Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 4, 1802).djvu/114

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S O A
S O A

solea, L. a fish that abounds on the British coasts, and is of various sizes; those taken on the western shores weighing from six to seven pounds each; while such as are caught on the eastern coast, seldom exceed one, or at the utmost, two pounds in weight. The upper part of its body is of a deep-brown colour, and the belly is perfectly white.

These fish are taken by means of trawl-nets, at every season of the year; but, by the 1 and 2 Geo. I. c. 18, they are prohibited to be caught, if less than seven inches in length, from the eye to the tip of the tail.

Soles are highly esteemed on account of their delicate flavour; the facility with which they are digested; and the rich nutriment they afford: these good qualities, however, are supposed to decrease in proportion to their larger size. Hence, the most diminutive are justly preferred; but they ought to be dressed as soon as possible, because their delicacy is impaired by keeping.

SOAP, a composition of fixed alkaline salt, in a state of combination with animal or vegetable oil: it is sometimes dry and hard, at others soft and liquid; being manufactured in various ways, with and without heat; but, as these depend on the same principle, we shall state only the common methods.

Where large quantities of soap are to be formed, heat becomes indispensable. For this purpose, a ley is made of soda and quick-lime, in the proportion of four parts of the former to one of the latter; and which is sufficiently strong to bear an egg. Equal parts of such ley, and of some tallow, or oil, are next poured into a copper, placed over a gentle fire, and stirred continually, till they begin to unite; when the rest of the ley is added, and the agitation continued, till the ingredients be completely incorporated. The mixture is next cast into proper vessels, at the bottom of which a little pulverized chalk is spread, to prevent it from adhering: and, in a few days, the soap acquires a sufficient degree of consistence, to be taken out, and formed into oblong squares.

Such is the process by which the various kinds of soap are manufactured; the only difference being in the oils employed in the composition. Thus, the common hard soap is prepared from the caustic ley above-mentioned, with the addition of tallow. The Venice, Alicant, or Spanish Soap, with olive-oil; Green Soap with that of rape, hemp, or linseed; Black Soap with train-oil; and, lastly, the ordinary Soft Soap is formed by using pot-ash as a substitute for soda, together with tallow, or train-oil; to which is added a large quantity of common salt.—The perfumed compounds, known under the names of Palm, Violet, Almond, or other Soaps, are prepared in a similar manner; the oils of such vegetable substances being employed, instead of those of the usual kind.

The vegetable oils, as well as the fat of animals, generally consumed in the manufacture of soap, raising this article to a high price, experiments have successfully been made, with a view to substitute fish-oil. The only objection to its general use, is a disagreeable smell, of which it cannot be easily divested.—With a similar design, Chaptal has proposed to employ

wool.