The Opelousas courier., 1905-07-22

lIlDutlh5 markets, anu, necessarily, W
the high cost of transportation. Elk
cept for a small local demand from
%ranchers, the yield of these deposits is
too minute to figure in general statis-
teal records.
The vast amount of salt consumed
On the Pacific Coast is derived, there
fore, from the sea by evaporation in
quantity only limited by the demand.
The cost of evaporated salt is but one
fifth of the lowest rate of transporta-
ton on rock salt from the nearest
source of supply to the most accessi-
BILE ocean port.
The locality which enjoys q practi-
cal monopoly of salt making OF the
Pacific Coast of the United States is
Alvarado, a town of Alameda county
and twenty miles from San Francisco.
At this point, which lies on the east
side of the southern extension of San
Francisco Bay, exist certain peculiar
tiles in the lay of the land which, uni
ed with climate and a favorable char
acter of the soil, combine to make the
locality especially adapted for this
particular industry.
Long intervals of cloudless skies,
the low humidity and high temper
ature all favor rapid evaporation,
while the soil, a stiff clay, is we'll
adapted for levees and making water
tight reservoirs. The land would be
submerged at high tide but for the
levees that prevent. The highest
point in all this tract of 1000 acres,
two miles from mean tide level, is not
more than four feet, the low altitude
part, to fill with sea water by gravity
alone. Moreover, the southern section
allowing the reservoirs, for the most
of the bay is contaminated by no con-
siderable affiuents to dilute with sup
plies of fresh water the sadness
which comes in with the tides of
ocea
The largest as well as the most
thoroughly equipped of the several
corporations engaged in the business
is the Continental Salt Manufacturing
Company, which has thirty reservoirs.
covering 1000 acres. This company
has constructed from first to last u
miles of l~eyees, 1900 feet of fumes
and 7 IL miles of bitches. A slough
meanders through the tract, which is
navigable for vessels Of considerable
draught and affords excellent and
economical facilities for shipping. .
A large mill, well equipped with the
best machinery for washing, drying,
grinding, sitting and boiling the fin
ished product Is a prominent feature
of the works. Twenty Dutch wind
mills and two Chinese pumps raise
altogether 200, 900 gallons of brine
each minute. The entire plant pre-
sents to the observer a miniature
Netherlands with the distant ships on
the bay appearing as though floating
in the air. The transformation of
this low, half-drowned district, cover
ed for the most part with a dense
growth of swamp vegetation, has been
effected by a large expenditure OF
time, labor and money.
To eliminate the vegetation re-
quires three years time. First the
levees have to be built and the in.
! closed lands kept flooded for thirty
six months, when the plants die to the
roots and the trace of iron left in the
soil is washed out. Afterwards the
bottom of the new reservoir is first
leyeled and then made tight by
heavy rollers being drawn over the
surface, securing a strong and firm
foundation. Fumes. sluices and
bitches to connect with other reser-
voirs are then constructed and the
new Enclosure is ready for salt max
ing. The manufacture of salt from
ocean water is a constant progression
from one reservoir to another, trans.
fer being made as the brine reaches a
certain density to the next. Reser-
yoir No. 1 covers 305 acres and IS
surrounded by a four foot levee. It's
outward boundary is upon a slough
flowing from the bay. AS the tide
| rises twelve gates are opened and
allow the sea water to flow In to a
depth of three feet. The gates are
| then closed. The average strength of
the sea water is from 4 to I deg. and
| remains in reservoir No. 1 until the
strength increases to 80 deg. By
means of windmills reservoir No. l
is emptied into reservoir No. 2, and
the brine is exposed to the heat OF
the sun until it reaches a density OF
| SO to 60 deg, which may take three
weeks.
The brine is then pumped into res
| er4oir No. 3, where it attains a
strength of rs to 80 deg. II then goes
into reservoirs Nos. 4, $, 6, Z and 8.
known as settling ponds, where the
brine voluntarily parts with the lime
which it contains and becomes almost
a saturated solution at a strength OF
80 deg. 1T is then conveyed to the
twenty-five salt ponds where it is e
posed to the fierce heat of the sun,
and in about twenty days the salt is
deposited and the pickle allowed to
run off. Two crops are gathered, one
each in August and October. After
precipitation the salt remains exposed
for a few days, when it is first piled
in heaps and them wheeled in barrows
into great pyramids on the banks.
Boards are laid upon the bottom of
the reservoirs to prevent the ground
from being cut up by the wheels.
Dump cars running on temporary
tracks are also employed. After the
| salt is removed the reservoir is care