xt77h41jhj01 https://nyx.uky.edu/dips/xt77h41jhj01/data/mets.xml Kentucky Geological Survey. 1882  books b97-20-37304097 English Stereotyped for the survey by Major, Johnston & Barrett, Yeoman Press, : Frankfort, Ky. : This digital resource may be freely searched and displayed.  Permission must be received for subsequent distribution in print or electronically.  Physical rights are retained by the owning repository.  Copyright is retained in accordance with U. S. copyright laws.  For information about permissions to reproduce or publish, contact the Special Collections Research Center. Geology Kentucky Washington County.Linney, W. M. (William M.) Report on the geology of Washington County  / by W.M. Linney. text Report on the geology of Washington County  / by W.M. Linney. 1882 2002 true xt77h41jhj01 section xt77h41jhj01 












GEOLOGICAL SURVEY OF KENTUCKY.



JOHN



R. PROCTER, DIRECTOR.



                  REPORT


                    ON THm



GEOLOGY OF WASHINGTON COUNTY.



BY W. M. LINNEY.



STEREOTYPED FOR THE SURVEY BY MAJOR, JOHNSTON & BARRETT, YEOMAN PRESS, PRANKFORT, KY.

 This page in the original text is blank.

 















            INTRODUCTORY LETTER.



HON. JOHN R. PROCTER,
              Director of the Kentucky Geological Survey:
  DEAR SIR: I herewith submit my report on the Geology
and other natural features of Washington county, accom-
panied by map and section.
                            Yours, very truly,
                                    W. M. LINNEY.
  HARRODSBURG, Ky., November, 1882.

 This page in the original text is blank.

 








GEOLOGY OF WASHINGTON COUNTY.



                    TOPOGRAPHY, &C., &C.
  Washington was the first county organized after Kentucky
was admitted into the Union. It was originally a part of
Nelson, and at its formation, and for a number of years after-
ward, it included the present county of Marion. It now con-
tains about one hundred and seventy-four thousand 'seven
hundred and fifteen acres of land, and a population of four-
teen thousand four hundred and nineteen, according to the
census of i88o, showing a healthy increase of one thousand
nine hundred and fifty-five in ten years. Its position is near
the center of the State, and it is bounded on the north by
Nelson and Anderson, east by Mercer and Boyle, south by
Marion, and west by Marion and Nelson. Springfield is the
county seat, with a population of six hundred and ten. A
number of villages and post-offices are conveniently distrib-
uted through the county.
  There are several colleges and academies located in the
county, and the people have taken more than ordinary inter-
est in the erection of good buildings, in which the popular
schools are taught. Perhaps there is no one county in the
State which has a larger proportion of arable lands, as almost
every acre can be made productive under a wise system of
agriculture. The different soils of the county suit well for
the production of cereals, grasses, hemp, and tobacco. A
part of the soils are as fine as are found in any portion of
the State, producing large and excellent crops; and none of
them are really poor, where well taken care of and properly

 


GEOLOGY OF WASHINGTON COUNTY.



treated. A system of injudicious treatment has unfortunately
been given some tracts of land by which they have become
much less productive than their condition should be; yet they
afre of such character that their reclamation is comparatively
easy.
  The drainage of the county is perfect, there being no
swampy or wet lands within its boundary. Chaplin, Glens,
Little Beech, Cartwright, and Hardin creeks are the principal
waters; but into these and their tributaries enter a great
number of small branches, which carry off the excess of water
from every section. Without any exception, all the drainage
is into the Beech Fork of Salt river, which flows along the
western margin of the county. Properly speaking, the sur-
face is a plane, tilted a little from the southeast corner, where
it is highest, towards the northwest and west, where it is
lowest. The whole rocky structure has this inclination, and
the surface conforms in general to the slope of the rocks.
This slope has given rise, in time, to the original direction
of the streams, and they have continued since in their old
channels. As a result, their channels have cut deep into
their rocky floors, and given nearly the whole surface what is
usually termed a hilly character. One may stand on the high-
est ground in the southeast corner, or may go a few miles
into Boyle county, and ascend one of the knobs, and have a
fair view, which includes nearly the whole of Washington
county. The sight is a beautiful one of alternate rolling hills
and shaded valleys, extending as far as the eye can reach.
  Part of the southern and central sections is comparatively
level, or gently rolling; but over the remainder the water-
sheds are but narrow ridges, having drains leading off on
both sides, with inclinations of ten to forty degrees. These
are cultivated well, with seemingly but little extraordinary
labor. Along some of the streams, whose beds have been
widened out by erosion, there are small bottoms which are
very much valued for their productiveness.
  Washington has no railroad within its limits; yet it is
probable that one will be built in a short time from east to



