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Various

"Scientific American Supplement, No. 803, May 23, 1891"

The countries that consume the greatest amount of pine
bark are Austria, Germany, Russia and Italy. The tannin contained
varies from 5 to 16 per cent. Its use is almost wholly confined to the
handlers, as its weight returns are not so satisfactory as oak or
valonia. In case it should be used for layers it is always in
combination with some better weight-giving tannic. For upper leather
its use is limited.
The bark is always peeled from the felled tree, and often the woodman
accepts the bark in part payment for his labor; he then sells the bark
to the tanner or agents who go about the country collecting bark. It
is generally very nicely cleaned. I would here like to correct a
mistake which tanners often make in their estimations of the value of
barks. A tanner usually buys the bark of southern-grown trees in
preference to that of trees grown in northern countries, as it is a
common idea that southern vegetation contains more tannin than that of
the north. This is a fallacy, as has not only been proved by careful
analyses, but may also be found to be an incorrect conclusion after a
moments' thought. Those trees which flourish in southern countries
grow very rapidly, and as tannin is necessary to the development of
leaf structure, etc., it is absorbed to a greater extent than is the
case with the slower-growing tree of the north.


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Dzieci Niczyje Rodzic Po Ludzku Nasze Dzieci Krwinka Fundacja Avalon