The news and herald. (Winnsboro, S.C.) 1877-1900, 1883-03-10
AGRICULTURE.

SoUTn CARoLlNA'e PMospitATEs. Tho
deposits OF phosphate rocs. to the mining
OF which the Sea Islands owe, to d great
extent, their present prosperity, extends
from the Cooper River on the norto to the
Brood River on the south. The tract of
iand ana water supposed TO be undcrlaid
ny Tho phosphate stratum Is about one
hundred miles long by twenty-five miles
w!d". Originally, l thiuk, all this tract
was under water, and the islands were
formed by tho slow growth Of sand bars
ana the gradual elayation OF tho country.
Inc phosphate rocks lie on q bed of clay,
not IN solld sheet, as might be expected.
eut much as paving stones, in the sand
oed OF city's streets. Tho stratum is of
the average thickness of one loot. AN
acre Will yield 1000 tons of dried phos-
rhate rock fit for the market. In the riv-
ers and shallow bays the stratum ls gener
ally covered by thin layer Of sand or
muck, and many tons Of loose rocks arc
scattered widely on tho almost solid sur
lace OF the main deposit These pieces
have probably beon tom up from the pave
mcnt by The tides. In the marshes the
rock IS covered by from three to twenty
leet OF muck. and under the islands 1t is
deeply covered by sand and gravel. 1t is
only such rock as lies under the water, or
is carried by shallow deposit OF muck on
tue marshy ground, that IS worked at pre-.
sent. The process Of obtaining this rock
IS called mining; but, when It is under
water, 1t Is more properly 2shing, as from
eight to.tWenty feet of water cover the
stratum at high tide. judge that the
clay Ded on which the phosphate rock lies
was pasture ground for large mastodons
that grazed to and fro at will over the
.narsny ground as the tide ebbed and flow
Gu. Inc fossll remains Of sharks, claus,
oysters ana mastodons are scattered
throughout the phosphate formation.
The phosphate rock that Is to be slippcd
from these ports is washed clean of all
sahd ana muck and then dried. 1t is wash
Gu ny being thrown into concave trough
slightly inclined, IN which an endless
screw ever turning forces the phosphate
upward. at the upper end of the trough
Il heaVy stream of water enters, being
pumped up from tho river or bay. The
turning OF the screw looscns the material
thrown into the trough nnd allows the
water to work freely On the sand and
muck sticking TO the phosphatcs and wash
ing them away, while the larger pieces of
rock, unable to pass under the fapgcs of
the screw, are forced upward in 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 trough, and Is carried to
the river bank and discharged into the
tidcwatcr. The rock as it comes from the
screens falls into small cars;these, as filed
are pushed into tae driving house, empty
cars taking their place under the dlscharg.
ing apouts. In tho drying room are four
BINS, each holding about 800 tons. These
olns have perforated iron pipes running
across them. These pipes arc III short
sections, and tit together like gas mans.
They arc 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 iron furnace. Tho
bin being filed with ore and the pcr'ora-
ted pipes being properly come cted with
the hot-air oven the blowing engine begins
work. and the heated air is blown into the
mass Of wet rocks. In from twelve 10
twenty days the phosphates are thoroughly
dried and arc ready for shipment The loss
in drying is about 20 per cent.
The phosphate beds when under wafer
are the property OF the State. They arc
thrown open to any PARTIES who may wish
to 'uinc Oh their agreeing TO pay royalty
OF 81 per ton. Exclusive right to mine
under the waters Of any tract arc no lon.
ger g'antcd. Thus far IN 1880, some 14O-
600 tons Of rock have been fshcd up. The
royalty on tins amount of rock amounts to
about one fourth OF the revenue OF South
Carolina. The rock dried and ready for
shipment IS sold at al average price OF $8
per ton on board ship.
The weekly pay of the negroes employed
by the companies considering Beaufort
their headquarters amounts to about $1,000.
The payment of this sum weekly to the
negroes explains the prosperity Of the
"B!ack County" Of South Carolina.