watch the motion of the waves, particularly when the element is violently agitated by tempests; nor should they indulge in sloth or inactivity, but take proper and frequent exercise, such as working at the pump, &c. for indolence only tends to aggravate the disorder.—Lastly, whatever may disturb or enervate the mind, such as reading, intense study, or meditation on gloomy subjects, must be purposely avoided, and no opportunity neglected, of participating in innocent mirth, and mental relaxation.
SEA-SLUDGE, or Salt-clod, is the surface, or that part of a saline marsh, which is deposited by the high tides. It is much richer, and less intermixed with sand, than the land which is more regularly overflowed.
Sea-sludge is an excellent manure; and though it be attainable only in a few situations, yet it deserves to be more generally employed. The best sludge is completely covered with grass: it is cut out of the marshes, to the depth of a spade, and, during the summer, is carted upon the land; on the surface of which it is spread, and suffered to remain in small clods, till it has become thoroughly mellowed by the winter frosts. It is then pulverized, by passing a harrow over the soil, after which it is ploughed-in with a thin furrow, for spring corn.
The proportion of this manure necessary for an acre, varies in different places, according to the nature of the ground; but, in general, it will be advisable to spread as much as will form a coat, or stratum, about an inch and a half or two inches in thickness. In some parts of Lancashire and Cheshire, sea-sludge is occasionally employed as a substitute for marle, to which it is greatly superior, both on account of its ameliorating properties, and the longer duration of its effects; instances having occurred, in which land, manured with such mire to the depth of two inches, has retained its fertility thirty years.
SEA-WATER, denotes the salt-water of the ocean.
The salts which this fluid contains, are, 1. Common marine, or culinary salt, compounded of fossil alkali, or Soda, and marine acid; 2. Salited magnesia, or a saline substance formed by the combination of marine acid with magnesian earth; 3. A small portion of selenite, or gypsum.—The quantity of saline matter obtained from the water of the British seas, is estimated by Neumann, to be about one ounce in each pint.—See also the article Salt, p. 14.
Sea-water is of great utility for various purposes. It affords an excellent manure, either sprinkled on land, by means of the machine described in the article Kitchen-Garden; or, when it is mixed with putrescible matters, formed into a compost, and distributed over the soil. In a medicinal view, Dr. Russel (Dissertation concerning the Use of Sea-water in Diseases of the Glands, &c. 8vo.) states the following cases, in which this fluid may be drunk with advantage, namely, in all glandular obstructions, as well as in swellings of the neck, and other parts; in all cutaneous diseases; in recent obstructions of the liver and kidnies (provided the stone in the latter be not large); in bronchocele, or tumors in the wind-pipe; and, last-
ly,
