North Carolina. State Geologist.

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[Message and Report communicated to the House of Com-
mons. Transmitted to the Senate with a proposition to print
3000 copies. Ordered accordingly .

To the Honorable the General Assembly

of the State of North Carolina :

1 herewith transmit the Report of Prof. E. EMMONS,
who was appointed, under the Act of the last Session, to
make a Geological, Mineralogical, and Agricultural Survey
of the State.


Raleigh, November 22d ; 1852. j


To His Excellency, DAVID S. REID,

Governor of North Carolina :


1. Agreeably to the requirement of the Act of the
Legislature, passed the 24th January, 1851, authorising a
Geological Survey of the State, I herewith present the First
Annual Report.

In the discharge of this duty, I have deemed it advisable,
at this time, and at this stage of the work, to confine my com-
munication to two principal subjects : the Soils and Agri-
culture of the Lower Counties ; and the Coal Fields of Rock-
iugham. Stokes, Chatham, and Moore Counties : the two
former occupying the Northern, and the latter the Central,
portions of the State. I deem it, however, relevant to the
subjects before me, to introduce the statement of such
principles of Agriculture and Geology as may be required for
the better understanding of these departments ; or which are
suggested by, or flow immediately from, facts which I have

I hope this course will be approved of, as the subjects are
beginning to excite public attention, and are probably among
the most important matters to which the public attention has
been turned for many years.


many points which have been established, of
y^ars; thejtfe:arV /our of very great importance, namely :
That soils must contain a sufficiency of certain inorganic
dements ; that these elements are necessary to the life of the
plant that no seed can be perfected without them ; and-,
finally ', that they are essential to the life of the animal sub-
sisting on vegetable food. It follows, from these established
points, that some, at least, of the important products of life
are derived from the soil ; it being possible to trace them back
from the animal, through the plant, to the soil. From this, it
also follows, that the true method of determining the important
elements of a soil, is, to analyse the products of life as found
in the plant and animal. That \Uiich is constantly found in
those products, and which can be traced to no other source
than the soil, must, of necessity, be regarded as the essential
elements of the soil. We can arrive at no other conclusion .
and furthermore, by no other method can we reach a correct
conclusion. This method has been followed ; and it has
resulted in (he discovery that the following substances are the
essential ones which have been alluded to, namely : Phos-
phoric acid, Sulphur, Potash, Soda, Lime, Magnesia, Oxyde
of Iron, Silica, Nitrogen, Oxygen, Hydrogen, Carbon, Water,
Ammonia, Chlorine, and small quantities of Fluorine.

I might have left out of this list oxygen, hydrogen, nitro-
gen, carbon, and ammonia, inasmuch as there are, it is sup-
posed, other sources of supply than that of the soil. It is no!,
however, fully established that, in the arrangements of nature,
there is a full provision for this supply, when soils are subject-
ed to high culture, and are required to produce more than five
times the amount which they produce spontaneously. It is
undoubtedly true, that the vegetable kingdom can sustain
itself by the instrumentality of the common sources of supply ;
yet, when a species of this kingdom, as Corn, for example,
is required to yield its sixty bushels to the acre, we can see no
provision for this result in its wild and uncultivated state.

Hence, under culture, where the soil is thus heavily (axed to
meet the demands of civilized life, there it fails, in process of

time, to supply them, and means to supply them are called
for, and even required, in order to sustain the soil undei its
increased products. Those elements, then, which constitute
parts of the atmosphere, as carbonic acid and ammonia, which
are furnished in sufficient quantities to plants, growing spon-
taneously, are not supplied, as I have already hinted, when
soils are put under heavy culture 5 or, they may not be sup-
plied in sufficient quantities to meet the demands of a succes-
sion of crops.

