The weekly Ottumwa courier. [volume] (Ottumwa, Iowa) 1857-1872, 1860-02-16
Geology Of Wap-
clio County.

Coal. BY far the most valuable mineral
product of Wapelo county is stone coal, OF
which it has an abundant supply for the use
of dense population for centuries to come.
BY reference to the map, it will be seen
that nearly the whole of Wapello county is
underlaid by rocks belonging to the coal
measures, and it is quite certain that more
than one-half of its entire surface is under
laid by workable coal seams.
The mining engineers of Europe are said
to allow one million tons of coal per square
mile for every foot in thickness of workable
COAL Allowing one-half the surface Of this
county to be nderlaid by three-foot coal
seam, we have six hundred and forty-eight
million tons of coal as the product of this
county alone. This is undoubtedly an under
rather than an over estimate of the resour-
ces of this county in mineral coal. A con-
siderable portion of the county is underlaid
by at least two coal seams, averaging from
two to five feet in thickness each. When
railroad facilities shall render coal-mining
profitable in this region, these coal-seams
will be sought out and opened and the
time will undoubtedly come, when the mining
privilege of a large portion of this county
will be worth more per acre than the best
farming lands are now held at. ...
The abundant supply of timber in this
county has rendered the local demand for
coal exceedingly limited and it will require
increased facilities of transportation, and a
better market, to fully develop the mineral
resources of this region. -...... .....
Building-stone Some portions of the
county, especially the northeasternand south
ern parts, are but poorly supplied with good
building stone; but along the Des Moines,
from the mouth of Sugar creek to the north
west corner of the county, an abundant sup
ply may he obtained from the Concretionarv
limestone. This bed furnishes compact
regularly be lded grey limestone i'm strata
from six to twelve inches thick, which is ex-
ceedingly durable, and well adapted to all
the ordinary uses for which building rock is
required. Some Of the Coal-measure sand
stones may also be used for foundation walls :;
but they require considerable care in their
selection, ifrequi ed to withstand the action
of frost and moisture. ......
The band of Coal-measure limestone which
outcrops in the vicinity of Dam No. II has
been qusrried extensively for the construc-
ton of the lock at that point, and appears
to be a durable rock. 1t contains a good
deal Of sulphate ofiron disseminated through
it in crystals, which dlsintegrate readily on
exposure, leaving cavities in the rock.
Lin'estones for Lime. The only rock in
the county suitable for the manufacture OF
quicklime is the Concretionary limestone
abe ve mentioned, which affords an excellent
material for that purpose, and great abln-
dance. Its extent of outcrop is given under
the head of Bui!ding-stones in the foregoing
section. .
Iron Ores The brown hematitic ores of
iron occur in various parts of the county in
connection with the Coal measures, but no
bed has yet been found of sufficient thick
ness to Justify the erection of furnace.
Hydraulic Limestone Some of the bands
of Coal-measure limestone which outcrop in
this county appear to possess hydraulic prop
critics, but they are usually too tim to be of
much value.
Fire Clay Beds of good fire clay may be
found at many points in the country, under
lying the coal seams, and only require a
small outlay Of capital to ,.bcome source of
wealth to the county.
Clay and Sind for Brick These materials
are abundant in all parts of the county, and
may be obtained at almost any point where
circumstances make it desirable 20 manufac-
ture the article. Good clay for this purpose
may be obtained Immediately below the soil !;
and sand is abundant in the lower portion of
the Drift deposit, end is accessible on nearly
all the streams in the county Geological
Surrey Of Iomn. ....