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CHAPTER VIII. 



TANNING MATERIALS. 



The most generally used material for converting the skins 

 of animals into the valuable economic article leather, is the 

 bark of the common oak, and various less common species 

 of the same genus. Several of the tanning materials are 

 also used in dyeing. 



Oak Bark. Quercus pedunculata. (Nat. Ord. Cory- 

 lacece, Mirbel.) 



This familiar tree needs no description. Some there are 

 however who regard it only as furnishing material for those 

 " wooden walls" which are both the glory and defence of 

 our country ; but valuable as is the timber of the oak-tree, 

 its bark is also of great utility, furnishing perhaps the best 

 known material for tanning hides and skins. This astrin- 

 gent property, found in all parts of the oak-tree, was known 



