90 
THE CULTIVATOR 
$0ti«s erf Publications. 
DR. DANA’S MUCK MANUAL. 
In our brief notice of this work last month, we inti¬ 
mated our intention of again recurring to it, for the pur¬ 
pose of giving our readers a more full account of the 
principles advanced, and the manner in which they were 
supported, than could he done at that time. We do this 
the more willingly, both from the intrinsic value and im¬ 
portance of the Manual itself, and because it is the first 
contribution, which can properly be named as such, made 
by American philosophers to the cause of agricultural 
science. Circumstances have demanded that in many re¬ 
spects the processes of cultivation should be different in 
this country from those pursued in Europe. The cli¬ 
mate, the crops, the seasons, have contributed to give a 
distinctive character to American agriculture, and this 
difference is destined to become still more marked; but 
the principles which govern the germination of the seed, 
which regulate the nutrition and growth of the plant, 
which control the maturity and perfection, are and must 
be the same every where; and hence the various ques¬ 
tions which come under the name of scientific agricul¬ 
ture, have not received the attention here, they have in 
the old world. Admitting that the principles and laws 
of vegetable nutrition and growth were as well estab¬ 
lished and defined, as they are uncertain and obscure, the 
application of these principles would be a legitimate ob¬ 
ject of investigation; but while all inquirers can as yet 
be considered only on the threshold of the temple of na¬ 
ture, the field open to the competent observer both here 
and there, must be considered abundantly ample. We 
trust the success of this attempt, will induce Dr. D. to 
continue his explorations. 
Tne method pursued by Dr. Dana in the Manual, is 
very direct and perspicuous. His leading object appears 
to be, to convince farmers that in “ Muck,” that is in 
decayed vegetable matter, they have all the elements of 
fertility, and that there is no soil which with proper care 
and cultivation cannot be made productive. The work 
is divided into sections, which contributes greatly to fa¬ 
cility of reference, and prevention of repetition in the 
facts or arguments. 
Dr. Dana first establishes some general principles in 
regard to the action of soils and salts in producing vege¬ 
tation. This has led him to consider their structure geo¬ 
logically as well as chemically; and in our remarks We 
propose to follow him in his investigations, allowing 
him to speak for himself as far as possible. Dr. Dana 
remarks—“ Referring rocks to their origin, they are di¬ 
visible into two great classes. 1st, those formed by fire. 
2d, those formed by water. This division relates both 
to their origin and their distribution. In their origin, 
all rocks are truly igneous or by fire. In their distribu¬ 
tion they are aqueous or by water. This is the only di¬ 
vision necessary to the farmer. It is tiie division taught 
and demanded by Agricultural Geology.” 
From this view of the origin of rock, and the conse¬ 
quent general sameness in the chemical composition, he 
derives his first principle in Agricultural Chemistry, 
“ ONE EOCK AND CONSEQUENTLY ONE SOIL.” As a ne- 
cessary consequence of this principle, in his further in¬ 
quiry how rocks and soil affect vegetation, he lays down 
his second principle —“that bucks do not affect 
THE VEGETATION WHICH COVERS THEM.” 
We apprehend that this principle; understood in its 
broadest sense, and without restriction, would be erro¬ 
neous. Rocks do certainly exert a powerful influence 
on the soil that covers them in many cases, but this is 
owing to their physical condition, anil not to their che¬ 
mical constitution, in which sense Dr. Dana would in¬ 
tend to be understood. Temperature is the great agent 
which affects the vegetation of any strata or region, ac¬ 
cording to Dr. Dana, and this is depending on the physi¬ 
cal composition, rather than the chemical constitution 
of the rock. In this view of the subject, there will be 
little room for dissent to this principle. Take, for in¬ 
stance, a north and south section of western New-York. 
This would pass over strata of sandstone, lime rocks, 
gypseous shales, clay shales, &c. in repeated alternations, 
and the soils and the crops grown on them, are as well 
marked as the strata themselves. Those on the limestone 
strata are the most productive as a general rule, and these 
are also the warmest and driest; two qualities owing to 
the rock below,which, allowing water to pass off freely, 
give as a necessary consequence a higher temperature 
to the soil than belongs to that on the more retentive 
portions of the district. If soils were always formed of 
the rOcks immediately below them, there would be more 
room for disputing the disposition; but this every farmer 
knows is never the case, and consequently the chance 
for the chemical constitution of rocks affecting vegetation 
above them is much lessened. 