6

 


GEOLOGY OF WASHINGTON COUNTY.



west through the entire county. Formerly, a good deal of
shipping was done on flat-boats down the Beech Fork; but
that enterprise ceased years ago. Turnpikes have been, and
are being, constructed in every part of the county, giving
facilities to the citizens to haul their goods and their produce,
and to drive their stock to shipping points, of which there are
quite a number at convenient distances in the surrounding
counties. Turnpikes are built cheaply, as they usually follow
the crest of the ridges or the valleys of the creeks, where
but little cutting and grading are required. The material for
macadamizing them is always close to hand, either in the
limestones of the hills or the gravel of the creek beds. The
pride and the liberality of the people in thus securing good
roads are commendable, and speaks well for their industry,
intelligence, and appreciation of their lands and surroundings.

                       GEOLOGY.
  A carefully connected section of all the rock series exposed
above the low water drainage in Washington county gives an
aggregate of seven hundred and sixty feet. At the top there
are seventy feet of the Niagara Period of the Upper Silurian,
and the rest is included in the Trenton Period of the Lower
Silurian. Fifteen feet of those are at the top of the Trenton
Group, and the other six hundred and seventy-five feet are
the equivalents of the Utica and Hudson River Groups,
here included for the present in the Hudson River Group
alone. The Hudson River Group is, for convenience, divided
into three series of beds.
  The namnes of the minor divisions used in this report were
given to series of rocks first intelligently studied in the State
of New York, and are names of localities where they were
best exposed for a careful investigation of their phases. To
retain the same names for the same group of strata exhibited
in each State is a great convenience; and this fact has led to
the adoption of the specific names given in New York geo-
logical reports by all the other States, so far as their stratified



7

 


GEOLOGY OF WASHINGTON COUNTY.



beds could be made to correlate with those in New York.
We have here tabulated them as we find them in Washington
county.
                                                        Feet.
NIAGARA PEROD......... .................... .       70
TTrrOm PERIOD -
    Hudson Mier Group. .675
    Trenton Group .15

    Total.                                           . , 7


                  TRENTON PERIOD.
  Trenton    Group.-The rocks in Washington county
belonging to the Trenton Group are not more than fifteen
feet in thickness, and this only at the Mercer county line,
where Chaplin enters Washington from the former county.
They are here seen rising that number of feet above low
water. Their dip being greater to the northwest than the
fall in the river, they sink below the latter in two or three
miles, and do not reappear again.
  The rocks of this group are very important ones in other
counties not far removed from this; but in Washington their
presence is of more scientific than economic interest. Here
there are no soils derived from them, nor have they in any
way shaped the topography of the county, or given character
to timbers or other plant growth. Their thickness is conm-
prised in a few layers of light and dove-colored limestones,
which lie at the top of the Trenton in several near countLies,
and which have received the name of " Upper Birdseyc" from
its close resemblance to the birdseye limestone below, which
is characterized by eye-like spots on its worn surface. Some
of these layers make excellent building stones, and also burn
into a fine quality of lime; but in this locality they showv
only on sides of steep hills, and it is not probable that they
will ever be quarried for those uses, for other rocks abound
in the vicinity which answer well those purposes, and are more
easy of access.



8

 

GEOLOGY OF WASHINGTON COUNTY.