3. As I shall have frequent occasion to refer to those
elements of soil, generally known as inorganic elements,
I propose, in this place, to speak of them ; and to state some
of their properties, uses, and the sources whence they are de-

1. PHOSPHORIC ACID. In its separate state, insulated
from other bodies, it is an exceeding sour substance. It is
solid, and resembles flakes of snow, when freshly prepared ;
but, in consequence of its avidity for water, it soon becomes,
in the atmosphere, a limpid fluid. Like other sour or acid
bodies, it readily combines with potash, soda, lime, and many
other bodies ; and forms, with them, new compounds, which
are called phosphates. Hence we have phosphate of lime,
which exists both as a natural substance in rocks, and in the
animal kingdom in bones ; and it is mainly in this form or
combination that it is known in the animal and vegetable
kingdom. Animal bodies all contain more or less of phos-
phate of lime, and probably it is among the most important.
The bones, however, contain more of it than other parts ; and,
in its absence, and when it is diminished in quantity, they are
soft and flexible, and unfitted to sustain the weight of the body.

The source of phosphate of lime is the mineral kingdom.
Probably all the rocks contain it, sometimes in large masses ;
but, usually, it seems to be diffused through them in fine
particles. When they decompose and disintegrate, it is, of
course, mixed with (he soil. It is more abundant in granite,
greenstone, trap dykes, and volcanic products, than in othe^
rocks. This fact seems to show thai igneous rocks, the pyro-

chrystalline, are the true sources of this important substance.
In New York, I discovered, in 1837, a vein of it subordinate
to a trap dyke, and in connexion also with the primary or the
pyrochrystalline limestone all of which may be classed toge-
ther as igneous products. This vein, in one place, was seven
feet wide ; and hence furnished a large amount of lime for
agricultural purposes. In the same section, I discovered the
same substance associated with the magnetic oxyde of iron, in
small clustered crystals, forming, in many places, more than
one-half of the mass.

In the trap dyke, this mineral phosphate is green, less hard
than feldspar ; and, in the iron bed, in reddish, six-sided prisms.
1 am careful to mention these facts for this important sub-
stance may exist in the pyrocrystalline rocks of North Oarolina ;
and, if in quantity, would be of great value to the agricultural
interests of the State. It should be sought for in rocks of
igneous origin ; and especially where the magnetic ores of
iron exist. In this state it occurs in the marl beds, at the bot-
tom of the shell marl ; though it is also diffused through the
beds, in masses of small size; ic is in dark rounded and some-
times spiral masses. In this form, it is known under the name
of coprolite. It is the excrement of marine animals, and coir
tains rather more than 50 per cent, of phosphate of lime ; or
about the same proportion as it exists in bone. These copro-
lites are very valuable, and 1 have indicated the place where
they abound the most. They seem to have been collected at
the bottom of the shell marl, and to have been subjected to
attrition by the waves of the sea. They are associated with
quartz pebbles, and generally are black or brown, and almost
as hard as quaitz. Coprolites are found also in the coal
stratas of Rockingharn, Stokes, Chatham, and Moore. They
have a similar origin to those of the marl beds but they
do not exist in sufficient abundance, as 1 have seen in either
formation, to warrant the expense of extracting them. Still
the facts are important, and should not be forgoaen. The
importance of this substance cannot be doubted, when it is
known that Indian corn, wheat, rye, oats, barley, all the

cereals, potatoes, and all the tubers and tap-rooted plants con-
tain it ; and especially the cereals. A soil destitute of it is
totally barren.

2. SULPHUR. It is a substance too well known to require
a description. It is not so well known, however, that it is an
important element in the vegetable and animal kingdoms. It
is found in the animal tissues. Peas and clover belong to a
family of plants in which it is always found. It is an element
of oil of vitriol, and hence one of the elements of gypsum. A
class of minerals called sulphurets also contain it.

3. POTASH. Equally well known is potash. It is a con-
stituent of granite, existing in the feldspar of the rock in the
proportion of 16 per cent. Owing to its presence, this mineral
is subject to decomposition , and then forms kaolin; a substance
employed in porcelain. Other minerals contain it. The
green sand, one of the varieties of marl in the Eastern Coun-
ties, owes its fertilizing properties to potash. It plays an im-
portant part, both in the organic and inorganic world. It is
instrumental in giving solubility to silex ; and hence prepares
this substance to be taken up into the tissues of plants. In com-
bination with potash, silex is taken up, and made a part of
the straw of wheat, rye, and oats, and imparts that strength
which is necessary to enable the plane to stand up. When
deficient in silex, wheat, rye, and other grains fall, and are
injured or destroyed.

