The morning news. [volume] (Savannah, Ga.) 1887-1900, 1896-09-21
THE SALT INDUSTRY.
How the Useful Article Is Mnnufac-
tured in Michigan.

From the Detroit Free Press.
The existence of salt springs in the low
er peninsular of Michigan was known to
the Indians long prior to the advent of
the white men in the country and they
were resorted to by both Indians and
wild animals. SO well known was this fact
of the presence of salt springs, that the
general government made numerous res
ervations OF lands, which were supposed to
contain salt deposits. BY the act of ad-
mission of Michigan into the union the
state was authorized to select seventy
two sections Of salt land, or land where
the presence Of saline springs indicated
the occurrence of salt deposits. On the
organization of the geological survey, the
state geologist, DR.. Douglas Houghton
made an examination, with the view to
the selection Of these lands, and in 1888
reported the results of his observations
Still these examinations were limited to
surface indications, and no extended ex-
periments were made to probe the coast
far below the surface.
However, borings were finally under
taken in several localities, resulting gem
orally in such a good measure of success
as to stimulate still further trials, devel-
oping such gratifying results, especially
in the Saginaw valley, that in 1859 the
ufacture of salt, since which period this
industry has reached its present stipend
GUS proportions, adding greatly to the
wealth and reputation of the state, and
especially to the growth of the cities and
the region in which the business is car
ried on.
The origin of these deposits is not
known; whence the waters lying so far
beneath the surface derive their saline
property there Is no apparent means Of
determining, nor is the boundary of the
surface known beneath which these de-
posits of brine may be found. The Mchi
gan salt group has a wide extent in the
state, though thus far the greatest sue
cesses have come from the Saginaw val
ley Where the lowest horizon is found in
the salt group the brine is found to be the
strongest, greatest in amount and best
in duality. 1t is for this reason that salt
wells in the Saginaw valley have proved
to be more valuable than elsewhere. 1t
is the region in which the greatest de-
preston occurs. The salt group here
lies at a depth reaching to more than
a thousand feet below the surface of the
lake. At what depth below the surface Of
the lake this brine Is found the writer is
unable to state. OF one thing there Is an
apparent certainty that the supply of the
brine is inexhaustible. The extent to
which the manufacture of salt in Michi-
gan may be carried on is one of cost and
demand The brine may be assumed as
existing in quantity far in excess of our
ability TO diminish It,
OF the two models of securing the evapo-
ration Of the water, either by the ap-
plea tion of solar or artificial heat the
latter is the method mainly resorted TO
in the Saginaw valley. Solar evaporation
is effected by exposing the brine in shall
low wooden watts. Such watts as are used
are about eighteen feet square and six
inches deep. They are supported on posts
above the ground and are provided with
a roof which is readily moved on the watts
or off from them to cover the brine from
the rain or expose 1t to the sun, as re-
quired. The process fs begun in March,
and the contents removed In July, the
product of the second filing is taken out
Sept /, and the third and final removal
occurs the last of October The annual
product of a single vat of this size is
fifty bushels
A kettle block contains fifty or sixty ket-
ties set close together and in rows inclosed
in stone work or brick work. A launder
connects with a cistern kept filled with
brine, and runs along between the rows
of kettles, and from this launder the
brine Is drawn out into the kettles by
opening lateral spout When 20 per
cent of the water has been boiled away,
the salt is dipped out into a basket or
sieve to allow the water to run out of 1t,
after which a sufficient time-about two
weeNs-it is ready to be put into barrels.
But the greatest advance in the way of
cheapening the cost of the salt production
has been achieved by the use OF steam to
afford heat for evaporation For this
purpose the exhaust steam of the great
mills of the Saginaw region is used.
Pans are also made use of, a so-called
pan block consisting of a settler" pan,
and packing-room inclosed in the same
building. The brine is drawn from the
settler into the pan,to the bottom of which
the fire is directly applied, making the
evaporation very rapid, and causing the
salt to form continuously.
The salt business in Michigan has swol-
len from the manufacture in 1860 Of 1000
barrels to 1887 .2S6 in 1895.
The estimated capacity of the 11S firms
now engaged in the manufacture Of salt
In this state is 5,s50.00O barrels per year.