The Abbé Dicquemare, fond of trying experiments in the spread of gastronomy, even to the stewing a mess of Gemmaceæ, the Gems of our water-vivaries, till they had something of the flavour of oysters, asserts that, when in a state of liberty, oysters can move from one place to another by suddenly admitting sea water into the shell, which they are able to open and shut with extraordinary power and rapidity, whereby they produce a strange sound; and this observation has been confirmed by other naturalists, and is recorded as an ascertained fact in several books of natural science. In like manner they defend themselves against smaller animals, especially against the spider crab, which constantly tries to penetrate into their half open shells. Much natural instinct or foresight is also attributed to the oyster; in proof of which I may name that, when in a position which is exposed to the variations of the tide, oysters seem to be aware that they remain for some hours without water, and consequently provide it within their shells.
This makes such oysters far more fit to be conveyed to a distance, than those taken nearer to the shore, which evacuate the water, thus exposing themselves to the heat of the sun, the cold, or an attack from their enemies; and this, too, is the reason why Colchester or Pyfleet oysters, packed at the beds, are in such request.
CHAPTER V.
THE OYSTER IN ITS NEW SETTLEMENT.
Dredging for Oysters; Oyster-beds and their formation; Sergius Orata; Pliny the Elder; Baia and the Lucrine Sea; Roman Epicurism and Gluttony; Martial and Horace, Cicero and Seneca; Masticate Oysters, and do not bolt them whole; Mediterranean and Atlantic Oysters; Agricola and the Rutupians; Apicius Cœlius, Trajan, Pliny, and the Vivarium.
The Oyster does not leave his home like the duckling, upon the call of "come here and be killed." If he is wanted, like Mrs. Glasse's hare, we must "first catch him." This is done by dredging, and this dredging for oysters is performed by means of rakes and scrapers, on which is fastened a bag of sail-cloth, leather, or net-work. These are lowered into the sea by means of ropes and chains, and are dragged along its bottom by boats in full sail, or by rowing-boats. When the net or scraper is drawn to the surface, the oysters are immediately separated from all else which may be swept up. These oysters are then stowed away and sent up to market in due course. But it is not of these that are formed the new settlements or oyster-beds, which I am about to describe.
These oyster-beds are cavities or reservoirs which communicate with the sea by means of canals, and are placed in such manner that the level beds remain dry when the tide is high. These beds are made with sand-stones or other hewn stones; and the water is kept in or let out at low tide by means of locks, or traps, as may he most readily effected.
At some periods, however, the water is kept in for many days, or even weeks together. In the latter case the oyster becomes, for the most part, very tender, and green and fat, because the stagnant water promotes the germination of those microscopical spores of marine plants, which always abound in natural sea-water, and upon which it delights to feed. These reservoirs, therefore, are not only the means of preserving them for sale, but of purifying them from the muddy odour which they have imbibed at sea, and which indicates them to be hard and devoid of that luscious and somewhat gastronomic quality so much prized by the world at large.
The bottom and sides of these caves or reservoirs are paved with stones and thick layers of sand, to keep them free from all mud, which is not only very injurious to the animal, but sure to harbour its enemies; and great care is also observed not to admit too great a flow of water at one time, as that might drive particles of sand into the shells. When the reservoir is properly prepared, the oysters are placed in their natural position—the flat side being upwards, in a sloping or horizontal direction. The more care that is taken in keeping their beds clean and free from mud, by washing the sides of the reservoirs, pouring water over the oysters, especially those which are dry, and removing the dead ones, which can be recognised by their shells being open, the better; for the more valuable will they be as human food, both as to profit and condition, and the more appreciated by the gastronomic million, who hail the oyster season as does a sportsman the advent of grouse and partridges, hares and pheasants.
The oysters, which are thus preserved, cleaned, nursed, and fattened are taken from their beds at the low tide when the water is out.
There are doubts, various and conflicting, as to whether oysters contained in reservoirs, where the water is changed each successive tide, are not on that account preferable to those which exist in the same water for two weeks at a time. I give a decided preference to the latter, though the water must be kept very clean by constant care and attention to the removal of the dead, the decomposition of which would otherwise, but for the frequent change of water, seriously affect the health of the whole settlement, by an accumulation of sulphuretted hydrogen, with a smell like that emitted by the Thames and other drainage rivers in the dog-days. These oysters slip down the human throat divine with a tenderness and sublime relish which no words can describe.