Bismarck weekly tribune. [volume] (Bismarck, Dakota [N.D.]) 1884-1943, 1899-06-23
THE MAKING OF SALT.
ANCIENT AND MODERN SYSTEMS OF
REDUCING BRINE.

REDUCING BRINE.
The Methods Used Include Solar
Evaporation, Kettles aud Open and
Vacuum Pans-Salt Beds of Ameri-
ca and Their Ancient Origin,
which salt is obtained, natural brines
and solid deposits. A number of theories
have been advanced to account for the
latter. The general impression among
scientific men is that rock salt has been
formed by evaporation from ancient seas,
which had become incloscd in some way.
In confirmation Of this notion it is point
ed out that deposits are being made to-
day Mt the bottom Of several we'll known
salt lakes. But doubts have been ex-
pressed as to the applicability of the ex-
PLANTATION to such thick strata rs those at
Stassfurt, Germany, 1880 feet deep,
and ut Sperenberg, near Berlin, 5000
feet thick. However this may be, the
substance is found, in greater or less
purity, in all parts Of the world. The min
erals associated with it are those which
are apt to exist in the ocean. What is
commonly known as "salt" is principally
chloride Of sodium. But chlorides of
lime and magnesium, sulphates Of lime
and magnesium and even minute guam
titles Of iodides and bromides are usually
mingled with the chief constituent.
For a long time Turks island, in the
West Indies, was a copious contributor to
this country's supply Of rock salt. But a
number of mines are now being worked
in the United States. The most famous
at present are those at Livonia, N. Y.
The salt is taken out in solid chunks,
ground, passed through sievcs of differ
ing mesh-to be graded according to
coarseness-and put up in bags or bar
rels. There is a famous deposit in Lou
isiana much nearer the surface Of the
ground and more easily worked, which
will be an important producer some day.
There are many salt deposits in this
country which are made available, not
by mining, but by the pumping of brine
from their vicinity. Through a large
part of Michigan, for instance, and from
the central part of New York state out
as far as Buffalo, there are beds varying
III ASAAC IOl4 LIZ " OOO lGCC anu Nv.
ing from 600 to 1900 feet below the sur
face. All through these two regions, as
well as in northern Ohio, wells have been
sunk, and the brine is pumped up like
oil. Fresh water springs supply the wa
ter, no doubt, and this, flowing over and
through the solid salt, dissolves the lat
ter n puts it within mans reach. In a
few places there are salt springs which
nio0f fh0ivs s,ioor.o1 1o5o- a,,:l, -,:Al,>.k
coaxing.
There are five principle methods of
treating brines in order to get the salt
from them. One Of the oldest systems
is that SO extensively employed at SYRIA
cuse. The brine is poured into enormous.
shallow, wooden watts and exposed to the
sun and wind to dry. Whenever there is
q rainstorm, covers are drawn over them
to exclude additional water. Precautions
are also taken against the admission of
dirt. The product obtained in this way
is called "solar salt" Owing to the slow
ness of the evaporative process the
grains thus formed are coarse.
To hasten matters artificial heat is Of
ten used. For instance, rows Of kettles
are arranged so that coal fires may be
maintained under them. AS the water
boils off the salt crystallizes in the bot
tom OF the receptacle. BY regulating the
degree Of heat applied and providing for
marked differences of temperature in two
sets Of kettles, grains Of different sizes
can be secured, the incl ones resulting
from the more rapid evaporation. This
method is m ancient one.
In Wyoming county, N. Y, artificial
heat is used in another way. Metal pans
about 125 feet long, % feet wide and
perhaps 2h feet deep, are warmed by
furnaces directly under them. Coal is
used in the latter. The heat being up.
piled directly, the system is known as
the "direct heat" plan. It is further
characteristic of the process that it is
conducted with open pans. An indirect
mode Of bringing the heat to bear on the
brine is to line the watts, which are small
er receptacles than those just described,
with steam pipes, which run around the
inner edge Of the same and transmit
their heat to the fluid. The. indirect heat
apparatus is called a "grainer."
Finally it has been found feasible to
save fuel and obtain a purer salt by in
closing the brine in a tight vessel from
which the air has been almost entirely
exhausted. This is called a vacuum
pan" 1t is a well known fact that evap-
grafton takes place at a lower tempera-
ture when the air pressure is reduced
than at ordinary pressures. This is the
reason why water boils at a lower tenn
perature on a mountain top than on a
plain. In the vacuum pan the work can
be done by heating the brine to only 112
degrees. The product of the vacuum pan
process is "a beautiful article and COM
mands a higher price than other salts.
The grains form in cubes instead of
flakes. The salt obtained from the indi-
rect heat (steam pipe) system is also Of
an excellent quality.
Salt had been obtained from sea water
in many parts Of the world. Owing to
the foulness Of the drainage into the
ocean from the land it is desirable to be
particular about the source of supply.
Moreover. there are regions in the trop-
les where the salinity of the water is
greater than it is in older climates and
where the same amount of labor will
yield a larger quantity Of solids. The in
dustry is carried Oh, however, in a mod
est way on Cape Cod and in Bristol,
N(.---aHIl - Z =