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Humboldt, Alexander von, 1769-1859

"COSMOS: A Sketch of the Physical Description of the Universe, Vol. 1"

***

[footnote] That coal has not been formed from vegetable fibers charred by
fire, but that it has more probably been produced in the moist way by the
action of sulphuric acid, is strikingly demonstrated by the excellent
observation made by Goppert (Karsten, 'Archiv fu Mineralogie', bd. xviii.,
s. 530), on the conversion of a fragment of amber-tree into black coal. The
coal and the unaltered amber lay side by side. Regarding the part which the
lower forms of vegetation may have had in the formation of coal beds, see
Link, in the 'Abhandl. der Berliner Akademie der Wissenschaften', 1838, s.
38.

[footnote] **[The actual total thickness of the different beds in England
varies considerably in different districts, but appears to amount in the
Lancashire coal field to as much as 150 feet. -- Ansted's 'Ancient World',
p. 78. For an enumeration of the thickness of coal measures in America and
the Old Continent, see Mantell's 'Wonders of Geology', vol. ii., p. 60.] --
Tr.

[footnote] ***See the accurate labors of Chevandier, in the 'Comptes Rendus
de l'Academie des Sciences', 1844, t. xviii., Part i., p. 285. In comparing
this bed of carbon, seven lines in thickness, with beds of coal, we must not
omit to consider the enormous pressure to which the latter have been
subjected from superimposed rock, and which manifests itself in the
flattened form of the stems of the trees found in these subterranean
regions.


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