Western Reserve chronicle. [volume] (Warren, Ohio) 1855-1921, 1872-11-20
VARIETIES OF COAL.

Prof. E. B. Andrews, State GeoIo-
gist of Ohio, delivered an address, re,
Gently, before the Cincinnati Bc@rd
of Trade, on the coal fields of Ohio, in
which he spoke as follows of the or
igin and leading varieties of coal:
Coal is formed from vegetable mat
ter. The leaves, bark and vegetable
tissues are visible in the coal itself.
Coal vegetation grew where now
found, and was not a mass of veget0-
BILE detritus carried from the land and
buried under the sea, as some think.
Coal vegetation grew in marshes and
on low Islands skirting an ancient
shore. Fishes and marine shells are
found in coal and accompanying slate.
These marshes were sometimes flood
ed, and beach-wOrn sticks carried into
the marshes and are now lodged into
the coal.
The marsh settled down and the
vegetation was buried by sands and
clay sediments, which now forms
sandstOnes and shales. This subsi-
dence was a regular and uniform thing
until arrested, and the waters were
silted up with sand and mud. A new
marsh formed, making another seam
of coal. Hence a beautiful parallelism
between the seams of coal, for each
represents a water line. The coal
thus formed is of three kinds: highly
bituminOus and cOking, splint and
camel. These pass into each other
by almost imperceptible gradatiOns.
COking cOal-formed from the veg
citation which has before burial un-
dergone the least change from deeOm-
position. A tree or branch buried in
imperviOus clay always makes bright
resinous coal. Fittsburg and Yough-
iOgheny are of this general class.
Good steam coal where it can be
stocked. . Not so pleasant for the CRATE
as the dry burning coal. 1t is good
for coke, and generally for gas.
Splint GOALS formed from vegeta-
tion more changed, which has been
more subjected to wetting and drying.
1t is generally laminated, and breaRs
into tabular blocks in fracture and
dry burning. 1t is generally rich in
carbon, and from its -cementinr
nature is especially adapted to the
blast furnace.
Camel COal-In the ancient marsh.
rs there were areas where the water
stood more or less, and there were ac-
of vegetable mud or
muck, such as we find in bOgs now
All vegetable structure is gone, and.
when dry, such muck forms a dark
and impalpable powder. Such muck
beds, in the ancient marsh, when
burned up and compressed, and btu
formed camel coal, which
shows no structure, seldom any iami-
nation, and breaks with 4 cOnchOTidai
fracture. This coal, when free from
impurities, makes a popular parlCr
crate coal, and gives to gas q high
Illuminating power.
Ash in Goals derived from the
lshes or inorganic matter in the orig
nal vegetation, and from the sedi-
nents which were brought into the
I'D coal marshes. A coal from Jack
on county gave II per cent. of ash.
from this minimum it ranges to even
% or 80 per cent, and, when exces-
i've, destroys the value of the coal.
Sulphur in Goals derived, IN
)art, from the original vegeta lion but
more from sulphates in
'cean water, decompOsed by the action
u uSCOAl pOSAuS NeScldOle udlltL.-
Part of tie sulphur is united with
ron to form pyrites or bisulphide Of
ron; part is united with the bituui-
ous matter and is volatilized in
OOking the coal, and part is found
Nth the fixed carbon of the coke. a
lere trifle is found in the ashes.
For iron making, in blast furnaces,
he more sulphur passes or in the
ooking which takes place in the top
the furnace stack the better, since
ure coke is chiefly needed. For gas
laking il is just the opposite.