142 On several indigenous Plcnifs which may 



climate they bclonc; to ; whence it follow^, that there must 

 be various methods of" tanning, all which can he reduced 

 to the three methods called in Germany iceiss-s.(ihr (white 

 preparation), semisch-gar (soft preparation), and lok-gahrc 

 (tanning). I omit parchment, shagreen, and what concerns 

 skinneries. 



The first preparation is the same in these three methods. 

 When the skins are well cleansed, lime, or sand and salt 

 are made use of to take oft' the hair, and then they are 

 washed several times, &c. 



But the follow ing part of the process is not the Same in 

 these different n\cthods. We shall omit at present the two 

 first methods, which require several ingredients taken from 

 the three kingdoms of nature, such as ali\ni, common salt, 

 raw tartar, bran, meal, and fish oil ; but it is necessary to 

 enter into some details with regard to the third, in which 

 vegetables alone arc used, that serve to make a sort of lye, 

 by means of which the tanning is coiDpleted. 



This third method can be subdiN^ded again into four sorts, 

 according to the four principal sorts of leather that are pre- 

 pared with the help of different vegetables, viz. 1 . Common 

 leather; tJ. Cow's leather ; 3. Cordovan; 4. Morocco lea- 

 ther. 



Every vegetable lye fit for making leather io cither cold 

 or hot. 



The cold process is the simplest and easiest, but, at the 

 same time, the slowest ; it is used for the coarsest and 

 heaviest sort of skins, which arc put in holes, or in wooden 

 vessels, w ith oak or birch bark. 



The method of tanning with hot Ives is often very trouble- 

 some, but it is more expeditious than the former one. 

 Some sorts of leather require three v.-eeks ; others eight, 

 twelve, or fifteen days. From twe;\ty-four to tliirty-six 

 hours are sufficient for Cordovan ; IMorocco leather takes 

 seven or eiglu hours, and souietlmos from sixteen to twenty. 

 This method is as follows : The lye is poured into wocnlen 

 Vessels, toijether with hot water ; the skins are put into it, 

 and stirred i)rten. After eight days time the water is thrown 

 out, heated again, poured upon frc-^h lye, and the wliole 

 is poured upon the skins. This operation is continued and 

 sepeated until tlie vegetable parts liavc penetrated the sub- 

 Slancc of the skins so as to change them into leather; which 

 is then dried, and given over to the curriers. 



We niav remark here, that cow leather cannot be made 



as cheap with us as in Russia ; and that the scented sort 



called oulr d'.f Roussi deri\'es that property from two eiii- 



i ' pyieiiniatic 



