Mountain Home bulletin. (Mountain Home, Idaho) 1888-1889, 1888-10-13
GREAT SALT LAKE.
The Largest Survivor Of Once Mighty In.
land Sea,

The Largest Survivor Of Once Mighty In.
land Sea. |
The largest of the ancient lakes at
present known is Lake Bonnville, tho !
second in size has been named Lake |
Lahonton. Lake Bonneville was situ-
ated on the east border OF the Great
Basin, principally in Utah, and ex-
tended from few miles north of the
Utah Idaho boundary $50 miles south
ward. 1t flooded all the valley OF
Great Salt Lake, together with the
Sewer and Escalante deserts in
Southern Utah. 1t was l25 miles broad
and 1000 feet deep, where Great Salt
Lake is now situated. The site of the
temple at Salt Lake City was then sub
merged $50 feet
Lake Bonneville overlooked north
ward and became tributary to Snake
river. which flows into the Columbia.
At various stages is waves and cur
rents formed terraces and gravel bars
on the mountain slopes, which confined
it, These still remain as fresh and
perfect as when they were formed. and
are in part the records from which
mine the history of the ancient lake.
We know that it rose with many iluc-
| tuations until it had depth of nine
hundred feet, but did not overflow.
Then a change Of climate caused it to
contract its borders. and possibly to
become completely desiccated. In tho
lower stages of this desiccation it was
broken into separate water bodies
which must have been more or les.
saline.
Another great climatic change caused
the basin to be retilled to IA higher
level than ever before and to overflow
The water found an outlet at the nortl
end Of Cache valley, Idaho, and, as W,
have said, became tributary to tn
Columbia. The lake continued to over
flow until the waters had cut down tn,
outlet $40 feet. During this period
unless there were some peculiar condi
tions near the point of discharge, tn,
lake must have been fresh. The dis
charge of the lake was finally stoppe,
by climatic change which lowered it
surface below the bottom Of the outlet
and again the basin became partly
not wholly desiccated. This secon
low water period has continued to tn
present day, and Great Salt and Sevie
Bonneville.
The largest of these Representative
of the ancient sea is Great Salt Lake
In 1850 it covered 1850 and in 1876
., 1865 square miles. Its maximum dept
is about fifty feet and its mean dept
Approximately fifteen feet. These r,
cent changes in area are due to sma
variations in climate, similar in chal
actor to the changes which produce
, the great expansions and contraction
of the lake in ancient times. Wit
) change in volume there is change
. density; that is, the strength of th
3 brine increases with decreased are;
. aud decreases when the lake expands
/, In 1850 its waters contained abo,
+ twenty-five parts, by weight, of salin
: matter in solution to one hundre
parts of water In 1869 the salir
t matter had decreased to little le
than l5 and in 1874 to little MOI
Z than IA per cent. This change
: salinity was accompanied by increase
y area.
i The waters Of the ocean contain g.,
y per cent of total salts in solution
Great Salt Lake. therefore, in 1850, W;
six times as saline as the ocean. Lii
the ocean, too it holds many SUI
stances in solution; the principal ono
: are common salt, or sodium chlorid
and sodium sulphate; besides the
: there are small percentages of pota
l. stun. magnesia, etc.
v The influence Of temperature on IL
= solubility of certain saline substance
Q is well illustrated by this dead sea
e Utah. In summer its waters are ele;
: and transparent, but as cold wealth
y comes on it becomes milky or opale
: cent, owing to the precipitation
0 sodium-sulphate in an extremely fiji
= condition. In the dep\h of winte
: when the temperature of the atmo
/ phere above the lake falls far belo
1 freezing, an immense quantity
: sodium sulphate is precipitated and
: thrown ashore by the waves unt
t thousands of tons accumulate on u
5 beach. When the temperature ris
l the salt thus precipitated is again di
/. solved. This natural process Of fra
e tional crystilization produced by
9 lowering of temperature is instruc
= i've, and should suggest to tho
who are attempting to manufactu
: salt in Utah practical method
Il treating the natural brines in order
obtain common salt free from sodiu
) sulphate Lake Sewer is also high
u saline, and during the arid seast
y sometimes evaporates to dryness.
Occrtand Monthly.
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