Potash is an expensive fertilizer, ranking, in this respect,
with phosphate of lime. To this, more than any other ele-
ment, ashes owe their value as fertilizers. Argilaceous soils
contain it, in combination with silex ; but the combination is
insoluble, and requires the addition 01 lime to free it from a
portion of silica, in order to bring it into a soluble condition.

4. SODA. This alkali is more abundant than potash, and
beds of nitrate of soda exist in climates where no rain falls.
Its office, in plants and animals, is not very dissimilar to that
of potash. The great source of it is the sea, and beds of
rock salt.


5. LIME. Lime, in some form or combination, is found in
all parts of plants and animals. The bark of trees abounds
in it, where it serves to protect the wood from injury ; and the
testaceous covering of shell-fish, oysters, and clams, together
with the integuments of crabs, and the substance of corals. In
bones, it is in combination with phosphoric acid ; while, in
the bark of plants, it is probably in combination with organic
acids ; and, in the testaceous covering, it is combined with car-
bonic acid. It is more generally diffused in the mineral
world than either of the alkalies, or alkaline earths ; and still
it is one of those substances which is wanting in soils, and
that, too, when they exist in the vicinity of limestone rocks.

Lime also exists in the bones of man, in the proportion of
about twelve per cent. From its .universal diffusion in the
vegetable and animal kingdoms, it is evident it is one of the
important elements of the soil. Its presence in the soil,
however, is not so common as might be expected from its
great abundance m the mineral kingdom. We have no cal-
careous soils, even upon our limestone, though there may be
patches of a few yards in extent where lime is the principal
substance. Much uncertainty prevails in the use of lime. I
shall, however, reserve what I have to say, under this head,
until I have occasion to speak of the use of marls.

6. MAGNESIA. It is often maintained that magnesia is
hurtful to soils. When caustic, it does not become mild so
soon as lime ; and hence is liable to absorb the water which is
requiied ly plants. Yet the phosphate of magnesia is a con.
stant element of the wheat, rye, and corn, as well also as in
all vegetable food, [t exists in soil; is important to fertility :
but is less so than lime. Its source is in the magnesian rocks,
as they are termed, such as soapstone and steatite talcose slate.
It is far less soluble than lime. When barrenness appears
in connexion with serpentine, it is not because magnesia is
injurious, but because other earths are wanting or absent.
Magnesian limestones have rarely, if ever, injured vegetation
in this country, though prejudices exist abroad.

7. SILICA. In flint and rock crystals, we have examples
of this earth. It is harder than glass ; and, in the common
form in which it is found, is insoluble. It appears, in this
form, to he one of the most indifferent of all bodies. Yet it
is found in such combinations that it is freely taken up by the
roots of grasses, and plants of this family. It constitutes a
very large proportion of the earth's crust. In soils, it varies in
quantity. Its proper proportion is about 85 per cent, ; but
good soils often contain less, and two 01 three per cent. more.
The office which silex performs is to preserve a due amount
of the coarser matter : for, when a soil is composed of impal-
pable matter, it is comparatively barren ; and silex, from its
excessive hardness, resists the wear and action of the elements.
By being commingled with clay, it imparts porosity and loose-
ness ; permits the roots to ^penetrate deeply; while, at the
same time, air and moisture permeate through the mass as far
us roots can find their way. The use of silex is, therefore,
partly mechanical and partly physiological ; being necessary
m soils to preserve porosity, and particularly necessary to the
cereals to protect the straw and kernels, and give elasticity and
strength to the whole plant. So abundant is this substance,
however, that it is never necessary to add it to the soil, except
for mechanical use ; potash and lime are often added for the
purpose, of freeing it from its insoluble combinations, when
the grains are special objects of culture.

8. OXIDE OF IRON. Analyses of organic bodies, prove the
existence of iron in them ; and in those animals which have
red blood, it is satisfactorily demonstrated that it serves to main-
tain the heat of the body. In addition to this, its salutaiy ef-
fects upon the human system prove, also, that it performs

^ome other office besides. It is, then, an important element,
physiologically. In the soil, however, it is supposed to be
concerned in developing or forming ammonia. Iron, by it-
self, is rarely used as a fertilizer. The oxide, however, taken
from the smith's forge, intermixed witli refuse matter collect-
ing about a smith's shop, is often highly beneficial to fruit
trees ; and pear trees, especially, have derived essential benefit
by the application.


