Watertown republican. [volume] (Watertown, Wis.) 1860-1906, 1873-05-14
SALT WATER LAKES.
Their Origin anh Chnracter.

The origin Of all salt water lakes
cannot be accounted for, but for some
OF them the evidence is clear, and It is
plain to see why they are salt. The
principal minerals forming the rocks
of the earth's crust are SILICA, alumina,
lime, potash, soda, magnesia, peroxide
of,lron, &c. Rain water takes up from
the atmosphere and the earth's surface
a small proportion Of carbonic acid,
and thus acquires the power of dis
solving certain of these minerals as it
percolates through the rocks, notably
lime, which 1t carries away in the form
of bicarbonate And thus the water
of all springs is charged more or less
with mineral ingredients, though these
may be recognizable only by the skill
of the chemist.
Salt lakes, though not go numerous
as fresh water lakes, occur in large
numbers in certain regions. The Cas-
plan Sea, with an area as large as Spain,
the sea of Aral, and vast number
among the mountains and tablelands
north of the Himalaya, the Dead Sea
in Syria Lake Utah, and neighborlng
lakes among the mountains on the
among the mountains of South Amer
lea, and in the interior of Australia, are
examples of large water lakes. 1t
will be noticed that all these lakes lie
in an area of inland drainage, that they
have rivers running into them, but that
they have no outlet. The Black Sea is
fresher than the Mediterranean, by
reason of the greater supply of fresh
water furnished by the rivers, and
Edward Forbes showed that this fresh
ening has caused certain shells of the
Mediterranean species to assume
monstrous shapes. The Caspian IS
still fresher, and it's fauna and fossils
in recent deposits in the neighborhood
prove it to have once had connection
with the Black Sea, from which
it has been separated by changes
in physical geography; it was
then salter than at present, but it is now
growing salter again every year, and
the fauna now inhabitiug it's waters
have likewise considerable affinities
with Northern Sea types. Its surface
level is 83.5 feet below that of the
Black Sea, while the suface OF the
Dead Sea is 1,300 feet below that of
the Mediterranean. In all cases where
river flow into depressions of the land,
however these might have been formed
(oscillating movements Of the earth's
crust might form such large ones as
the Caspian basin,) carrying with them
certain salts in solution, II the lake
have no oyerfiowing river, the water
must be carried away by evaporation,
IN which these salts will be left behind,
and the remaining waters become more
and more saturated. 1t is stated that
crystals of salt have been brought up
from the Dead Sea, and on the shallow
waters on the coasts evapO1ating in
summer saline incrustations are left.
The same water which flows through
the Sea Of Galilee, fresh water lake,
renders the Dead Sea one of the most
remarkable salt lakes in the world
And in this and all similar cases ac-
emulation Of salts will go on till the
saturation point Is reached, and then
precipitation will commence. The
region to the north of the Himalayas
is omparatively rainless, owing to the
mountains condensing the moisture
carried by the south winds, and the
rivers consequently do not carry into
the lakes sufficient water to make them
overflow their boundaries, hence they
are salt. Lake Baikal, with an outlet
to the sea is quite fresh. For SINH
lar reason the moisture from the south.
west wind being condensed in great
parts by the Sierra Nevada, the lakes
which lie in the great plains and table
lands to the east of that range have
not sufficient supply of water to cause
them to overflow, and consequently
they are not salt, and are continually
becoming salter. Mature.