VoL. IV. 
AUGUSTA, GA., JULY, 1840. 
No. 7 
A LETTER ADDRESSED TO THE AGRICULTURAL SO- 
CIETY OF JEFFERSON CO. GA.BY J H. HAMMOND. 
[ Concluded. ] 
But lo detail all the operations of lime ia the 
soil, in assisting to prepare food for plants out 
ot the vegetable and mineral substances which 
compose it. would require me to write a much 
longer letter than you would read with patience, 
i have touched on the most prominent only. 
The general consequences, however, which tol- 
low, and which are regarded as arising pecu- 
liarly from its application lo land, require to 
be glanced at. 
By opening stiff land, it renders it more per- 
meable to the air, and more subject to atmos- 
pheric influence, while its surplus water more 
readily escapes. Gtuick-lime, when saturated, 
holds more water than common clay, such as 
■ yours, but yields it more readily to heat, and is 
.therefore of great use in drying damp lands and 
rendering them warmer. But it does not give 
up its water so promptly as sand, and therefore 
re'nders that more retentive of moisture. In 
fact, marl containing 50 per cent, of carbonate 
of lime, and the residue chiefly fine sand, will 
absorb more water than the common clay uf 
your lands, and retain it as long. During the 
extreme drought last year, at one time, the plow 
turned up dry dirt ia a field of mine marled that 
year at 100 bushels per acre, and not yet suffi 
eiently mixed in the soil, while several days la- 
ter, without intervening rain in a soil equally 
sandy and having less vegetable matter, but 
marled four years ago wi.h *200 bushels per acre, 
earth quite moist was turned up at the same 
depth. You will reaiily perceive and appre- 
ciate the value ot marl in this respect. 
By rapidly neutralizing the noxious, and vi- 
vifying the good properties of the subsoil 
brought up in breaking land, lime enables the, 
farmer to deepen his soil more speedily and 
vjiihout risk. Mr. Ruffin’s experience conflrm- 
ingthe theory, is decisive on this point; mine, 
so far as it goes, is to the same effect. Lime 
undoubtedly hastens the maturity ot crops. 
Writers abioad state that it advances the n a 
fortnight. Before seeing these statements, my 
observation of my own crops had led me to the 
same conclusion. Two weeks gained to the 
cotton plant is equivalent to a degree ot latitude 
— a very material gain lo us. 
It is also stated on good authority that lime 
in land improves the quoAity ot every cultiva- 
ted crop— and that it has the effect of increas- 
ing the fruit in proportion to the weed. It is 
'well known, that while the straw, stalks, &c., 
of plants, contain more of the carbonates, the 
seeds contain more of the phosphates. It the 
application of carbonate of lime increases the 
fruit more than it does the stalk, its indirect in- 
fluence in producing phosphates is greater and 
more impoitani than has been generally suppo- 
sed, and its value is enhanced in a correspond- 
ing degree. It is said also to extirpate many 
noxious weeds. However this may be, I can 
testify that it gives great luxuriance to the 
growth of all the grasses with which our crop.s 
are infes'ed. This, to the mere corn and conon 
planter, may be no recommendation of it. 1 
will state, however, that in a field planned in 
cotton in 1844, and rested last year, which usu- 
ally produces a heavy crop of hog-weed, when 
turned out, there came up, although it had not 
been plowed at all, an uncommonly fine growth 
of crow-foot; which lean only account lor 
from its having been marled. The part longest 
marled had the best crow-foot. 
Lime is thought in England to prevent smut 
in wheat — to destroy many injurious insects — to 
preserve sheep pastured on land after its use } 
froni rot and foot-rot— and it is every where re- | 
garded as improving the heathlulness of drained 
lands. In short, it is flow generally agreed, not 
only by scientific men, but by the best and most 
experienced farmers in every part ot the w'orld 
where it has been properly tested, that “Lime 
is the basis of alt good husband''y,” in which ! 