9. AMMONIA. It is known by everybody, under the name
of hartshorn. In this State, however, it is not applied to
plants, or to soils. It belongs both to the soil and atmosphere.
Nitrogen, an element of the atmosphere and ammonia, is an
essential constituent of the cereals, being one of the compo-
nents of gluten, or the pasty part of flour. It is supposed
that the salts of ammonia are the media, through whkh nitro-
gen gains access to the grain and there are results of experi-
ments which go to prove that, if it is wished to increase the
wheat crop, it requires the addition of substances which will
furnish ammonia that the fertilizers 1 have noticed in the
foregoing paragraphs are not sufficient, or are inefficient, in the
case of wheat, unless they are mingled with ammoniacal com-
pounds. Phosphate of lime will greatly increase the turnip
crop j yet, if applied to \vheat, when the soil is unexhausted,
with a view to increase the product, it fails, unless ammonia
is furnished also. Yet, on poor and exhausted lands, phos-
phate of lime is known to produce surprising effects. In fiesh
soils, plaster and charcoal readily absorb ammonia.

WATER. This element is the great solvent of the different
inorganic bodies upon which I have been speaking. Nothing
can act and become beneficial to vegetation, until it is dissolv-
ed in water. It is, therefore, the medium through which all
the essential substances find their way into animal and vege-
table tissues. The effect of much is injurious. Standing, as
it frequently does upon soils, it diminishes their temperature,
and maintains them in a state permanently too low to admit
of the cultivation of the valuable plants. Draining lands of
superfluous water is, in effect, raising their temperature several
degrees. Where there is too much water, another condition*
exists incompatible with that cultivation which the cereals re-
quire ; the soil is too compact, and it cannot be made po-
rous while in that condition . Draining, therefore, makes the
soil warm and loose ; conditions essential to the growth of
the most important productions.

Water is indispensable, and no seed can germinate without it.
Soils differ as to the force with which they retain or absorb it.


Silicious soils part with it readily, and absorb it slowly. Of
all substances which retain water, finely divided peaty matter
is the strongest ; it exceeds clay und marl. Next to peaty
marl, fine marl, containing some organic matter, ranks the

10. CARBONIC ACID. The atmosphere is regarded as the
source from which it is obtained by plants. In this combina-
tion, it is always produced, and it is generated in the soil.
Carbonic acid is a solvent. Water charged with k dissolves
rocks. The almost insoluble phosphate of lime is thus dis-
solved in water by its aid.

Leaves are supposed to absorb it from the atmosphere ; and
to obtain, in this way, the carbon required to build up their
structure. Still, the water in the soil holds it in solution ; and
it is, under those circumstances, furnished the. plant by its
roots. This seems to be the channel through which carbonic
acid may more naturally course through its tissues, when it is
assimilated. Carbonaceous, or peaty matters, also supply it.

11. CHLORINE. Common salt is a combination of soda
and this substance. The term chloride is applied to such
combinations. By itself it is a poison ; in combination with
soda, it is a fertilizer. Its true value, however, is not well
settled. Some esteem it highly ; others do not. On wheat
its effects are scarcely perceptible. It promotes the growth
and yield of plums, and it may be taken up in sufficient
quantity to give them a saline taste.

12. FLUORINE. li is found in combination with lime, con-
stituting the mineral called fluor spar. Although it is a rare
substance, yet it is found in the enamel of teeth, in bones, and
in milk. It is an associate of phosphate of lime. It is never
added to soils by itself ; but, as it accompanies phosphate of
lime. 1 believe, in all cases, it is applied when phosphate of
lime is used. *

* In the foregoing pages, I have used the word clement iu
a different sense from (hat in which it is employed in chemical
works. Real elements, or simple bodies, are never employed
as fertilizers. They must be compounded, before they are
received as elements.


