pieces of tat, &c. These preliminary operations are performed in 

 the following manner: — 



When the hides, which are to be tanned, are raw (in which state 

 they are called green hides), they are put to steep in water, in order 

 to clear them of the blood and hlth they may have collected in the 

 slaughter-house. They are left to soak in the water for some time, 

 and if the hides are dry, they are steeped a longer time, sometimes 

 for fourteen days; less in hot weather, or more in cold. They are 

 drawn out once or twice to see if they are well softened. The 

 neighbourhood and the command of water are necessary to these 

 operations. Without that the hides cannot be prepared. 



After the hides hav^e been well softened they next proceed to 

 cleanse or free them from the hair. With this intention several 

 different methods are employed; that which is the oldest, and still 

 most generally followed, consists in the application of lime. In all 

 tanneries, pits are formed underground, having their sides lined 

 with stone or brick, in which lime-stone is slacked so as to form 

 milk of lime. These pits are divided into three kinds, according 

 to the greater or less strength of the lime. The hides intended to 

 be scoured are first put into the weakest of these pits, wherein they 

 are allowed to remain until the hair readily yields to the touch. 

 If this liquor be not sufficiently active, they are removed to the 

 next in graduation. The time they are soaked is longer or shorter 

 in proportion to the strength of the lime, the temperature of the 

 air, and the nature of the hides. It has been proposed to substitute 

 lime-water in place of the milk of lime. But, though the lime- 

 water acts at first with sufficient strength, its action is not suffi- 

 ciently permanent, and, in order to succeed in clearing the hides 

 by this means, it is necessary to renew it occasionally; and in this 

 wav the hides may be prepared in a few days. In some tanneries, 

 after they have been kept in the pits for a short time, they pile 

 them up in a heap on the ground, in which state they are suffered 

 to remain during eight days; after which they return them into 

 the same pits from whence they were taken, and this process is 

 repeated till the hair can be easily scraped off. 



In manv countries they mix a large quantity of ashes with 

 the lime; but the only effect this mixture appears to produce is 

 that of rendering the leather less consistent than when lime 

 is solely employed. Many attribute the bad qualities of leather 

 to the too great use of lime, which has a tendency to burn and 

 render it brittle. Hence, in several well-conducted tanneries. 



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