9



  Hudson River Group.-This group of rocks is of
great extent in the United States, being at the surface in a
number of States, both in the east and west; and in all the
regions where it is shown it gives character unequaled to soils
that are immediately derived from the rocks in place.
  These rocks, which had their origin on the floor of a
very ancient ocean, are made up of the shells and corals of
that period, mixed with some clay and sand distributed by
the currents. These rocks, now hundreds of miles from the
ocean, and hundreds of feet above it, are year by year crumb-
ling into fragments, and dissolving into soil. Thus the remains
of the old life, millions of years ago, give to-day fertility and
character to the best soils of the country. As untold ages
have been required to give us these soils, it would seem that,
as a people, we should make every effort to retain them at
their best, not only as a source of prosperity to ourselves, but
as a heritage to those who shall come after us. The divisions
of this six hundred and seventy-five feet of rocks are here
natural ones, yet conform closely to the divisions made in
other States.

  Lower Hudson River Beds.-The lower two bun-
dred feet of the Hudson River Beds hold the position among
the rocks of this county, in part, which the Utica shales do in
the New York system. Their lithological characters are not
entirely the same, neither are the species of fossils which
are found in them so closely related as appears in the other
divisions; yet there is sufficient parallelism in their position,
in their character, and in their fossils to demonstrate that they
are the equivalents of each other, having been deposited at
or near the same time, the conditions alone being somewhat
different.
  The lowest layer is about one foot in thickness, and is semi-
crystallized, contains usually some rounded limestone pebbles,
some iron, and rolled fragments of shells and corals, evidences
of some disturbance which occurred at this time. The pebbles,
in their mechanical arrangements and the oxidation of the iron,

 

GEOLOGY OF WASHINGTON COUNTY.



cause this rock to disrupt very easily, so that it is not often
seen in place, but its fragments strew the surface in some
localities.
  Succeeding this is a number of layers made up almost
exclusively of fragments of one species of coral, showing
generally as round branches one third to one half an inch
in diameter, but often presenting a form like sections of a
small scroll. This form is common in other horizons, but not
to the extent shown here. It has received the name of C/ae-
tetes fibrosus. The layers are tolerably heavy where shown in
a fresh cut, but usually wear thin on exposures, and in many
places crumble to pieces, leaving the corals in great numbers
on the surface. Those layers are usually unfitted from this
character for fences or foundations, and when so used are often
destroyed in a few years. There are usually intercalated in
those coral beds several layers of crinoidal limestones, which
wear very well in any exposure, but are not very regularly
bedded.
  Upon these are situated some one hundred feet of thin
limestones, between every layer of which there is more or
less shale, a soft, earthy rock, erroneously called soapstone,
which goes to clay rapidly on exposure. This shale is several
times the thickness of the limestones, which are too thin and
irregularly broken for building purposes. The shales, how-
ever, waste so readily, and are so rich in the elements of
plant-food, that the soils are restored rapidly where badly
worn.
  Above the thin limestones and shales there are about eighty
feet of heavier limestones, among which are some that are
well suited for the builder and for lime-making. The propor-
tion of shales is very much less, and the stones are harder in
their character. Some of them are not evenly bedded, and
some have small masses of hard clay included in them, which
disfigure them for nice work. A reddish tint comes to many
of them on exposure. There are among these heavy layers
two and sometimes three layers which have their upper sur-
faces marked with great corrugations. These are seen in



10

 


GEOLOGY OF WASHINGTON COUNTY.



