Pearl

Since the days of the Macedonians pearl-fishing has been carried on in the Persian gulf. It is said that the oyster-beds extend along the entire Arabian coast of the gulf, but the most important are on sandbanks off the islands of Bahrein. The chief centre of the trade is the port of Lingah. Most of the products of this fishery are known as "Bombay pearls," from the fact that many of the best are sold there. Very fine pearls are obtained from the Sulu archipelago, on the north-east of Borneo. The mother-of pearl shells from the Sulu seas are characterized by a yellow colour on the border and back, which unfits them for many ornamental purposes. Pearl oysters are also abundant in the seas around the Aru islands to the south-west of New Guinea. From Labuan a good many pearl-shells are occasionally sent to Singapore. They are also obtained from the neighbourhood of Timor, and from New Caledonia. The pearl oyster occurs throughout the Pacific, mostly in the clear water of the lagoons within the atolls, though fine shells are also found in deep water outside the coral reefs.

Pearl-fishing is actively prosecuted along the western coast of Central America, especially in the Gulf of California, and to a less extent around the Pearl islands in the Bay of Panama. The fishing-grounds are in water about 4of t. deep, and the season lasts for four months. An ordinary fishing-party expects to obtain about three tons of shells per day, and it is estimated that one shell in a thousand contains a pearl. The pearls are shipped in barrels from San Francisco and Panama. Some pearls of rare beauty have been obtained from the Bay of Mulege, near Los Coyetes, in the Gulf of California; and in 1882 a pearl of 75 carats, the largest on record from this district, was found near La Paz in California. The coast of Guayaquil also yields pearls. Columbus found that pearl-fishing was carried on in his time in the Gulf of Mexico, and pearls are still obtained from the Carib bean sea. In the West Indies the best pearls are obtained from St. Thomas and from the island of Margarita, off the coast of Venezuela. From Margarita Philip II. of Spain is said to have obtained in 1579 a pearl of 25o carats.

River Pearls.—River pearls are produced by the species of Unio and Anodonta, especially by Unio margaritiferus. These species belong to the family Unionidae, order Eulamellibranchia. They inhabit the mountain-streams of temperate climates in the northern hemisphere. The pearls of Britain are mentioned by Tacitus and by Pliny, and a breastplate studded with British pearls was dedicated by Julius Caesar to Venus Genetrix. As early as 1355 Scotch pearls are referred to in a statute of the gold smiths of Paris; and in the reign of Charles II. the Scotch pearl trade was sufficiently important to attract the attention of par liament.

The principal rivers in Scotland which have yielded pearls are the Spey, the Tay and the South Esk; and to a less extent the Doon, the Dee, the Don, the Ythan, the Teith, the Forth and many other streams. In North Wales the Conway was at one time

celebrated for its pearls ; and it is related that Sir Richard Wynn, chamberlain to the queen of Charles II., presented her with a Conway pearl which is believed to occupy a place in the British crown. In Ireland the rivers of Donegal, Tyrone and Wexford have yielded pearls.

River pearls are found in many parts of the United States, and have been systematically worked in the Little Miami river, War ren county, 0., and also on the Mississippi, especially about Muscatine, Iowa. The season extends from June to October. Japan produces fresh-water pearls, found especially in the Ano donta japonica.

Chinese Pearl Culture.

But it is in China that the culture of the pearl-mussel is carried to the greatest perfection. The Chinese also obtain marine pearls, and use a large quantity of mother-of-pearl for decorative purposes. More than a2 centuries before our era pearls are enumerated as a tribute or tax in China; and they are mentioned as products of the western part of the empire in the Rh'ya, a dictionary compiled earlier than l000 B.C. A process for promoting the artificial formation of pearls in the Chinese river-mussels was discovered by Ye-jin-yang, a native of Hoochow, in the 13th century ; and this process is still extensively carried on near the city of Teh-tsing, where it forms the staple industry of several villages. Large numbers of the mussels are collected in May and June, and the valves of each are gently opened with a spatula to allow of the introduction of various f or eign bodies, which are inserted by means of a forked bamboo stick. These "matrices" are generally pellets of prepared mud, but may be small bosses of bone, brass or wood. After a number of these objects have been placed in convenient positions on one valve, the unfortunate mollusc is turned over and the operation is re peated on the other valve. The mussels are then placed in shallow ponds connected with the canals, and are nourished by tubs of night-soil being thrown in from time to time. After several months, in some cases two or three years, the mussels are removed, and the pearls which have formed over the matrices are cut from the shells, while the molluscs themselves serve as food. Millions of such pearls are annually sold at Soo-chow. The most curious of these Chinese pearls are those which present the form of small seated images of Buddha. The figures are cast in very thin lead, or stamped in tin, and are inserted as previously de scribed. Specimens of these Buddha pearls in the British Museum are referred to the species Dipsas plicata. It should be mentioned that Linnaeus, probably ignorant of what had long been practised in China, demonstrated the possibility of producing artificial pearls in the fresh-water mussels of Sweden.