place between the 

 mantle and the shell. These objects when invested with a layer of nacre acquire a pearly 

 appearance. After remaining inside the shell for a period ranging from 10 months to 

 three years, their nacreous coat is from yV to =- millimetre thick, and the objects can be 

 utilised for purposes of ornament. They are removed from the shell, to which they have 

 become firmly attached, and mounted in a suitable manner. 



Other sin)ilar attempts have been made to induce by artificial means the formation 

 of pearls, such as, for example, by the introduction of a grain of sand or of small 

 spheres of mother-of-pearl, but never very successfully. It is related that a method was 

 known to Linnaeus, which he had described in writing, but the details have never become 

 known. 



Not only have attempts been made to induce the formation of natural pearls by 

 artificial means, but no efforts have been spared to produce less costly substitutes which 