many places in the beds of the creeks; and when the roads
run over them, as they often do, they are very rough. These
are the hardest, toughest layers of rock in the whole series.
It is a curious problem how they should have been left in such
shape in the several layers, and so much alike in their appear-
ance, not only in Washington, but in a number of other coun-
ties. They are also seen as far north as the State of Ohio,
occupying the same horizon, and have been described in the
Ohio reports as - wave marks. "
  All these shales and limestones are internally blue, but
change very much to other colors when exposed to the air
for any length of time. They contain some little iron oxide,
and the alteration of that mineral, when exposed to the atmos-
phere, is probably the reason of the change of color. All.of
them contain fossils of many different kinds. Many of these
are well preserved, and can be gathered in great numbers at
many places.
  These two hundred feet of rocks and clay shales are
exposed in part over about one half of Washington; and
over the northern third they are alone to be seen, except
where the series next to be described has been left in small
patches on the highest hills. It is generally easy to determine
the part of the county composed of this series at a glance.
The disintegration of the shales, and their removal by rain,
are rapid. Consequently, when the shales decomposed into
soil by the action of the elements are removed by ploughing,
and by the washing from heavy rains, the limestones are
broken down and cover the ground. This is the case to such
an extent that one may sometimes walk over a whole field on
the blocks of stone alone. Had these been removed year by
year, and placed in fences, or used in building walls across the
deep hollows to catch the washing soils, farms would only
have been improved. Often these rocks were piled up in the
fields, or the land, where heavily cumbered with them, turned
out to wash still deeper, and to become sterile, except to.
worthless weeds or stunted shrubs.



I I

 

GEOLOGY OF WASHINGTON COUNTY.



  Those are good soils on the lower Hudson beds. The very
nature of the rocks, with the intercalated shales, produce a
steep, hilly surface, so that the slopes near the drainage lines
have everywhere inclinations of from ten to forty degrees.
With care these soils can be kept in good condition, and will
always give a good return to the farmer who knows how to
use them. Wet seasons are the most favorable ones for these
lands, as the compactness of the rocks and shales does not
make them good water-bearers; they do not hold water during
times of much dryness, to be diffused-through the earth, and
to afford by evaporation moisture enough for crops. Springs
are, as a general rule, not very plentiful in this part of the
county, and the water from them is generally charged with
more or less clayey matter; but cisterns are easily made, and
their water is very good.
  These soils were covered originally with a wonderful growth
of forest trees, of which the white oak of the best quality ex-
celled all the other timbers in numbers and worth. The axe
has sadly destroyed the forests long since.
  There are some remaining tracts where are some good tim-
ber trees, but the mills are fast culling the best for destruction.
On many of the farms the forests are about gone, and fire-
wood has become scarce. The future supply of lumber for
fencing and other purposes is a question which is becoming
important.
  Of late years quite a demand has been made upon the
white oak as material for whisky barrels; and large tracts of
land have been swept of their timber to supply this demand.
Fine orchards of sugar-maple were formerly utilized for sugar
making, but these have almost all been destroyed, and that
industry is known no more. Some lands have been turned
out to grow up into thickets; but without care they promise
little for the future. The white oak, under favorable condi-
tions, grows again; but with it comes every kind of trees
formerly indigenous to the soils, the poorer kinds ever in
excess (from the multiplication, preservation, and distribution
of their seed).



I 2

 

               GEOLOGY OF WASHINGTON COUNTY.                  13

  Very little quarrying has been done in these rocks. For
local uses the stones are generally taken from the beds of the
creeks, or gathered from the hill-sides. The building of found-
ations and chimneys, the burning of lime, and road-making,
are the local uses to which they are applied.

  Middle Beds Hudson River Group.-This division
of the rocks in the county is a natural one, as it gives a
different class of soils, and a peculiar distribution of timber.
The one hundred and fifty feet of rocks which comprise these
beds are made up of sandstones and sandy shales, with the
intercalation of several layers of impure limestones.
  The following section, made on the Little Beech Fork, gives
an idea of the component elements of these beds. (They were
named by Dr. Owen, in the old Geological Reports, the Sili-
cious Mudstone, a name which well represents their character):



Feet. Inches.                                        Feet. Inches.



