CHROME CALF 161 



3 per cent, sulphuric acid, and are then dried out and 

 sorted. The tannage proper is in the drum, using 6 per 

 cent, dichromate, 5 per cent, hydrochloric acid, and 5 

 per cent. salt. In the reducing drum 15 per cent, hypo 

 is used and 4j per cent, hydrochloric acid. 



Whichever process of tanning has been used, the skins 

 are neutralized and washed thoroughly, as for box calf, 

 sammed and shaved. In dyeing, the skins are first 

 mordanted with a filtered infusion of leaf sumach, used 

 at 110 F. for half an hour. As fixing agent, 4 oz. 

 tartar emetic per dozen skins is then added and the drum- 

 ming continued for half an hour. The goods are washed, 

 struck out and drum dyed at 140 F. with basic colours, 

 and immediately fat liquored. In the fat liquors olive 

 oil and castor oil, with the corresponding soaps, have been 

 popular, but substitutes are now used on economical 

 grounds. The skins are next horsed a while, well struck 

 out again and dried strained. They are now finished off 

 as for box calf, except that it is usual to grain only one 

 way neck to butt and the season should consist of milk, 

 water and albumin only, though sometimes other muci- 

 lagenous matters are added. As with box calf, the finishing 

 may be varied in many ways. The skins may be dyed 

 with acid colours after fat liquoring. For pale shades 

 direct dyes are used without a mordant. For darker 

 shades of brown and red, the dyewoods are used both as 

 mordants and ground colours, and titanium salts are useful 

 as fixing agents. 



Both the " box " and " willow " finish are largely a 

 matter of public taste, and the fashion varies from time 

 to time on such points as to whether the grain should be 

 one way or two ways, and whether it should be faint or 

 bold. There are also other common finishes besides the 

 typical box grain. Glace calf is made much in the same 

 way as box calf, but there is no graining at all. The goods 

 are usually seasoned and glazed three times. Small skins 

 are preferred for this finish. Dull calf is also a plain 

 finish. The leather contains more grease, and the fat 



E. II 



