CATECHU. 185 



Besides the trees already named, there are many 

 other of our native trees which afford tannin. Among 

 these are the elder, the plum, the sycamore, the 

 birch, the cherry-tree, the poplar, the hazel, and the 

 ash. The relative proportions which they each con- 

 tain are given by Mr. Big-gin. 



Oak bark is still, however, generally used in Eng- 

 land preferably to other substances. The demand 

 for it in this country is so much beyond our home 

 supply, that four-fifths of what is used is obtained 

 from foreign countries. But so bulky an article is of 

 very expensive carnage, and will not bear the cost of 

 freight from distant parts : it is therefore imported 

 into England only from Hamburgh, and the near 

 ports of Holland, France, and the Netherlands. 

 About 40,000 tons are annually imported into this 

 country at a duty of eight-pence per cwt. ; the 

 present price varying from b to 9 per ton, 

 according to its quality. The best is brought from 

 Antwerp, the worst from Hamburgh. The supply 

 has not, however, been kept up equal to the demand. 

 The oak bark which we now obtain is yearly deterio- 

 rating in quality ; and the time is evidently fast 

 approaching when it must be sought in remoter 

 countries, or the tanners must consent to adopt a 

 substitute. Impressed with this conviction, some of 

 the most enlightened among the leather-dressers have 

 attempted to form establishments in Dalmatia and 

 other distant parts, for making extract of oak bark, 

 with a view of diminishing the expense of carriage, 

 and enlarging the supply. 



In like manner, in new countries, where timber is 

 in such profusion as to be almost valueless, the 

 extract of the bark might be obtained, and imported 

 with advantage into the old countries. Much en- 

 couragement has been given to induce the adoption 

 of this measure in America, and subsequently in 



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