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F I R S T DISCOY^ERY OF
for I had never seen any description of
volcanic rocks extending so far east of
Clermont. Walking out while dinner was
preparing, I observed a low range of rocks,
resembling heaps of cinders consolidated :
the surface was soft, but striking off a fiag-
ment with my hammer, I found that it was
internally coated with a black shining substance,
which, on examination, proved to
be indurated bitumen. Part of the rock was
spongy and cellular; other parts were compact,
and it contained the volcanic minerals,
fiorite and hyalite. Globules of the
latter were plentifully scattered on the
ground. I now perceived that this rock
was a part of the volcanic tuffa of the
country, characterised by the presence of
bitumen, which I had been informed was
common near Clermont. I felt no small
degree of pleasure in finding myself in
one of the most remarkable districts
in Europe, placed nearly in the centre
of France, and surrounded by a well-cultivated
and populous country, but exhibiting
incontestible proofs of a mighty conflagration,
th at has, at a former period,
spread over many hundred square miles.
The marks of the powerful agency of fire
V O L C A N O E S IN A U V E R G N E . 295
are so fresh, that the spectator might suppose
in some parts it liad scarcely ceased to
burn ; yet there is no record of any volcanic
eruptions having taken place since
the time when Cæsar was encamped in
Auvergne, nor was Cæsar aware that the
country was volcanic. Indeed the fact
was unknown until the year 1751, when
two naturalists, who were returning from
Vesuvius, stopped to botanise on the
mountains in Auvergne, and were surprised
at the resemblance which these mountains
presented to that celebrated volcano. They
were particularly struck with the similarity
of the lavas and minerals in both. M.
Guettard, one of these naturalists, published
an account of this discovery ; but it
appeared so extraordinary that it was not
generally believed. Future observers, however,
confirmed the truth of M. Guettard’s
statement, and proved in a satisfactory
manner the existence of ancient volcanoes
in Auvergne ; yet the attachment to particular
theories induced certain geologists
in this country to withhold their assent,
and even to question the veracity of the
accounts which had been published. Nature
fortunately remains more stable than pro