All these new properties which the limed soil has acquired, doubt¬ 
less explain in part the fertilizing means which calcareous agents 
bring to the soil: but we think it is still necessary to seek some of 
these causes elsewhere. . „ , 
26. Lime, according to the recent discovenes of German che¬ 
mists, seizes in the soil the soluble humus or humic acid, takes it 
from all other bases, and forms a compound but slightly soluble, 
which appears, under this form, eminently suitable to the wants of 
plants. But as this compound is not soluble m less than 2,000 times 
its weight of water, while without the lime the humus is soluhle in a 
volume of water less by one-half, it would follow that, in conse¬ 
quence of lime, the consumption of this substance, and the produc¬ 
tive power of the soil would, in like proportion, be better preserved. 
Since the products of the soil increase much from the liming, while 
the humus is economised, since these products borrow very little 
from the soil, which remains more fertile while thus yielding greater 
products, it follows that the principal action of the lime consists, at 
first, in augmenting, in the soil and in the plants, the means of 
drawing from the atmosphere the vegetable principles which ley 
find there; and next, in aiding, according to the need, the forma¬ 
tion, in the soil or the plants, the substances which enter into h 
composition of plants,, and which are not met with ready formed 
either in the atmosphere or in the soil. . . 
The researches upon these various points are curious, important, 
interesting to practice as well as to science—and will lead us to ex¬ 
plain, by means not yet appreciated, the action ol lime upon vegeta- 
ABSORPTION BY PLANTS OF THE PRINCIPLES OF THE ATMOSPHEPE, 
IN THE VEGETATION ON UNCULTURED SOILS. 
29. Saussure has concluded, from his experiments, that plants de¬ 
rive from the soil about one-twentieth of their substance; and the 
experiments of Van Helmont and of Boyle have proved that consi¬ 
derable vegetable products diminish very little the mass of the sod. 
But this fact is still better proved by the observation of what passes 
in uncultivated soils. . 
Woodland that is cut over in regular succession, (taillis) produces 
almost indefinitely, without being exhausted, and even beconnn 
richer, the mass of vegetable products which man gathers and re¬ 
moves, and of which the sod does not contain the principles. If, in¬ 
stead of woodlands thus partially and successively cut over, we con¬ 
sider upon the same soil a succession of forests, and, for greater 
ease of estimation, resinous forests, we find for the product* of the 
generation of an age, forty to fifty thousand cubic feet to.the.hec¬ 
tare. This product is less than that of the resinous forests of many 
parts of the country, and yet it is nearly equal in bulk to half of the 
layer of the productive soil itself; it represents an annual increase 
0^24,000 weight of wood to the hectare-and which ^ produced not 
only without impoverishing, but even whde enriching the soil, by an 
enormous quantity of droppings and remains of all kinds. 
These products which do not come from the soil, are then drawn 
from the atmosphere, in which plants gather them by means of par¬ 
ticular organs designed for that use. These organs are the myria 
of leaves which large vegetables bear—aerial roots, which gather 
these principles either ready formed in the air, or which take up 
there the elements, to combine them by means of vegetable power. 
But these aerial roots exert quite a different and superior energy 
in gathering the constituent principles of plants m the atmosphere, 
to that of the roots in the ground—since the' 1 fo ™ er 1 J“™“JLwbut 
the whole amount of the vegetable mass, while the latter draw but 
very little from the soil. f 
30. Plants may well find in the atmosphere the greater part of 
the volatile principles which compose them—the carbon, hydrogen, 
oxygen, and azote. But it is not so easily seen whence they obtain 
the fixed principles of which their ashes are composed. These pro¬ 
ducts could not exist ready formed in the soil-for the saline- princi¬ 
ples contained in the ashes of a generation of great trees, which wou 
amount to more than 25,000 weight to the hectare, would have ren¬ 
dered the soil absolutely barren, since, according to the experiments 
of M. Lecoq of Clermont, the twentieth part of this quantity is 
enough to make a soil sterile. We would find a similar result in 
accumulating the successive products of an acre of good meadow. 
