- the Alps, has hitherto divided the opinions
of geologists ; but the facts I am about to
state no longer leave any doubt on the
subject. I will first describe the varieties
of gypsum in this valley.
The gypsum of the valley of the Doron
is of two kinds, or what mineralogists
would describe as two species, — granular
common gypsum, and anhydrous gypsum.
The granular gypsum is generally snow
white ; but on the upper part of the mountains
on the western side of the valley, it
contains sulphur minutely disseminated,
which gives certain parts a yellowish colour.
On the application of heat, the sulphur
is expelled and burns.
The anhydrous gypsum possesses a greater
degree of specific gravity than the granular
gypsum, and it is harder. The specific
gravity of the anhydrous gypsum is from
2.80 to 2.83. Some of it also contains a
poition of silex. It is compact, and possesses
but a small degree of lustre. Some
of the beds are of bluish grey, and others
of a brownish red colour.
Besides these, there are beds of white, soft,
earthy gypsum, which, I have little doubt’
is nothing but the anhydrous gypsum, that.
by exposure to the weather, has combined
with water, and passed to the state of common
gypsum.
The greater part ofthe gypsum beds covers
the limestone; and where they are soft and
earthy, it is difficult to trace the stratification
or dip. This has, no doubt, given
rise to the opinion of the gypsum being
nnconformable.
Before I had discovered that the gypsum
was regularly interstratified with the
schist and limestone, I was led to the belief
that it must be so, by observing that
the gypsum was spotted with greenish talc
or steatite, which was disseminated through
all the beds, and that this talc or steatite
was of the same nature as the talcous schist
which alternated with the limestone ; and
further, that the limestone was coated with
the same steatite ; hence I was compelled to
admit that the limestone, the gypsum, and
the talcous schist, were all members of the
same formation. The mountain which
ranges along the valley opposite the baths,
has its flanks covered with gypsum, which
may be observed in various parts lying
conformably on the limestone. This mountain
is furrowed by torrents, which have
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