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ions to conceal. At Bellegarde we left oui
passport, which was forwarded to Paris,
and I received an acknowledgment, which
served us on the route.
We slept at the Hôtel de la Poste, at Bellegarde,
a good inn ; and the next morning the
landlord conducted us to see a singular excavation
made in the rocks behind his house
by the river Valteline, which falls into the
Rhône below Bellegarde. The first excavation
is about one hundred and twenty
feet broad, and one hundred and fifty feet
or more in depth, with a nearly flat floor
of rock at the bottom. In rainy seasons, or
after the thawing of the snows on the Jura,
the river flows over the whole of this floor
to a considerable depth, but in drier seasons
it is confined to a narrow channel, cut
to a great depth into the rock, which opens
below and forms a tunnel, as at the Perte du
Rhone, On each side of the channel there
are large hollows like caldrons, which
have been excavated by stones whirling
round within them, as described at the
cascade of Grisey, near Aix, (vol.i. p. 148.)
The rock which forms the floor of this
excavation bears so strong a resemblance
to chalk, that few persons would hesitate
T H E V A L T E L I N E R IV E R . 271
in calling it so, from the external characters
a lo n e : it is white, earthy, sectile, and
will mark, and is as soft as some of the
English chalk near Flamborough H ead; but
when it is removed, it becomes hard, and
loses its chalky character, resembling some
of the white limestones in Savoy, which
latter frequently present the shattered appearance
o f the Kent chalk.
The section of the rocks made by the
Valteline, presents on each side —
No. J. A variegated yellow limestone.
2. Yellowish calcareous strata.
3. The lower white rock resembling
chalk, in which the channel of
the Valteline is cut.
The variegated limestone. No. 1., I was
informed, frequently contained fossils o f
the size and shape of apples, which were,
doubtless, echinites. I must leave to future
observers to determine whether the
white rock. No. 3., which resembles chalk,
really belong to the lower part of the
chalk formation.
It may be proper to state, that before
arriving at the Fort de I’Ecluse, I observed