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Humboldt, Alexander von, 1769-1859

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

Daubeney, op. Cit., p. 444.] -- Tr.

In a much higher volcano than that of Teneriffe, the Rueu Pichincha, other
relations occur
p 231
which approach more nearly to that of Vesuvius. Among all the volcanoes
that I have seen in the two hemispheres, the conical form of Cotopaxi is the
most beautifully regular. A sudden fusion of the snow at its cone of
cinders announces the proximity of the eruption. Before the smoke is
visible in the rarefied strata of air surrounding the summit and the opening
of the crater, the walls of the cone of cinders are sometimes in a state of
glowing heat, when the whole mountain presents an appearance of the most
fearful and portentous blackness. The crater, which, with very few
exceptions, occupies the summit of the volcano, forms a deep, caldron-like
valley, which is often accessible, and whose bottom is subject to constant
alterations. The great or lesser depth of the crater is in many volcanoes
likewise a sign of the near or distant occurrence of an eruption. Long,
narrow fissures, from which vapors issue forth, or small rounding hollows
filled with molten masses, alternately open and close in the caldron-like
valley; the bottom rises and sinks, eminences of scoriae and cones of
eruption are formed, rising sometimes far over the walls of the crater, and
continuing for years together to impart to the volcano a peculiar character,
and then suddenly fall together and disappear during a new eruption.


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