159 ..    To soils derived from these shales.   ..... .   10  .
149...    Soft decomposing shale..... .. .. . .. ..    20  .
129       Tough smooth sandstone..............          2. ..2  .
127 .     Soft shales.       ........ .18 .
109       Heavy concretionary layer of sandstone, plated with a
             grey fossil limestone..    .   ..    .        2  .
 107 .. .. Shales... . . .. . .. .. . .. .. . .. ..     3  .
 104     1 Layer of limestone, packed with shells..... . ...          8
 103     5 Shales... .                                  4       4
 99     1  Layer of limestone, with fossils.4
 98     9  Shales.... .. .. . .. .. . .. .. . .. ..   19 . .  .
 79     9  Limestone, blueish-grey, semi-crystallized. .               8
 79     1  Shales... .. . .. .. . .. .. . .. ...
 74     1  Limestone.... .. . .. .. . .. .. . .. .. . . .  3
 73    10  Shales...... . .. . .. .. .. . .. .. . ..    4    8
 69     2  Limestone.... . .. .. . .. .. .                      3
 68    11 Shales.   . .. .. . .. .. . .. .. . .        8       6
 60     5  Limestone.... .. . .. .. . .. .. . .. .. . . .    3
 60     2  Shales... . .. .. . .. .. .. . .. .         5       2
 55     5  Limestone.          ..... .. .. . .. . .. .     5
 55 .. . . Shales.... .. .. . .. .. . .. .. . .        4 . .
 51 .. . . Limestone.... .. . .. .. . .. .. . .                6
 50     6  Shales... . .. .. . .. .. . .. .. . .. .   10  .
 40     6  Limestone.... .. . .. .. . .. .. . .. . .. . . 6
 40    .   Thin sandstones and shales........... 10 . .
 30 .... Top of lower beds.   .. .. . .. ..       .. . . ..  .
 10 .. .. Great wave marks.....  .. ....
            Bed of creek...........    ...

  All of these shales, limestones, and    sandstones are    blue
when opened    to some  depth, but it is rare to see them    ex-

 

GEOLOGY OF WVASHINGTON COUNTY.



posed in any way. When usually seen they are, except the
limestones, a dirty yellow. They are quite soft when first
exposed, but some of the heavy layers become quite tough
on exposure. They all decompose rapidly, and give great
depth to the soil. The sandstones and shales contain some
lime in their natural state; yet this is largely leached out on
exposed sections. The sand is rarely in a condition which
shows any grit, though this is sometimes the case. They are
rather porous, and when dry are much lighter in weight than
usual among such rocks. They are rarely used for building
purposes in this county, though they are sometimes seen
scattered here and there in stone fences.
  The rapid and deep decomposition of this class of rocks,
aided by their chemical character, gives a soil which is highly
valued in favorable situations. It is very easily worked where
it lies well, Contains much more moisture than the lower beds,
and, from this latter faict, in dry seasons the crops are always
better. It is much esteemed as corn land, for which crop it is
often cultivated many years in successiol. It is disposed to
wash on steep slopes, but this is hardly noticed by the mass
of farmers, as the next turning of the ploulgh leaves it in as
good a condition as before. This is usually the case; yet
there are exceptions where in one part of the mass the shales
are harder, and sometimes give sterile places unless great
care is taken to keep them covered with plants to prevent
the crumbling and rapid wear.
  On, the ridges, wells sunk into the soils give a very good,
cool, potable water, and of ample quantity.  The springs
which flow from it are few and scant, and the water is often
charged with earthy particles, which, I should think, from my
observations, do not add to its healthfulness.
  The drainage lines cut very deep and rapidly into these
soft rocks; so much so, that the heads of the hollows' usually
show inclinations of thirty to forty degrees; and this is true
of their lower lines, except where modified by the rocks above
or below.



14

 

GEOLOGY OF WASHINGTON COUNTY.



