SECTION VI. BELTING LEATHER 



THE manufacture of belting leather is well illustrated by 

 the tanning and finishing of " strap butts." In general, 

 the tannage presents many points of great similarity with 

 the tannage of sole leather ; indeed, the resemblance is so 

 close that in some factories there is little difference observed, 

 and the currying and finishing operations are relied on to 

 produce the desired difference in final results. Nevertheless, 

 there is considerable difference in the type and ideal of the 

 two leathers, which may be expressed in trade parlance as 

 a greater " mellowness " for the belting leather, and in the 

 best methods of manufacture this fact is in evidence 

 throughout the whole process of manufacture. 



In liming, there need be little difference between sole 

 and belting hides, and a sharp treatment of 9-10 days, by 

 the three-pit system, with a day or two extra in the coldest 

 weather, would meet ordinary needs. For the conservation 

 of hide substance and for the saving of time a shorter liming 

 is sometimes given, in which more sulphide is employed 

 than is usual for sole leather. Even the very short processes 

 of liming, i to 3 days, which involve the use of strong 

 solutions of sodium sulphide, have been successfully employed 

 for belting leather. The tendency to harsh grain with such 

 processes is not so serious a defect with belting as with sole 

 leather, and can be minimized by careful deliming. American 

 and Continental factories tend to favour the use of those 

 quick processes which employ warm water in addition to 

 sulphide. The hides after a short liming in sulphide limes 

 are immersed in warm water, which greatly accelerates both 

 the chemical and bacterial actions. For example, after 

 about 3 days' liming, in which both old and new limes are 

 B. 5 