The foregoing substances are detected in the ash of plantst
When plants, wood, coal, &c. dre burned, the ash tha
remains is called the inorganic part of the plant. If they
are burnt carefully, in a proper flame, we find that the
particles composing the inorganic part preserve a reticulated
structure, and often appears as woven. It seems, theiefore,
to be designed to perform the part of a skeleton to the plant,
and give it firmness and elasticity. Even the delicate petal of
a plant has its fine woven skeleton. Two things should be
observed of the inorganic part : plants differ among them-
selves in the quantity they contain ; and the parts of the same
plant differ also in this respect. These two facts lie at the foun-
dation of an improved and refined system of agriculture.
That improved system would consist in adapting the quantity
of the inorganic elements to the special wants of the plant.
In the present state of our knowledge, something can be done,
but it must be done imperfectly. Hundreds of acres under
cultivation can receive only rough and imperfect tillage. Spe-
cial agriculture, that which is conducted to meet the special
wants of the crop, must limit and confine the operations to
small plantations. This special agriculture is, inpait, observ-
ed, when the planter and farmer puts his wheat on soils best
adapted to wheat ; or when his Indian corn and potatoes are
cultivated on soil best adapted to them. But when the sys-
tem of artificial farming is undertaken, it is necessary that
more knowledge of the soil should be obtained than can be
procured by simple inspection. A full knowledge of the com-
position of soils is the first step towards veal improvement in
the right direction. To carry the improvement to perfec-
tion, -a full knowledge of the composition of plants is also
necessary But plants vary much in their relations to light,
and shade, heat and cold, to dry and wet soils. The condi-
tions of vegetation best adapted to plants, or to crops, must
receive study ; the reasons why they vary should be deter-
mined. All these points require a knowledge of the economy
of vegetation, or of its physiology. The range of knowledge
required for the practice of a special agriculture, or where spe-


cial adaptations are attempted, is by no means confined to a
small compass. This is not to be regarded as a discouraging
feature. To progress, however, requires the utmost patience,
and the great danger is, that discouragements will spring up at
the slow progress which is made, and a right road will be
abandoned, because it can be seen only for short distances ; the
end is yet hid in mist and doubt.

The organic part of a plant, is that which is consumed dur-
ing combustion : the products being volatile, are all dissipated.
It forms by far the greatest part of the vegetable. Its source is
regarded, by Liebig, as the atmosphere. Still, the soil no
doubt furnishes it, in the form of organic salts, which are
known under the names of crenic and apocrenic acids in combi-
nation with alkaline matters. These are derived from humus
originally, plants first changing in water into peat, which, in
itself, is scarcely soluble, but which becomes so, in part, by
the action of lime.

4. It has been stated that certain elements are essential to a
productive soil. Knowing before hand what those elements
are, it seems to be plain what course our enquiries should take
when directed to the improvement of any given soil. If a
crop is defective in quality, and falls short of its former yield, it
is evident thas there isa want of those elements which have Just
been described ; the course to be taken then, is to analyze the
soil, especially those patches where the failure in quantity is
the greatest. If it is found deficient, in some of those ele-
ments, we are put in a way to correct the evil. It is possible
that this report may fall into the hands of a few who may
wish to know the chemical composition of soil, really poor,
as well as those which are rich. I shall proceed to give the re-
sults of an analysis of several kinds of soil, in order to make
my readers better acquainted with their composition, that they
may be used for a comparison hereafter ; and as they are taken,
from well known plantations in different parts of the State,
the results may also be regarded with more interest than if se-
lected from books. The planter wants to know the reason of
the 'failure of his soil to produce its customary crops. But til-


lage must be taken into the account, as well as the season :
and, indeed, all those variations in seasons, time of planting,
favorable conditions of soil, &c. which are necessary to arrive
at a true conclusion. If the failures belong to successive sea-
sons, equally favorable to the crop, there can be no doubt
they arise from a deficiency of one or more of the inorganic
elements of I he soil. There may be a kind of a priori deter-
mination of the cause of failures by looking back for several
years, and calling to mind the kind of crops taken from it.
If they have been cereal, then it is highly probable that the

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Online LibraryNorth Carolina. State GeologistReport of Professor Emmons, on his geological survey of North Carolina [electronic resource] → online text (page 1 of 14)