very little dip where the first junction is
seen; but about a mile below, you meet
with the limestone again in junction with
the sandstone, and thrown into a vertical
position. The workmen that I met with
near the mouth of the gallery, said they
always found sandstone below the limestone,
and they considered it as the lowest
bed in the country; but this is obviously a
mistake. The sandstone or molasse on
which the limestone on this part of Savoy
reposes, or which is subordinate to the
limestone, is composed of smallish grains
of quartz and chlorite, pretty equally mixed.
In the sandstone of les Echelles, which
I got from its junction with the limestone,
there were some particles of rose-quartz
and mica. It scratched glass strongly when
rubbed upon i t ; but when put into dilute
muriatic acid, it effervesced violently, and
became friable, owing to the solution of the
calcareous cement, by which it appears,
from this experiment, to be agglutinated.
The molasse, which is interstratified with
limestone, and associated with coal on the
Lake of Annecy, also effervesced; but the
particles being smaller, it appeared nearly
homogeneous when examined without a
lens. It has been recently stated that the
molasse of the Alps belongs to the same
formation as the sandstone above chalk
near Paris. There may be sandstone of that
formation in the canton of Berne ; but the
molasse or sandstone in this part of Savoy,
I am well convinced, is a member of formations
that are lower than chalk. It is possible,
however, that beds of this molasse
may have been worn down, during the great
destruction of the strata that has evidently
taken place since they were deposited, and
from the debris of this sandstone, upper
beds may have been formed covering strata
that are above chalk. The molasse which
covers the bones and teeth of the mastodon
and other large mammalia, near
Alpnach, nearly resembles that in this part
of Savoy; but the particles are smaller and
more intimately mixed.
The great wall of limestone o througoh which
the gallery is cut, was once joined to the
mountain behind it, though it is at present
separated from it by a deep chasm, at the
bottom of which the old road is carried.
This was apparent in walking down this
road, for I observed the strata-seams in
the rocks on each side, to correspond.
N 3