or two until the pelt is distinctly plumped. They are then washed with fresh water to remove the excess of lime, drained, and then enter the tainting stove. By this method the pelts are obtained in better condition and are less liable to damage by local excess of putrefaction. In unwoolling the skins are placed over a beam and the true wool is pulled out by hand. The wool is graded as it is pulled and different qualities kept separate: ewe wool, lamb wool, hog wool, etc. The hair is next removed from face and shanks by means of a blunt "rubbing knife," and the pelt then immersed in water. In the other method of depilation, by painting, advantage is taken of the loose texture of the sheepskin fibre and of the fact that the wool root is nearly halfway through the skin. The flesh side of the clean skin is painted with a creamy mixture of lime in a strong solution of sodium sulphide (14°-24° Beaumé). Care is taken to keep the depilatant off the wool. The skins are folded flesh to flesh and left for a few hours or until next day before unwoolling, according to the strength of the sulphide solution. The depilatory action is entirely chemical, being due to the solvent action of the sulphide on the hair root. The lime is sometimes omitted. After pulling, the skins are opened up and washed in fresh water. The various classes of wool are sold to the wool-stapler and so to the woollen industry. As this is a mechanical rather than chemical industry, its discussion is beyond the scope of this volume. However unwoolled, the pelt still needs further treatment by the fellmonger. It needs liming and unhairing. This is done in the ordinary way in pits of milk of lime, through which the goods pass from old to new limes in the course of about a week. This plumps the fibres, separates the fibrils and kills the grease. Paddles are used also to save handling. Shearlings are sometimes limed 9-14 days and unwoolled without sweating or painting. After liming the skins are unhaired and fleshed, and placed in clean strong limes until sold to the tanner. Sheepskin pelts are sometimes preserved by pickling. This consists in placing them first in a solution of sulphuric acid (about 3/4 per cent.) together with some common salt. The pelts swell up and imbibe the acid solution. They are then placed in saturated brine, which causes a very complete repression of the swelling, the pelts being apparently leathered. In this condition or partly dried out they may be kept for years. The forces at work in this phenomenon are somewhat complex (see Part V., Section I.). The skins may be depickled by paddling in a 10 per cent. salt solution to which weak alkalies such as borax, whitening, carbonate and bicarbonate of soda, etc., have been added.