58 ANIMAL PROTEINS 



I. The first type consists in a four-months tannage, in 

 which the liquors are worked down the yard. 



The butts pass first through the suspenders (20-40 Bkr.) 

 in about a week, and are rocked in the first liquors. They 

 next enter the handlers (40-55) rounds of eight pits, six 

 floaters and two dusters. Myrabs, or a mixture with 

 algarobilla is used as dusting material. The goods remain 

 in this set for two weeks, and should then be struck through. 

 The suspender handlers (55-65) are next entered, in which 

 they remain up to three weeks in suspension, being shifted 

 forward on alternate days. The goods now enter the layers, 

 of which four are given : first 70 for one week ; second 75 

 for two weeks ; third 80 for three weeks ; and fourth 90 

 for a month. The goods thus take sixteen weeks to tan, 

 of which ten weeks (62 J per cent.) are in layers. 



The system of working the liquors is expensive, and is 

 only possible if the butt liquors can be spent out by the 

 offal. The best or fourth layer, 90, is made from the best 

 leach liquor, 65, and extract (chestnut with some oakwood 

 or mimosa bark). After use it becomes the second layer, 

 75. The third layer, 80, is also made from fresh leach 

 liquor and extract (chestnut with some myrabs or mixed 

 extract). After being used thus it is used for the first 

 layer, 70. The used first and second layers are mixed 

 together and used partly to form the belly layers, and partly 

 to make a sharp liquor for the handlers (55-40) by diluting 

 with 40 leach liquor and adding quebracho extract. The 

 old handler liquor is run to the suspenders (40-20), and 

 finally used for colouring off the offal in drum or paddle 18. 

 The suspender handlers (65-55) are made from fresh 

 leach liquor and chestnut extract. They are afterwards 

 used to make shoulder layers. The course of the liquors is 

 shown on p. 59. 



It will be seen that fresh leach liquor and fresh material 

 are used to each set except the suspenders, which must 

 have some mellowness to ensure plumping and smooth grain. 

 L,ayer liquors are used twice only, and then (when only five 

 weeks old) pass to the handlers. These are further sharpened 



