Juniata sentinel and Republican. [volume] (Mifflintown, Juniata County, Pa.) 1873-1955, 1883-02-21
AGRICULTURE.

SOUTH CARoLINA's PHOsPHATES. -Th,
deposits of phosphate rscK. to the mining
of which the Sea Islands owe, TO q grea
extent, their present prosperity, extend!
from the Cooper River on the norto to the
Brood River on the south. The tract ol
land and water supposed 10 be undertake
by the phosphate stratum Is about one
hundred miles long by TWENTY-FIVE miles
wid'. Originally, l thiuk, all this tract
was under water, and the islands wert
formed by the slow growth OF sand bar:
and the gradual elevation OF the country.
Tne phosphate rocks lie on bed of clay,
not in solld sheet, as might be expected,
nut much as psvIng sIones, in the sand
bed of city s streets. The stratum is oi
the average thickness Of one loot. an
acre Will yield 1000 tons of dried phos.
phate rock fit for the market. In the riv.
ers and shsllox bays the stratum Is gener.
ally covered by thin layer of sand OF
muck, and many tons of loose rocks are
scattered widely on the almost solid sur.
face OF the main deposit. These pieces
have probably been tom up from the pave
ment by the tides. In the marshes the
ock is covered by from three to twenty
feet OF muck, and under the islands 1t is
deeply covered by sand and gravel. Ii is
only such rock as lies under the water, or
is carried by shallow deposit of muck on
the marshy ground, that is worked at pre-
sent. The process of obtaining this rock
Is called mining; but when 1t is under
water, it is more properly 5shing, as from
eight 10 twenty feet of water cover the
stratum at high tide. | judge that the
clay bed on which the phosphate rock lies
was pasture ground for large mastodons
that grazed to and fro at will over the
.narshy ground as the tide ebbed and fow-
ed. The fossil remains of sharks, clans,
oysters and mastodOns are scattered
throughout the phosphate formation.
The phosphate rock that is TO be sliiI ped
from these ports is washed clean of all
sand and muck and then dried. 1t is wash
ed by being thrown into a concave trough,
slightly inclined, In which an endless
screw ever turning forces the phosphate
upward. At the upper end of the trough
heavy stream of water enters, being
pumped up from the river or bay. The
turning of the screw loosens the material
thrown into the trough end allows the
water to work freely on the sand and
muck sticking 10 the phosphates and wash
ing them away, while the larger pieces Of
rock, unable to lass under the fiaDges Of
the screw, are forced upward in a heavy
column. The phosphates are discharged
into an inclined screen, and there whatever
sand or muck may have been held by the
moving mass OF rocks is washed of by an
tOher stream of water, and falls through
the screen into q trough, and Is carried to
the river bank and discharged into the
tidewater. The rock as it comes from the
screens falls into small cars:these, as filled
are pushed into t3e driving house, empty
Cars taking their place under the dlscharg-
ing spouis. In the drying room are four
BINS, each holding about 500 tons. These
bins have perforated iron pipes running
across them. These pipes are IN shert
sections, and fit together Ike gas mans.
They are placed into position as the phos-
pilates are dumped INTO the bins. All these
pipes connect with an oven similar to a
hOt-blast oven of an non furnace. The
bin being filed with ore and the perrora-
ted pipes being properly connected with
the hot-air oven The blowing engine begins
work, and the heated ali is blown into the
mass of wet rocks. In from twelve 10
twenty days the phOsphates are thoroughly
dried and are ready for shipment. The loss
in drying is about 20 per cent.
The phosphate beds when under water
are the property of the State. They are
thrown open TO ahy parties who nav wish
to mine on their agreeing to pay royalty
OF 81 per ton. Exclusive right to mine
under the waters of any tract are no lon.
ger granted. Thus far In 1880, some 140-
600 ions of rock have been fished up. The
royalty on this amount of rock amounts to
about one fourth of the revenue Of South
Carolina. The rock dried and ready for
shipment IS sold at an average price of IS
per ton on board ship.
The weekly pay of the negroes employed
by the companies considering Beaufort
their headquarters amounts to about $1,000.
Tie payment of this sum weekly to the
negroes explains the prosperity of the
BLACK County" Of South Carolina.