WOOL, the covering of sheep. Each fleece consists of wool of several quali ties and degrees of fineness, which the dealers therein take care to separate.
The fineness and plenty of our wool is owing, in a great measure, to the short sweet grass in many of our pastures and downs; though the advantage of our sheep feeding on this grass all the year, without being obliged to be shut up un der cover during the winter, or to secure them from wolves at other times, con tributes not a little to it.
This substance, the material of such im portant manufactures, possesses some cu rious chemical properties, none of which however are much illustrated by the va rious operations performed on it in manu facture, almost all (that of dyeing except ed) being purely mechanical processes. Some of the simple chemical properties of wool have been examined by M Achard, and compared with the corresponding properties of the hair of different animals. The copious generation of oxalic acid by treatment of wool with nitric acid, has been particularly described and explained by M. Bertholet in his beautiful research es on animal matter ; and the great solvent power of the caustic fixed alkalies, has by happily applied to some use y M. Chaptal, as a saponaceous compound.
Wool, in the state in which it is taken from the sheep, is always mixed with a great deal of dirt and foulness of different, kinds, and in particular is strongly imbued with a natural strong smelling grease. These impurities are got rid of by wash ing, fulling, and combing, by which the wool is rendered remarkably white, soft, clean, light, and springy under the hand. When boiled in water for several hours in a common vessel, wool is not in any way altered in weight or texture, nor does the water acquire any sensible im pregnation.
The action of the nitric acid on wool is very curious. When cold, this acid only disengages a large quantity of azotic gas ; but when warmed, much nitrous gas is given out, and at least two new acids are formed, vie. the malic and the oxalic, the latter is in greater abundance than even from sugar and nitrous acid, or any other hydro-carbonous basis. A small scum of a peculiar oil always arises during the ac tion of nitrous acid on these animal sub stances.
The carbonated allzalies have little ac tion on wool, but the caustic fixed alkalies, when digested with it, speedily weaken its fibre, .reduce it to a soft gelatinous pulp, and finally make a perfect solution. The alkali at the same time loses its al kaline properties, as it does in common soap. This saponaceous solution of wool is made for experiment in a few minutes, by boiling bits of wool or flannel in a caus tic alkaline solution ; and it has been re commended by Chaptal to be employed instead of common soap in cleansing cot ton and other goods in manufactures, as by this means a number of refuse bits and clippings of wool and woollen cloth, which are now thrown away, may be put to some use. This soapy solution does not lather well when agitated with water, neverthe less it acts very powerfully in cleaning cloth. It has a strong and somewhat of fensive smell, which is left at first in the cloth, but goes off by short exposure to the air.
Wool, either in a raw or manufactured state, has always been the principal of the staple articles of this country. The price of wool was, in very early times, much higher, in proportion to the wages of la bour, the rent of land, and the price of butchers' meat, than at present. It was, before the time of Edward III. always exported raw, the art of working it into cloth and dyeing being so imperfectly known, that no persons above the degree of working people could go dressed in cloth of English manufacture.
The first steps taken to encourage the manufacture of woollen cloths was by Ed ward III., who procured some good work men from the Netherlands, by means of protection and encouragement. The va lue of wool was considered as so essentially solid, that taxes were vested in that com modity, 'reckoning by the number of sacks ; and in proportion to the price of the necessaries of life, and value of silver, wool was at least three times dearer then than it is now. The manufacturing of cloth being once introduced into the country, the policy of preventing the ex portation of the raw material was soon evident ; and the first act was that of Henry IV. c. 2, by which the exportation of sheep, lambs, or rams, is forbidden, under very heavy penalties.