This branch of industry was already known to the Romans, and Pliny tells us that Sergius Orata, a knight, was the first who established an artificial basin for the cultivation of oysters, and realised large sums of money by this ingenious invention. At present Harwich, Colchester, Whitstable, and many other sea-ports along our coast are famed for their oyster-stews, as are, in France and Belgium, Marennes, Havre, Dieppe, Tréport, and Ostend, where real British natives are cleaned and fattened for continental consumption.
The renowned oyster-parks of Ostend, the oldest of which celebrated its hundredth anniversary in 1860, are extensive walled basins, communicating by sluices with the open sea, so that the water can be let in and out with every returning tide. As microscopic algæ and animalculæ are produced in much greater numbers in these tranquil reservoirs than in the boisterous sea, the oysters find here much more abundant food, and being detached one from the other, they can also open and close their shells with greater facility, so that nothing hinders their growth. Thus fostered and improved by constant attention, they are greatly superior in flavour to the rough children of nature that are sent without any further preparation to market and condemned to the knife soon after having been dragged forth from their submarine abode. The highly prized green oysters owe their colour to the number of ulvæ, enteromorphæ, and microscopic infusoriæ, that are abundantly generated in the parks, and communicate their verdant tinge to the animal that swallows them.
In spite of their high price, which unfortunately debars the poorer classes from their enjoyment, the consumption of oysters is immense; so that in a commercial point of view they are by far the most important of all the mollusc tribes. Of the quantities eaten in London alone, it is impossible to give even an approximate guess, as no reliable statistics can be arrived at. Exclusive of those bred in Essex and Kent, in the rivers Crouch, Blackwater, and Colne, and in the channel of the Swale and the Medway, vast numbers are brought from Jersey, Poole, and other places along the coast. The Channel Islands alone, which export about 100,000 bushels a year, send a great part of their oysters to the metropolitan market.
The luxurious tables of Paris likewise consume unnumbered millions, and when we consider that, thanks to the railroad, even the most distant inland towns of the Continent may now be supplied with Ostend oysters, we cannot wonder that their price has risen enormously with the constantly increasing demand.
This great augmentation of value has naturally directed attention to the creation of new oyster-banks, and to the better management of those already existing, and fortunately the manner in which the mollusc propagates renders its culture in appropriate localities a by no means difficult task.
The oyster spawns from June to September. Instead of immediately abandoning its eggs to their fate, as is the case with so many sea-animals, it keeps them for a time in the folds of its mantle, between the branchial lamellæ, and it is only after having thus acquired a more perfect development that the microscopic larvæ, furnished with a swimming apparatus and eyes, emerge from the shell, and are then driven about by the floods and currents, until they find some solid body to which they attach themselves for life. In this manner the oyster produces in one single summer a couple of millions of young, which, however, mostly perish during the first wandering stage of their existence. Thus we see what rich rewards may be gained by protecting and fixing the oyster-larvæ at an early date; and that this can be done in many places without any great outlay of capital is proved to us by successful examples both in ancient and modern times.
Between the Lucrine Lake, the ruins of Cumæ, where of yore the Sibyl uttered her ambiguous oracles, and the promontory of Misenum, lies a small salt-water lake, about a league in circumference, generally from three to six feet deep, and reposing on a volcanic, black, and muddy bottom. This is the old Acheron of Virgil, the present Fusaro. Over its whole extent are spread from space to space great heaps of stones, that have been originally stocked with oysters brought from Tarentum. Round each of these artificial mounds stakes are driven into the ground, tolerably near each other, and projecting from the water, so as to be pulled up easily. Other stakes stand in long rows several feet apart, and are united by ropes, from which bundles of brushwood hang down into the water. All these arrangements are intended to fix the oyster-dust, that annually escapes from the parental shells, and to afford it a vast number of points to which it may attach itself. After two or three years the microscopic larvæ have grown into edible oysters. Then, at the proper season, the stakes and brushwood bundles are taken out of the water, and after the ripe berries of the marine vineyard have been plucked, they are again immersed into the lake, until a new generation brings a new harvest. Thus the indolent Neapolitans have for ages given an example which has but recently been imitated by the men of the North. In 1858 a mason named Beef (a name which, if not misspelt, would seem to point out an English origin) inaugurated the modern era of oyster cultivation, at the island of Ré, near La Rochelle, by laying down a few bushels of growing oysters among a quantity of large stones on the fore shore. His success encouraged his neighbours to follow his example, so that now already upwards of 4,000 beds or claires extend along the coast.
Between March and May 1859 a quantity of oysters taken from different parts of the sea were distributed in ten longitudinal beds in the Bay of St. Brieux, on the coast of Brittany. The bottom was previously covered with old oyster-shells and boughs of trees arranged like fascines, which afford a capital holding-ground for the spat. In 1860 three of the fascines were taken up indiscriminately from one of the banks, and found to contain about 20,000 oysters each, of from one inch to two inches in diameter. The total expense for forming the above bank was 221 francs, and reckoning the number of oysters on each of the 300 fascines laid down on it at only 10,000, these sold at the low price of 20 francs a thousand would produce the sum of 60,000 francs, thus yielding a larger profit than any other known branch of industry.
Encouraged by these successful examples, an English company has obtained a grant by Act of Parliament of a piece of fore shore lying between the Whitstable and Faversham Oyster Companies' beds, and thus admirably situated for receiving a large quantity of floating spawn from these establishments. There can be no doubt that oyster cultivation will spread further and further, and that ultimately all the worthless bays and lagunes along our coasts will be converted into rich oyster-fields, yielding a good profit to their owners and enjoyment to millions of consumers.