d finally see if we can
connect these with other great cosmical conditions, so as to arrive at
a consistent explanation in harmony with all.
We gain nothing absolutely from the knowledge of the so-called
"ancients" as to Volcanoes in Europe at least, where alone historic
records likely to refer to them exist. The Volcanoes of Europe are few
and widely scattered. The Greeks saw but little of them, and the Romans
were all and at all times most singularly unobservant of natural
phenomena.
Caesar never mentions the existence in France of the Volcanoes of
Auvergne, so much like those he must have seen in Italy and Sicily; and
Roman writers pass in silence that great volcanic region, though
inhabited by them, and their language impressed upon the places, as
Volvic (_volcano-vicus_) seems with others to indicate; and though there
is some reason to believe that one or other of the Puys was in activity
within the first five hundred years of our epoch, the notices which
Humboldt and others have collected as from Plato, Pausanius, Pliny,
Ovid, etc., teach nothing.
Whatever of mere speculation there may have been, volcanic theory, or
what has passed for such, there was none before 1700, when Lemery
brought forward a trivial experiment, the acceptance of which, even for
a moment, as a sufficient cause for volcanic heat (and it retarded other
or truer views for years), we can now only wonder at. Breislak's origin,
in the burning of subterranean petroleum or like combustibles, was
scarcely less absurd than Lemery's sulphur and iron filings.
Davy, in the plenitude of his fame, and full of the intense chemical
activities of the metals of the alkalies which he had just isolated,
threw a new but transient verisimilitude upon the so-called chemical
theory of Volcanoes, by ascribing the source of heat to the oxidation of
those metals assumed to exist in vast, unproved and unindicated masses
in the interior of the earth. But Davy had too clear an intellect not to
see the baseless nature of his own hypothesis, which in his last work,
the "Consolations in Travel," he formally recanted; and it only survived
him in the long-continued though unconvincing advocacy of Dr. Daubeny.
So far, the origin of the heat had been sought always, in the crude
notion of some sort of _fuel consumed_, whether that were petroleum or
potassium and sodium; but as no fuel was to be found, nor any indicated
by the products, so far as known, of the volcanic hea
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