The Principles of Leather Manufacture
CHAPTER X.
_WATER AS USED IN THE TANNERY._
Impurities of natural water -- Hardness -- Soap test -- Temporary hardness -- Clark’s softening process -- Archbutt and Deeley’s softening apparatus -- Other appliances -- Effect of temporary hardness in tanning and dyeing -- Permanent hardness -- Boiler scale -- Mud -- Iron -- Alumina -- Soda -- Copper, lead, etc. -- Sulphuric acid -- Nitrates and Nitrites -- Chlorine -- Carbonic acid -- Silicic acid -- Effect of hardness on plumping -- Peaty waters PAGE 93