To show that it is temperature that governs the distri¬ 
bution of plants, and not the soil. Dr. Dana gives some 
interesting tables respecting the northern limits of some 
of th'e cultivated grains, such as barley and wheat, thus 
proving that it is not the average temperature of the 
year, or of the winter, but the temperature of the time 
employed in the growth of the plant, or of the summer, 
that determines its “ habitat.” North latitude 70° is the 
highest northern limit of barley; and latitude 64° the 
highest northern limit of wheat. Barley grows the high¬ 
est of the cereal grains, and a little beyond the line of 
this grain, is the northern boundary of the potatoe.— 
“ This belt,” says Dr. D. “ is the zone between agricul¬ 
ture, and fishing and hunting; between races of men 
■iiMsisting on animal and on vegetable diet, and those 
whose chief food is animal.” It is somewhat remarka¬ 
ble that in ascending mountains, the grains cease to grow 
at heights which correspond to the latitude marking the 
isotheral line, or their northern limit. Thus on the 
Swiss Alps the grains cease at the following heights: 
“ Wheat at 3,400 feet corresponding to lat.. 64“ 
Oats at 3,600 “ “ “ . 050 
Rye at 4,600 “ “ “ .67° 
Barley at 4,800 “ “ “ 70 °” 
From these facts, and the singular uniformity or iden¬ 
tity in the chemical composition of the soil, Dr. Dana 
adduces his third principle, viz: “rocks have not 
formed the soil which covers them.” The evi¬ 
dence of this is so ample, and so open to every observer, 
that we shall pass it without further remark. 
Dr. Dana’s second chapter treats of the chemical con¬ 
stitution of rocks, and is one of the best expositions of 
this subject we have yet seen. ‘‘ Seven simple minerals 
compose all rocks, viz: quartz, mica, feldspar, hornblende, 
talc, serpentine, carbonate of lime. Other minerals are 
found in, but these seven compose all rocks termed geo¬ 
logical formations, and which form the crust of the 
globe.” Of the 55 elements which chemistry has de¬ 
tected, 14 are found in rocks. This includes the ele¬ 
ments of water, oygen and hydrogen. Without these only 
12 remain. Of the earthy and metallic, eight; of the 
volatile and combustible, four. These elements of all 
rocks may be divided into four pairs—the alkalies, pot¬ 
ash, soda; the alkaline earths, lime, magnesia; the earths, 
silex, alumnia; the metals, iron and manganese. We 
have not room to follow our author through the instruc¬ 
tive details of this chapter; but the man who wishes to 
become acquainted with the combinations which these 
elements assume, will do well to consult it carefully_ 
The following table will show the constitution of the 
simple minerals 
“Feldspar, - • • 
Mica,. 
Hornblende, 
Talc,. 
Serpentine, ■ 
Oxide of 
Mane a- 
Iron and 
Silex. 
Alumnia. Lime. 
Potash, nese. Manganese. 
66-75 
17-50 1-25 
12-00 
0-75 
50-82 
21-33 
9-86 
9-03 
-45-69 
12-IS 13-83 
18-79 
7-32 
58-02 
water. 33-02 
4-06 
43-07 
0-25 0-50 
12-75 40-37 
1 -11” 
Thus it appears that silex is the most abundant ingre¬ 
dient in rocks, and alumina is next. “The average of 
these elements in the most important rocks, is silica 
62.79, alumina is 25.15.” In the best constituted soils, 
the proportion will not be found to vary widely from 
what is here stated, a proof that soils have originated 
from the decomposition and mingling of the elements of 
rocks. 
