Cheraw gazette and Pee Dee farmer. [volume] (Cheraw S.C.) 1838-1839, 1839-01-02

| cheerfully comply with your request
tNat would commun cc 4 simple melh-
Cd OF de:ermnny the nature and relative
value of marls and calcareous deposiles
generally, for agricultural and other pur.
poses.
During the present session Of the Leg.
islature opportunity has been afforded
me Of examining many such specimens
from very different parts of the State, ard
have no hesitation in saying that their value
in agriculture renders them of more i'm.
portance to its welfare, than almost any
other mineral treasure which could be dis.
covered. Not few Of them, too, are sus.
ceptibIs of easy conversion into lime of good
quality, for agricultural purposes.
There is too little uniformity in the ex.
ternal character Of these maris 10 enable
US to detect them. They vary much in
color, passing from almost pure whIlo to
difIeren, shades ofgrey, yellow and brown
occasionally they consist 10 greater or
less extent Of shells Or their fragments
connected by foreign matter, but more fire.
quently they exhibit no appearance OF or.
ganic origin. a
The simplest mode Of determining the
nature Of such a substance, is 10 drop a
fragment oft into small quantity Of dilute
nitric or muriatic acid, when rapid effer-
vesence lakes place and continues until
the mass is either entirely dissolved or the
undissolved portion remains as e fine pow
der. This effervcSence is due 10 the es.
cape of carbonc acid from the carbonate oi
lime, which is the valuable constituent OF
lhe mari, and its amount and violence will
serve for rough estimate of the quantity
of that substance present
But much closer approach to accuracy
is easily attainable, aud requires no means
which are not like to be- found IN every
planters house. All that is necessary is
little muriauc acid, which need not be pure
a good pair of medicine scales, and a
very thin and light SIX ounce vial 10 make
the assay, portion of the mari reduced 10
fraemets about the size ofa pea IS to- be
thoroughly dried before the fire and one
hundred grains accurately weighed out.
In the mex; place the vial containing
about an ounce of mur:atic acid and an
equal weight or water, is TO be placed IN
one Of the scales and accurately counter
poised. To the counterpoise weight OF
100 grains is added. The vial OF acid be.
ing now removed from the scale, the irag.
menls of mari are to be added TO it at In
tcrvals until the whole has en- introduced.
To prevent small portions Of the liquid
from being thrown out of the vessel during
The ef;.rvescnce, it SHOULD be inclined at an
angie ofabout 45 dcsre 's.-When The eff:
ervesence has entirely ccas.d, the gas
above the Iiquil is TO be removed by gently
blowing into /, two or three times with a
bellows, and The bottle aad its contents are
! to be returned to the scales. A loss Of
weight dae 10 tlc carbonic acid wich has
escaped in gaseous form, will be observ'
cd. Is amount is determined BY the weight
necessary to restore the equilibrium, and
from it the quantity Of carbonate OF lime
n the hundred parts is easily culca'ed by
the following rue Multiply the loss OF
weight by 100 ard divide by Al. The
quolient is the answer.
This whole process, which is Of very
easy performance, and occupies not more
than fifteen minutes, will give result sutfi'
ciently true for all practical purposes
Very respectfully,
Your obd'l. sery'
w. H. FLLETT.