<c TO IMPROVE THE SOIL AND THE MIND.” 
New Series. ALBANY, NOVEMBER, 1849. Vol. VI.—No. 11. 
Jorngn dorraponiaue. 
Letter from Prof. Liebig’s Laboratory. 
Giessen , August 20, 1849. 
Editors Cultivator —A voice from this quiet little 
town of Giessen, would scarcely have made itself heard 
amid the roar of revolution that has been corning to you 
for the last eighteen months. Who wanted to hear 
about chemistry, when all Europe had converted itself 
into a laboratory of decompositions and recompositions 
on a so much grander scale ? Meanwhile, things have 
moved on here very much as usual. The little town so 
well known to your readers through your old correspond¬ 
ent. Prof. Horsford, has, it is true, aroused itself suf¬ 
ficiently from its scientific repose, to amuse itself with a 
barricade or two in miniature,- hut, for the most part, it 
has been very quiet. An American can hardly compre¬ 
hend how, amid such stirring events, there is so little 
general excitement. At home, who would be satisfied, 
high or low, without having read the last paper, with¬ 
out being in possession of the last item of news. Here 
there is no such evidence of intense interest in the mass 
of the people. The old passivity hangs still around 
them. No one is satisfied with things as they were, or 
as they are; all would like to see a radical change, but 
where are the men inclined to act ? There are, it is 
true, a great many difficulties in the way of such a 
change. First of all, the fact that such a majority of 
the educated and influential among the people are di¬ 
rectly in the pay of the several governments; that is, 
are office-holders. Almost every profession is made in¬ 
to an office here. Clergymen and professors, for in¬ 
stance, are directly supported by government. One 
word too freely spoken, and the supplies are stopped, to 
say the least. Again, the ignorance of that large class, 
the peasantry, is a great obstacle in the way of a radi¬ 
cal change. Men must understand and feel their rights 
before they can assert them—they must feel their power 
also. Again, the strong sectional feeling. A revolu¬ 
tion arises for instance in Baden. The army passes the 
Hessian frontier, expecting support. Somebody calls 
the advance an invasion, and down comes the Hessians 
upon the invaders. In the Prussians, this sectional 
feeling may be dignified by the name of national pride. 
Not that they are proud of their king, but of the power 
of the nation. Authority brings them into the army, 
fear holds them there, and makes them the instruments 
©f the power they hate, and this petty gratification of 
pride of national power is their only reward. 
Prussia is said to be at present concentrating a large 
force upon the Austrian frontier. The prospect of this 
demonstration is sufficiently obvious. It is a terror for 
the south and east, in case of a refusal to come into the 
northern alliance. It is a good omen for Hungary, but 
for Europe, who shall say what it forebodes ? The 
south, involved as Austria is, in that most unjust of all 
wars with Hungary, cannot stand alone against the 
power of the north, but this does not make submission 
the more probable. May it not reckon with reason on 
foreign assistance ? Would England, France or Russia 
regard with indifference the increase of the power of 
Prussia, that woul'ff-result from such a war ? 
But enough of politics. Liebig’s summer course of 
lectures is nearly at an end. To-day, we had that most 
interesting chapter of modern science—the mutual re¬ 
lations of animal and vegetable life, particularly with 
reference to the atmosphere. In the hands of Liebig, 
this theme already trite, becomes invested with all the 
interest of a new discovery. And how beautiful m 
truth this arrangement of nature, according to which, 
each plant in its every breath, is a minister to the 
wants of animal life, purifying the air upon which k 
depends for existence, and in turn, deriving its own life 
and beauty from this act of beneficence. The discus¬ 
sion of the origin of the nitrogen of plants was one of 
the main points in this lecture. Liebig’s views on this 
subject are known to your readers, through his work 
on Agricultural Chemistry. The ammonia of the at¬ 
mosphere is a principal source. The determination of 
its amount recently made by Freseneus, may be inter¬ 
esting in this connection. He found about 1-3,000,000 
carbonate of ammonia in the air of the day, 1-2,000,000 
in night air. How such small quantities are estimated 
must appear mysterious to those unacquainted with the 
method of effecting it. The means are, however, very 
simple. To give an idea of the matter, we will sup¬ 
pose a hogshead filled with water, supplied with a cock 
below and an opening in the head above. On turning 
the cock the water runs out, and a corresponding vol¬ 
ume of air comes in above and takes its place. If 
the water that has escaped is measured, we know that 
foir every quart of it, we have a quart of air in the 
hogshead. Thus it is perfectly easy at any moment, t© 
know how 7 much air has come in through the opening 
above. Now we will suppose the hogshead full again, 
and to this opening a tube fitted, loosely filled with a 
substance that has such an affinity for ammonia, that it 
absorbs and retains all that approaches it. The cock is 
turned again; w r e let, say a hundred gallons of water 
run out and stop it off. One hundred gallons of air has 
consequently come in through the tube above, and left 
all the ammonia behind. We have the ammonia fast. 
All w-e have to do now is to weigh it; suppose it is a half 
grain; then a hundred gallons of air contain a half grain 
of ammonia. 
From a recent English paper, I see that the fabrica¬ 
tion of carbonate of ammonia, naptha, soda, &e., from 
peat, is commenced on a large scale in Ireland. The 
amount of the products must be overstated, but I be¬ 
lieve this manufacture might be pursued in America 
w 7 ith advantage. Ammonia has for years, been obtain¬ 
ed in large quantities, incidentally in the manufacture 
of burning gas from bituminous coal. It owes its ori¬ 
gin to the nitrogenized constituents of the plants from 