  All the roads follow the winding of the water-sheds, unless
where the lower beds give better conditions in the creek bot-
toms. Where there have been no turnpikes built the roads
are very bad through the winter, but very fair in dry weather.
Good turnpikes already constructed, and others to be com-
pleted, have, to a large extent, made it much more convenient
for traveling, and have enhanced the value of the lands.
  Originally, beech was the great prevailing timber over all
those beds; and even to-day, where the timber has been so
largely destroyed, this tree in its growth and distribution
marks the outcrop of the middle beds. WVith this species
was yellow poplar in considerable quantities, and of the finest
proportion, not Infrequently measuring eight or nine feet in
diameter, those of six and seven feet being quite common.
Fine black walnuts and white oaks were sometimes seen, and
quite a number of species were scattered here and there
among them.   The species named, however, grow in the
greatest profusion, and of remarkable quality.
  Where young trees have been allowed to grow over a few
lands which have been heretofore cleared, there seems to be
no settled order in their growth, this depending entirely upon
the distribution of the seed. Dogwood, red-bud, sugar-maple,
poplar, beech, white oak, red oak, black walnut, swamp white
oak, black gum, &c., may be noted. Dogwood and red-bud
are the great pests of these forests, coming in as undergrowth
in the old woods, and growing in thickets, often to the exclu-
sion of other species in the new. They are often so thick
that it is almost impossible to get through them. Notes of
this kind must be general in relation to the whole series;
there are exceptions to these statements, but they are of a
local character, and it is impossible to specify them over many
miles of territory.
  Some little shot iron ore is distributed in one or two hori.
zons in this division, and in places it is sufficient to show
in the roads and some fields as little patches of gravel. lThe
seams and surfaces of some of the layers are often discolored in
places by oxide of manganese, which appears as black blotches.



15

 

GEOLOGY OF WASHINGTON COUNTY.



The concretionary layers in these beds are singular, and their
origin is very obscure. A section of them shows as if they
were made by separate layers of sand and mud that were put
on one after another as envelopes around a central nucleus;
but it is impossible to see how this could have been done.
They split open into bowl-shaped masses, which renders them
unfit for any purpose. Some of these concretions are five or
six feet in length. This whole stratum is so much like the
Lorraine or Pulaski shales of the New York reports in its
bowl-shaped concretions, its sandy shales, and its disposition
to erode down so deeply and with such steep declivities, that
there can be no hesitation in referring it to the same equiva-
lence in time and condition.
  The shales and sandstones are bare of fossils, except as
moulds or casts. The lime of the structure is gone, but the
impressions 'of shells, corals, and trilobites remain to show
that they were deposited when abundant life existed in the
seas where they were laid down. Seaweeds of several kinds
grew in profusion during portions of that time, as they have
left their impress upon the surfaces, and in the interior of the
rocks. The limestones, however, are full of shells and corals;
but in such condition that it is nearly impossible to get good
specimens; besides, the speciA are few, and found in better
condition in the rocks above. The country around Mackville,
Willisburg, Thompsonville, and Beechland is based upon this
series. These rocks give quite a large area of soils in the
blue limestone region of the State, and will be treated of in
connection with the other groups in the reports on other
counties. The colored map will show their distribution over
the county, and the profile section the relation and position
they bear to the other divisions.

  Upper Hudson River Beds.-The upper beds of the
Hudson River Group in the county aggregate a thickness of
three hundred and twenty-five feet, and are composed of lime-
stones, shales, and impure sandstones. TFhe following general
section gives their average character:

 

GEOLOGY OF WASHINGTON COUNTY.



                                                           Feet.
Upper Silurian beds (on top) . . . . ...............
Coral bed..... .. .. .. .. .. .. . .. .. .. .. .. .. .. . . 16
Limestones.     . .. .. . .. .. .. .. .. .  ......... .   . 12
Sandstones, shales, and thin limestones . .................. . 75
Limestones and shales..... ... . .. .. ............... . 47
Earthy silicious limestones ................ ......... .    25
Heavy and thin limestones and a few shales........... .. .. .. .  .  35
Limestones and shales . . . ...................... . .    . 50
Thin limestones, with some shale..... .. .. ...... .. .. .. .   . 65
Middle Hudson River beds (at the bottom).    .  