The third chapter is devoted to a consideration of the 
properties and chemical action of the elements of the 
soil. Here the important part performed by silica in 
vegetation is clearly developed, and its various combina¬ 
tions with other substances pointed out. The manner in 
which soils are supplied with lime and potash by the 
decomposition of rocks is here shown. The composi¬ 
tion of granite, composed of two-fifths quartz, two-fifths 
feldspar, and one-fifth mica, according to Dr. D., is as 
follows: 
Silex,. 74-84 
Alumina, . 12-SO 
Potash,. 7.48 
Magnesia,. 0 • 99 
Lime, . o-37 
Oxide of Iron,. 1.93 
Oxide of Manganese,. 0-12 
To show that soils are not exhausted of their lime or 
alkali, Dr. Dana shows the quantity of each an acre of 
soil, made from the decomposition of such rock as the 
above would produce, taking the soil only six inches deep. 
“ The cubic foot of such soils weighs about 90 lbs., or at 
six inches deep, 45 lbs. The acre at this depth, con¬ 
tains 21,780 cubic feet, which will afford 3,626 lbs. of 
lime, and 73,311 lbs. of potash, or nearly a ton and a 
half of lime and 36 tons of potash.” The probability of 
the exhaustion of these substances may be inferred from 
the following estimate. The straw of a crop of wheat 
of 30 bushels per acre, will weigh about 5,000 lbs_ 
Burned, this will yield 220 lbs. of ashes, of which one- 
fifth is soluble in water, and consists of one-half of that 
dissolved, of potash. The part not soluble, contains 5.80 
per cent of lime. Thus an acre of wheat straw contains 
22 lbs. of potash, and 10 lbs. of lime. From these facts 
Dr. D. deduces his fourth principle, viz: that all soils 
CONTAIN ENOUGH OF LIME, ALKALI, AND OTHER INOR¬ 
GANIC ELEMENTS, FOR ANY CROP GROWN ON THEM. 
When it was stated in Prof. Hitchcock’s Geological Re¬ 
port, on the authority of Dr. D., that all soils contained 
phosphates and sulphate of lime, a principle of great 
importance to the farmer, it was received with doubt ami 
distrust by many, principally from the fact that many 
crops, wheat in particular, for the production of which 
lime is deemed essential, could not be grown on much 
of the soils of New England. The proofs, however, are 
abundant. The bones of animals, a great variety of 
vegetables, contain phosphates and sulphates. All our 
cereal grains contain them both in the grain and in the 
straw, and half the weight of bone is a phosphate. On 
these facts is based Dr. Dana's fifth principle, that all 
SOIL CONTAINS SULPHATE AND PHOSPATE OF LIME. 
Dr. Dana’s fourth chapter is on the “Organic constitu¬ 
ents of soil.” “Whenever plants die, their elements 
are again subject to the laws of affinity, and during the 
decay of vegetables, they return to the earth not only 
those substances which the plants had taken from the 
soil, but also those which have been elaborated by their 
living structure. The former are silicates and salts, or 
the inorganic elements; the latter are the organic parts 
of the soil.” The organic elements of plants “ are the 
product of substances once endowed with life;” and “ the 
great difference between the two divisions, is this, that 
while the inorganic are simple combinations of two ele¬ 
mentary substances, the organic are combinations of 
three or four elements, but never less than three.” From 
the fact that plants are always composed of several ele¬ 
ments, Dr. D. draws his sixth principle, that soil, 
CONSISTING CHIEFLY OF ONE SILICATE, OR SALT, IS AL¬ 
WAYS BARREN. 
Dr. Dana’s seventh principle in agricultural chemistry, 
is based on the fact, “ that one base may be substi¬ 
tuted FOR ANOTHER, in an isomorphous proportion,” 
or the law by which one element may be substituted for 
another, which produces a like form. For example the 
alumina in alum may be replaced by iron; the form will 
not be changed, but its chemical properties and relations 
will be totally destroyed. This fact of substitution is of 
the highest practical value, since where one element 
happens to be exhausted in a soil, the organic acid of 
the plant, will appropriate another, and thus be enabled 
to perfect all its functions. 
The great mass of organic matter in soils, is a well 
defined chemical compound, called by Dr. Dana geine, 
by Liebig and Berzelius humus, and by Braconnet, Bou- 
lay and others ulmin or ulmic acid; and consists of car¬ 
bon, hydrogen and oxygen. The product of decayed or¬ 
ganic matter; the name is of very little consequence to 
the farmer, so long as he remembers that without the 
presence of this substance in the soil, plants cannot grow 
and perfect their seed; that without geine or humus , crops 
are never raised. Dr. Dana well remarks, “ that geine 
is as essential to plants as food to animals; and so far as 
nourishment is derived from the soil, geine is the food 
of plants.” On this is based his eighth principle, “ that 
GEINE IN SOME FORM, IS ESSENTIAL TO AGRICULTURE.” 
