If done by hand, the skins are placed on a sloping glass or slate table, with the flesh side uppermost, which is then stretched out by strong pressure with a tool known as a sleeker, the strokes being made downward in the direction of the hair growth. The flesh side done, the whole skin is turned over and the grain side is similarly treated. Sometimes only the flesh side is struck out, especially if the grain is soft and tender. The sleeker consists of an iron, steel, or copper blade, about 6 in. square, fitted in a wood handle (Fig. 32). The skins are hung up in the drying-room immediately they are extended and smoothed by sleeking, and are then either allowed to dry completely, or, as is generally the case with best leather, they are hung up until a great deal of the moisture is evaporated and the skins are left in a slightly moist, or, as it is generally termed, "sammed" condition. The skins are then taken down, damped in dry parts, folded over, laid in piles to equalise the moisture, and finally smoothed out and stretched again by hand or machine. This second operation after the dyeing is known as "setting." Chrome-tanned skins are usually stretched and nailed on square boards after setting, as, owing to their elasticity, they are liable to shrink considerably in drying. The superficial area can be increased by fully extending the skins. This operation is technically described as "straining." It may be stated here that vegetable-tanned leathers are not generally "strained" on boards, as such leather is better in quality and substance when hung up and dried. Leather of combined tannage (_i.e._, tanned with vegetable and chrome products) is, however, frequently "strained," as the astringent property of chrome would otherwise cause contraction of the fibres. When dried on the boards the leather is somewhat stiff, and has, therefore, to be softened before any finishing ingredients are applied. Chrome leather is softened by placing it for a few days in damp sawdust, which, for brown or fancy coloured leather, must be of deal or white pine, and, therefore, free from objectionable colouring matter; but, for black leather, the sawdust of any wood is suitable. The skins must be systematically piled one above the other, and a little damped sawdust scattered over each skin.