                                                           325
  The lowest one hundred and fifty feet of these beds, if we
except a few layers in the upper part, are thin-bedded, " shelly"
limestones, with some intercalated beds of shales. They dis-
integrate well in natural exposures, and form by their decom-
position the best soils in the county. The layers are very
full of a great number of species of shells, corals, and other
organic remains. Whole layers are nothing but compacted
valves of shells and branches of corals, with a little earthy
matter to hold them together, which, dissolving, liberates the
specimens by thousands; these in their turn are dissolved,
and form the best of soils. One of these shells, known as
the Orthis lynx among collectors, is a very common form,
existing in such vast numbers that it has given a name to part
of this section of rocks, " the Lynx bed." This set of rocks is
quite uniform in its soil-making character, not only in the part
of Washington where it shows itself, but in quite a number of
other counties in the State. Blue-grass grows on them well,
and it seems to be the particular soil suited for the growth of
the White Burley tobacco.
  The most level farms in the county lie on these rocks, and
their general character everywhere is to wear into gentler
slopes than either of the beds which have been considered.
One coming off from the lower or middle beds of the Hudson
River rocks on to these, sees in a moment the change into a
more level country. The changes seen in the forests are no
less noticeable, for instead of forests of nearly all white oak
or beech, he will observe white and blue ash, hickory, wild
    GEOLOG. suRP-2



17

 

GEOLOGY OF WASHINGTON COUNTY.



cherry, yellow chestnut oak, swamp white oak, and a distri-
bution of other trees not observable on the other rocks.
  The next seventy-two feet contain much more earthy mat-
ter, and give quite a distinct soil. Tlhey produce a tolerably
heavy clay soil, with some amount of sicilious material. This
soil is highly valued, as wheat lands especially. It does not
grass so well as the other, and it requires more care in keep-
ing it from washing. White oak grows well on it, and the
soils have the local name of "\VWhite Oak Lands."  Several
layers of very good stone are contained in these where it is
not injured by small masses of silicious matter in the form of
"flint."  This division remains only in patches in the county,
and gives but comparatively small areas of soil.
  The remainder of the division is made up of a number of
layers of purer limestone, some shales, and a number of feet
of a peculiar rock, which has been termed the Cumberland
Sandstone in the Kentucky Reports. Several layers of these
limestones are very good for the common building purposes of
the county, and a few of them are well suited for the construc-
tion of finer houses, as they are remarkably even-bedded,
quarry well into dimension blocks, and wear as well in ex-
posed conditions as any building stones in the county. The
shales are like the other masses of their kind, composed of
clay and a little sand, and go to soils quickly when exposed.
  The Cumberland Sandstone is a mixture of clay and silica,
is heavy bedded, looks well in a quarry, where it has a blueish-
green tint, wears on exposure into a yellowish-green, a fresh
fracture often showing a discoloration of green or yellow. It
affords a tolerable soil, but it is a treacherous rock, for appear
however well it may, when freshly quarried and put up, it
soon breaks into fragments, and becomes worthless. This is
seen only in the northwestern part of the county, and its
area is quite limited.
  Above the last is locally seen from two to sixteen feet of a
bed that contains a vast number of corals, which resemble
honey-comb in their structure. These are in size from an
inch to two feet or more in diameter, and they literally cum-

 

GEOLOGY OF WASHINGTON COUNTY.



ber the ground in many places where the beds have become
exposed to denuding agencies.  Quite a number of other
fossils are associated with these, all of which will be noticed
in another report.

                    UPPER SILURIAN.
  Niagara Period.-As stated before, there are seventy
feet of rocks which lie at the summit or the section in Wash-
ington county, belonging to the Niagara Period. They are
seen only on the higher hills lying between- Hardin and Cart-
wright creeks, being thicker towards the Nelson county line,
beyond which they increase in magnitude until they form the
only series over a large part of that county.
  The following section, exhibited at the top of the hill south
of Fredericktown, gives an idea of the character of the Niag-
ara here. It is overlaid with a few feet of red clay derived
from the waste of the Corniferous limestone: