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The side of the great Salè.e next to the lake h however m«ch more farrowed and
chamfteted than the little one; and the furrows, which may be deemed extremely
curions and singular, are for the most part horizontal, being, in general, about one foot
and a half in depth, and about four or E.e in height. These dimensions, nevetthekss,
gradually diminish, as the furrows get nearer the foot of the mountain : the interior part
of them is also much polished, and their salient or projecting angles much rounded,-
iu this respect greatly resembling those which I ha,e since had an opportunity of
observing in the two calcareous mountains near Yenne in Savoy, wlricii, in that spot,
serve as"» barrier or dike to the canal, into which the Rhone flows with great
impetuosity.
Unable to account for that extreme polish in the above-mentioned furrows, except
by the effect of a continual friction, it may be reasonably presumed that they owe their
origin to the work of some rapid current which existed after the first retreat of the sea,
or else at the period when it had retired from the summits of the Salêve. the Voirons,
and the Jura. Monsieur de Saussure, in his Travels in the Alps, lib. I. cap. VII. has
given so minute, and, at the same time, so interesdug and instructive a descripUon of the
first of these mountains, that nothing more on that subject is left for me to add, for I
must own, it is in consequence of having read his scientific work that I have been
aided in the observations since made, when at different times I have had an opportunity
of visiting so interesting a spot._and that my conjectures on the origin of the
lake, and the commotions experienced in that part of the Alps, though at a remote
period, have been greatly strengthened.
As to the Valley of Monetier, which is fifteen hundred feet above the level of the
lake, it Invites the botanist to it by the number and variety of Alpine plants which there
grow promiscuously,-and the lithologist, by a quantity of fragments from the primitive
mountains, mostly granite, scattered in this region. But what again appears more surprising,
are the different strata of sand and pebbles conspicuous in several parts, which
seem not to leave a doubt that this valley may once have likewise served as a drain to
the sea at the time of its retreat,—a supposition still further corroborated by the number
of horizontal farrows at present existing in the head of the little Saleve, which serve, as
it were, for a barrier to the valley.
In ascending from this gorge to the great Salêve, which is considerably higher than
the other, stands an immense piece of granite, of twelve hundred and fifty cubical feet.
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of a similar kind to those which form the primitive chain, lying on calcareous strata,
at the extreme height of eighteen hundred feet above the surface of the lake : and
again, nearly on the summit of the same mountain, at no great distance from the
chaléis, or dairies, I found, at three thousand feet above the same level, another piece of
similar kind, with very little difference from the former, as to bulk or size. Now, from
the major part of these stones having their angles rounded, my hypothesis becomes more
forcibly strengthened with respect to the manner in which those bodies have been conveyed
to the places where they are now found ; for, had they been thrown there by
volcanic operations, their angles might, in all probability, have been irregular, but surely
not worn by the effect of friction,—neither would the surface of the Saleve have been so
furrowed as it is in several parts, which doubtless, as before observed, is the work of
some rapid current.
These circumstances being duly considered, it may be concluded that my suppositions
are in fact less hypothetical than at first sight appeared, since the southern part
of the Saleve inclines considerably, forming on that side a deep sloping valley, whereas
the one next the lake has its strata much raised and abrupt,—^whieh, added to the
excessive declivity of the little Saléve, is a further proof that the whole of the mountain
has doubtless experienced various convulsions at different periods of time, and
that its strata, now so abrupt on its north-western side, originally extended considerably
towards the Jura. To this mountain, according to ail appearances, they most
probably communicated prior to the formation of the lake,—that is, before the sudden
sinking of the vaulted roof of the cavern or caverns, now occupied, or filled up
in part, by the lake itself. From these various circumstances, it may certainly be
inferred, that there was a time when the strata of the Saleve extended or projected
much more towards the north-west than at present, as the perpendicular chamfretings,
and the irregular forms so conspicuous on the same side, clearly evince, as well as thè
enormous stones, or rather immense rocks, now seen lying at its foot, resting against its
basis to a considerable height, which in many parts even exceed one thousand feet.
The thickness of these rocks, their structure, their direction, and the different species
of fossils therein imbedded, See. tend still further to show that they doubtless, at one
time, not only formed a part of the same mountain, but likewise even a part of the
vaulted roof which covered the cavern or caverns : for there is every reason to believe,
from the calcareous matter found in their vicinity, as also from the white sand