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The World's Commercial Products 



Birch bark produces a soft light-coloured leather specially suitable for the " uppers " of 

 boots and shoes. 



Chestnut Bark and Wood 



The bark of the common chestnut (Castanea vulgaris) contains practically as much tannin 

 as oak bark, but is rarely used for tanning purposes. The green wood contains from three 

 to four per cent, of tannin, and, like oak-wood, is employed as a source of extract in France, 

 Italy, and Austro-Hungary, where it is available in large quantities. 



" Chestnut extract " contains from thirty to forty per cent, of tannin, and furnishes 

 a firm, tolerably heavy, but rather grayish leather, which darkens somewhat when kept. It is 



imported principally from Italy and Austro- 

 Hungary, and largely used in the United 

 Kingdom as one of the ingredients of a 

 mixture employed in tanning sole leather. 



Willow Barks 

 These are obtained as bye-products in 

 the cultivation of willows to be used for 

 basket-making. They are employed more 

 especially in Denmark, Belgium, Holland, 

 and France for tanning leather intended for 

 the manufacture of gloves and similar 

 articles. The barks of Salix arenaria and 

 Salix Russeliana are most sought after for 

 this purpose. They contain from eight to 

 twelve per cent, of tannin, and yield a 

 peculiarly soft, pliable, light-coloured leather. 



Wattle Barks 

 These products, also known as mimosa 

 barks, are obtained from a series of acacias 

 indigenous to the southern parts of Australia, 

 and now largely cultivated in Natal. The 

 best Australian species are the " broad- 

 leaved " or " golden " wattle of South 

 Australia (Acacia pycnantha), the bark of 

 which may contain as much as forty to 

 fifty per cent, of tannin ; the " golden " 

 wattle of New South Wales (A. longifolia) yielding bark containing twenty to twenty-five 

 per cent, of tannin, A. mollissima (A. decurrens) and A. dealbata with barks containing from 

 thirty-six to thirty -nine per cent, of tannin. 



Little attention has been paid in Australia to the cultivation of wattles, but in Natal it is 

 done on a large scale, the species A. mollissima and A. dealbata being those most commonly 

 grown. The seed is sown in May at distances of about twelve inches in furrows six to eight 

 feet apart. When the young plants are well established they are thinned out to about six 

 feet apart. Very little care, except weeding, is then required by the plantation until the 

 plants are about three feet high, when the lower branches should be pruned off so that a 

 straight even trunk from which the bark can be easily detached may be grown. Bark may be 

 collected from the time the trees are five years old but the richest is obtained when they are 

 about ten to twelve years old. It is collected in September or December in Natal, being 

 then richest in tannin. After stripping it is merely dried in the sun, and either cut into small 



9 



WATTLE 



