n8 ANIMAL PROTEINS 



boarded, dried and glazed. They are softened down and 

 " aired off " in a cool store. 



Roller leather is a special class of sheepskin leather 

 which is used to cover the rollers used in cotton spinning. 

 The essential requirements are that a smooth plain finish 

 should be given, and the leather must not stretch or be 

 greasy. For this purpose small sheepskins with a fine 

 small grain are chosen, such as those obtained from the 

 Welsh mountain sheep. The pelts are machine fleshed, 

 short haired and often puered, but the deliming is also 

 brought about by organic acids also. The pelts are drenched 

 in pits fitted with paddles, which are used to stir up the 

 infusion occasionally. A thorough scudding is given. For 

 the smooth-grain finish it is necessary to tan in weak liquors, 

 and to give plenty of time so as to ensure complete pene- 

 tration. An oak-bark tannage is preferred, but a little 

 extract is usual to assist. The goods are coloured through 

 in paddle, like basils, and are then degreased by hydraulic 

 pressure. This should be as complete as possible, and 

 a little heat is used to assist the escape of grease. The 

 pressed skins, moreover, must be quite freed from creases, 

 and this is attained first by paddling in warm water to 

 remove sawdust, and then by drumming in fairly hot water, 

 in which they are left overnight. The skins are tanned 

 out in suspenders, taking about 3 weeks. The crust skins 

 need careful sorting, and are soaked and hand shaved. 

 They are sumached in drum, rinsed, struck out, sammed 

 and set. The striking and setting should be thorough, in 

 order to get rid of stretch. They are next " filled " by 

 coating with linseed jelly or similar material, and dried 

 out on boards in a thoroughly stretched condition. They 

 are then trimmed, seasoned and rolled with a steel roller. 

 They are then staked or perched, fluffed, re-seasoned, dried 

 and glazed. They are carefully short-haired, glazed again 

 and finally ironed. 



B. I. sheepskins are imported in a tanned condition. 

 These are soaked back and the turwar bark tannage 

 " stripped " as far as possible by drumming with soda for 