So far as the value of geine is concerned, it matters 
nothing at all to the farmer, whether he believes with 
Liebig that plants derive their nourishment almost en¬ 
tirely from the air, or with Dana, Johnson, and others, 
that some portion of it is taken up by the root; since in 
the first case, the carbonic gas absorbed from the air is 
generated by the geine, and in the last, is furnished di¬ 
rectly to the roots of the plants from the decomposing 
geine of the soil. It is the changes which this substance 
undergoes, the various combinations it forms with the 
several alkalies and acids with which it comes in con¬ 
tact, which gives it its great importance in the estima¬ 
tion of the agricultural chemist and farmer. Vegetable 
mold is a mixture or compound of soluble geine, with 
earths and metals,mixed with soluble and insoluble geine. 
In rich mold there is usually a large portion of free or¬ 
ganic matter. With lime, alumina, iron, &c. geine, or 
geic acid, forms compounds called salts or geates. These 
salts are soluble in water, and are of the utmost conse¬ 
quence to the farmer. Into the chemical history of geine 
or humus, we cannot here enter. Those who take an 
interest in the matter, will find a good account of it in 
the appendix to chapter IV. It is sufficient to state that 
Dr. Dana prefers the term geine, to any of the others that 
have been given this substance. 
“ The elements of soil, are silicates, salts, and geine. 
The silicates as such have no tendency to re-act on each 
other. They are gradually decomposed by the action of 
the air. The great agent in this action is carbonic acid, 
which gradually combines with the alkaline base of the 
silicates, and the potash and soda are converted into so¬ 
luble salts, whilst the silex and alumina remain.” Dr. Da¬ 
na's exposition of the action of the class of salts is admi¬ 
rable, and shows how the effect of the carbonates upon 
soil is produced. From their action as explained, is 
drawn the ninth principle; carbonic acid, and 7 he 
CARBONATES, DECOMPOSE 7 HE EARTHY, ALKALINE AND 
METALLIC SILICATES OF THE SOIL. 
Dr. Dana gives an interesting account of what the 
French call action of presence, or caialysis. It is well 
known by chemists, that the mere presence of a body, 
influences the nature of a second body, so as wholly to 
change its properties. For example, starch is converted 
into sugar by oil of vitriol. The acid suffers no change. 
It acts by mere presence, and converts the starch into 
sugar. A distinguished German chemist maintains that 
all decomposition takes place in obedience to a third 
substance acting by its presence. So the vital principle 
of plants, let it be called life, electricity, galvanism, acts 
by its presence and gives power to enter into new com¬ 
binations. A living, growing plant, in soil, will in one 
year effect a greater amount of decomposition, than all 
atmospheric influences can in many years. 
To determine how salts or mineral manures*act, is 
one of the most important inquiries of the chemist or the 
farmer. It is not enough to say they are stimulants; that 
“ they are to plants what condiments are to the food of 
man.” “ Some general principle is demanded which 
w'ill enable the farmer to say what the action of a salt 
will be; and whether he may apply one or less than one 
per cent of it, without risking his crop.” This general 
principle, according to Dr. Dana, is found in the follow¬ 
ing, which is his tenth principle of agricultural chemis¬ 
try. THE BASE OF ALL SALTS, ACTS EVER THE SAME IN 
AGRICULTURE. PECULIARITY OF ACTION, DEPENDS ON 
THE ACID OF the salt. On this principle, the Dr. lays 
great stress, and we think deservedly. Lime for instance, 
which forms the base of a vast variety of salts, can never 
act otherways than as lime; but when united with phos¬ 
phoric acid, as in bones, or with sulphuric acid, as in 
plaster of Paris, very different results ensue from its ap 
plication to plants. Our readers are aware of the theory 
of Liebig in regard to the action of gypsum, which he 
supposes to arise solely from its absorption of the ammo 
nia of the air and water, by which soluble sulphate of 
ammonia is formed and appropriated by the plant. The 