opinion I fully and cordially concur. I 
In endeavoring to furnish you with something | 
like a theory of the action of Lime, I have sta- j 
ted some— perhaps many — things which are 
questioned by men ot great scientific attain- 
ments. Agricultural Chemistry — indeed, the 
whole science ot chemistrv — may be said to be 
yet in infancy. If it is difficult to penetrate the 
arcana of pa.‘^sive nature, it is far more so to in- 
vestigate those active operations which are 
conducted in the air and under the ground, in 
the formation of plants, complicated as ihey are 
in addition by the yet unknown vital agency of 
the plant itself. Although, on the whole, the 
an of agriculture has been vastly advanced by 
the discoveries and experiments of chemists, 
and he who shuts his eyes to the light they are 
constantly shedding for the benefit of farmers, 
is now, and will soon be much iarther, behind 
his age; still it is well known that great absur- 
dities have been put forward, and with the ut- 
most confidence, by the most eminent charac- 
ters in modern science. In speaking, then, of 
the peculiar action of any of the elements out 
ot which plants are formed, and its agency in 
the m vsterious operations consummated in the 
production of a full-grown, matured and fruit- 
bearing plant, it is not only becoming, but neces- 
sary, that every one, mo.st especially a mere 
farmer like myself, should express opinions 
with great diffidence and caution, and hesitate 
before drawing even from established facts, in- 
ferences of important and extensive bearing, i 
In view of this, I ought not to omit to state to j 
you, that within a few years past, a sweeping I 
theory has been suggested by one of the first j 
chemists and most popular writers of the age, i 
that has found some able supporters, and which 1 
if true apparently upsets every thing that has 
been said ot the effect ot lime in furnishing 
food logrowing plants out of decayed vegetable 
matter. Dr. Liebig asserts, that the decayed 
vegetable matter of the soil called humus, or 
mould, affords no direct nourishment wffiatever 
to plants. That they derive all their organic 
constituents from the atmosphere, and only their 
inorganic from the earth. The organic con- 
stituents of plants are those which are dissi- 
pated when they are burnt, and in most vegeta- 
bles amount lo from 97 to 99 parts in 100. The 
inorganic constituents compose the ashes which 
are left by fire, amounting usually from 1 to 3 
parrs in 100, in some rate cases to as much as 
12 per cent. The only nourishment which, ac- 
cording to this theory, the .soil affords to plants, 
being thus limited to from 1 to 3 parts in 100, the 
utmost direct influence of good or bad soils, of 
manure of all kinds— ot lime, alumina, silica, 
and all mineral elements — can reach no further 
than to the modification of an hundredth or at 
most a ihirty-ihird part of the crojrs we cultivate. 
It follows that the world has all this time labored 
under a most important error in estimating at 
such vastly different values, what we cal! rich 
and poor lands That the effects of manure are 
in a great measure fanciful, or at least that from 
1 to 3 lbs. ol ashes are equivalent to 100 lbs. of 
vegetable matter, as an application to the soil, 
and that it is useless labor to put on manure in 
any other form. Knowing as wedo that a single 
drop of prussic acid will almost instantly extin- 
guish life, it would not be lair to desy very great 
influence to even the smallest proportion of in- 
organic matter in the production ot plants. And 
since Liebig concedes that until the leaves are 
formed, the plant derives its carbonic acid from 
an artificial atmosphere generated by the con- 
tact of humus in the soil with the air, it would 
not be sate to denounce this theory in the present 
state of science, as absurd. It is admitted too 
on all sides that plants doassimilatecarbonirom 
the atmosphere, and it seems established that 
ammonia descends in rain water. However 
true this may be, and though Liebig’s theory 
was establi-shed as perfectly so in all its parts, I 
should think it most prudent to hold on still to 
what experience and rational deduction have 
taught us of the influence of vegetable mould 
on crops, in the hope that further discoveries 
might harmonize old facts and new truths, es- 
pecially as none of us would set about impro- 
ving the atmosphere, or desire to add more car- 
bonic acid or nitrogen to it, since any material 
increase of these elements w'ould render it fatal 
to animal lite. Indeed, no scientific discoveries 
or force of logic can ever, I am convinced, for 
an instant, shake your confidence or that of any 
practical farmer, in vegetable mould and com- 
post manure; or lead you to doubt that the 
amount of your crop, if properly tilled under 
fair seasons, depended in all other respects 
wholly and solely on the quality^3l your land. 
Whether the soil furnishes 1 part or 99 parts iu 
a hundred— you have too often seen plants on 
the same acre, subject to the same identical at- 
mospheric influences throughout, varying Irom 
good to worthless, according to the soil, to ques- 
tion the. important tact that by improving your 
land .you improve your crop in the same ratio 
prdcis’^, and that by exhausting it you equally 
deterioVaie the crop. 
In fact, depth ot soil, by which we mean 
depth of decayed vegetable mould mixed with 
sand, clay, &c., has been with you, as with all 
the world, heretofore, a criterion, and a never 
failing one, of the value of land, and so it will 
forever continue to be, I venture to assert. If 
then, as 1 believe, and you will probably agree, 
plants derive their most important constituents 
ot al! kinds from the soil and from vegetable 
mould, the value of lime in the soil is by no 
means limited to its action on the mineral or 
inorganic constituents of it, but ex ends to the 
production also of those organic elements 
which preponderate so immensely in all vege- 
tation. 
But your inquiry of me was in reference to 
Marl. I must therefore remind you again, 
that all which has been said of lime is true of 
marl. If it is .slower than lime in its early op- 
erations, that is more than compensated by ma- 
ny advantages which it possesses. This is be- 
coming so well understood, that wherever the 
same quantity of lime can be placed on land as 
cheaply in the form of marl, it is rapidly super- 
