1' i
22 GEOLOGY OF
them, .was so much overcome by fright,
that when he arrived at the summit, he lay
for some minutes speechless, with his face
on the ground, and when he recovered, he
declared that not all the gold in the world
would tempt him to ascend a second time.
I mention this circumstance, as it may be
useful to travellers to know, that there are
two paths over the Col de Ferret, one of
which is not safe.
I propose to coniine any farther observations
on the geology of Chamouny, principally
to the secondary rocks. Saussure, after
a laborious investigation of many years,
has so fully and ably described the rocks
of Chamouny, called primary, that he has
left little for subsequent observers to add
or to correct. The terms which he employed
are not, however, precisely the same
as those used by modern geologists, and
require some explanation. The veined
granite [granit veine), which forms a large
part of the granite of the Alps, is not (as
might be supposed) gneiss, but may, I
think, be properly described as an incipient
passage of granite into gneiss, owing to the
laminag of mica approaching to a parallel
arrangement, instead of being scattered in
every direction, as in common granite.
This it is which gives it a veined appearance,
when broken transversely, but the
mica is not so distinctly separated from the
felspar, nor so abundant as in common
gneiss, though specimens may be got from
it, which owing to a greater quantity of
mica, might pass for gneiss. The name
is however of little importance, but it is
well deserving notice, that this peculiar
structure appears to have influenced the
form of the granite en masse, and to have
divided it into beds, or, if the term be
liked better, into strata. The direction of
the strata is the same as that of the veins
of m ic a ; and when the beds, or strata, of
granite are vertical, the veins are vertical
also. Were it not for this circumstance, it
would be impossible to say that the perpendicular
strata of granite were not intersections
of granite by perpendicular and
parallel fissures. But when these plates of
oranite are seen associated with vertical, or
highly-inclined strata of schist and sandstone,
having the same range and dip, we
can no longer doubt that the sandstone,
schist, and strata of granite, have all undergone
the same change of position, and
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