It is then completely proved that the saline principles of plants do 
not exist ready formed in the soil. They are no more formed in the 
atmosphere, or the analyses of chemists would have found them 
there. However, as the intimate composition of these substances 
is not yet perfectly known, their elements may exist m the atmos¬ 
phere, or even in the soil, among the substances which compose 
^Neither can it be said that these salts may be derived from the 
atomic dust which floats in the air; for this dust is composed of frag¬ 
ments organic and inorganic, carried especially to the plants them¬ 
selves, and then, in estimating this atomic matter at the most, we will 
scarcely find in it the hundredth part of the saline substances con¬ 
tained in the vegetable mass produced. We ought then to con¬ 
clude that the saline substances of plants are formed by the powers 
of vegetation or of the soil. „ 
31 In like manner as with the salme principles, the lime and the 
phosphates which are formed in ashes ought to be due to the same 
forces, whether the roots take up their unperceived elements m the 
soil, or the leaves gather them in the atmosphere. This conse¬ 
quence results evidently from this fact—that plants grown in soils, 
of which the analysis shows neither lime nor the phosphates, con¬ 
tain them notwithstanding in large proportion in their fixed princi¬ 
ples—of which [or of the ashes] they often compose halt the mass. 
THE SHEEP.— {Continuedfrom page 100.) 
PASTURE. 
Pasture has a far greater influence on the fineness of the fleece. 
The staple of the wool, like every other part of the sheep, must in¬ 
crease in length or in bulk when the animal has a superabundance 
of nutriment; and, on the other hand, the secretion which forms the 
wool must dqprease like every other, when sufiicient nourmshment 
1S When little cold has been experienced in the winter, and vegeta¬ 
tion has been scarcely checked, the sheep yields an abundant crop 
of wool, but the fleece is perceptibly coarser as well as heavier. 
When the frost has been severe and the ground long covered with 
sn ow—if the flock has been fairly supplied with nutriment,- although 
the fleece may have lost a little in weight, it will have acquired a 
superior degree of fineness, and a proportional increase of value 
Should, however, the sheep have been neglected and starved duru D 
this prolongation of cold weather, the fleece as well as the carcase 
is thinner, and although it may have preserved its smallness of fila¬ 
ment, it has lost weight, and strength, and usefulness These are 
self-evident facts, and need not to be enforced by any labored argu- 
ment; and therefore it is that since the sheep-breeder, living in a 
populous country, has begun, and judiciously so, to look more to the 
profit to be derived from the carcase—since the system of artificial 
feeding has been brought to so great perfection and a larger and 
better animal has been earlier sent to market, and a far greater 
number of sheep can now be fed and perfected on the same number 
of acres, the wool also has been somewhat altered m character—it 
has grown in length, and it has increased in bulk of fibre. It has 
not deteriorated, but it has changed. If no longer fit for the purposes 
to which it was once devoted, it has become suited to others. If it 
no longer brings the extravagant price it once did, it meets with a 
readier sale. The increase of the number of fleeces, and the in- 
crease of weight in each fleece, go far to compensate for the dimi- 
nution of price, while the improvement of the carcase more than 
supplies the deficiency, if in truth there were any : so that, consi¬ 
dering the badness of the times, and the state of agriculture gene¬ 
rally, the sheep is comparatively more valuable to the breeder than 
he was before. This will be touched on at greater length when the 
various breeds of British sheep pass in review, and their present 
state and produce is compared with what they were halt a century ago. 
Wool is now the subject of consideration, and there can be no 
doubt that in Great Britain it has materially changed its character 
since the introduction of artificial food, and the adoption of the forc¬ 
ing system. Mr. Nottage states, of the Western Down sheep, 
that he used to get one-eighth part of the finest English wool from 
each fleece ; but that now the quantity is so small that he does not 
throw it out: he does not set a basket for it at all 
savs that “ Thirty years ago there was, in some South Down flocks, 
Sy aVgood wool grown, as the fine German that now comes in¬ 
to our country.” Mr. Varley adds, that “ he used to throw his woo 
extremely high to the sort-very good to the sort-but he found that 
the qualities generally were getting so low, that if he continued that 
heLuld ifave been look™; .mo f 
hins without findino- a bit of wool in them. Mr. P ison states ot 
tlm Norfolks, that ‘‘in 1780, 4201bs. of clothing wool grown in Nor¬ 
folk would produce 2001bs. prime—m 1828, it would produce only 
141bs.” 
