OL. 
AUGUSTA, GA., JULY 10, 1844. 
No. 14. 
DANA’S PRIZE ESSAY ON MANURES. 
(Concluded from page 102.) 
Section Eleventh. — Of Artificial Nllre Beds. 
But there is a fashion in manures as well as 
in other things, and saltpetre is now so fashiona- 
ble, that you may be inclined to use it. Be it 
so. I will show you, reader, how to make it 
for yourself, and at the same time form a large 
pile ol capital mould. But as you have began 
to inquire a little into the reason ofthing.s, let us 
go a little into the reasons why the earth under 
all barns where cattle are kept, why the plaster 
of old houses and cellar walls, always afford 
saltpetre. You well know that this is the case, 
and why f We have already told you that the 
acid of saltpetre, that is, the aquafortis, is form- 
ed of the air we breathe. Now alkalies and po- 
rous bodies compel the constituents of air, un- 
der certain circumstances, to unite and form 
aquafortis, and this immediately unites to the 
alkali and forms saltpetre. The best alkali to 
compel this union is ammonia. Hence, where 
plenty of animal matter is fermenting, or rot- 
ting, or where plenty of urine is, there, porous 
bodies being present, saltpetre will be formed. 
Now this is enough for you to understand the 
principle upon which I propose to you to form 
an artificial nitre-bed for your own use. It has 
been found that the manure of twenty-five cows, 
asses and mules, in layers of about four inches 
thick, with layers of the same thickness of 
chalky soil, first one and then the other, and now 
and then damped with the urine of the stable, 
produces from 1000 to 1200 pounds of saltpetre 
in four years. 
The heap is formed under cover, and occa- 
sionally shovelled over. At the end of two 
years, it is a mass of rich mould. It is loft two 
years longer, wnth an occasional turning over, 
but it is not wet with urine for the last few 
months. The dung the farmer has always; he 
wants the porous chalky body. This may be 
furnished by spent ashes, mixed up with its 
bulk of loam. Hence the following rule may 
be given : One cord of clear cow-dung, one cord 
of spent ashes, one cord of loam, or swamp 
muck. Mix the ashes and the swamp muck 
well, and having hard-rammed the barn cellar 
floor, or that under a shed, lay a bed upon it 
four inches thick of these mixed materials ; then 
a layer of dung, three or four inches thick, and 
so on, till the pile is two or three feet high, top- 
ping off with loam. Wet it occasionally with 
urine, keeping it always about as moist as gar- 
den mould. Shovel over once a fortnight for 
two years. The pile now contains about fifty 
pounds of several varieties of saltpetre, and 
mixed throughout with nearly three cords of ex- 
cellent manure. It may, therefore, be now used 
according to the farmer’s judgment. 
By thoughtful management, he may, after the 
first two years, annually collect as many fifty 
pounds as he emplo)'^s cords of cow dung, But, 
however prepared, nitre affords, by its elements, 
nourishment to plants. All its parts act. Its 
alkali acts, and its acid acts. 
Section Twelfth. 
Ashes. 
It is easy to see that salts, whatever be their 
name or nature, which are likely to be of any 
service to the farmer, are those only which eith- 
er enter into and form part of the plants, or 
which, by the action of their acid or base, act 
on the earthy parts of soil, or upon the mould. 
Salts either poison or nourish plants. The first, 
like the medicines we take, are good in small 
doses; the second can hardly injure, even by 
their excess. If we recur to the principle with 
which we set out early in this essay, that the 
ashes of plants contain all their salts, then right- 
ly to know what salts are likely to produce 
good effects as manure, we should first study the 
composition of ashes. We have in ashes a 
great variety of substances. They come from 
the soil. They form a part of plants. The 
dead plant returns them again to their mother 
earth, or we, losing the volatile parts of a plant, 
its mould and ammonia, by burning, collect its 
salts as ashes. Let us see what these salts are 
made of. In the first place, you know, all salts 
are composed of an acid and a base. 
The bases are, The o.cids are, 
Potash and soda, Carbonic, or carbon unit- 
Lime, ed to oxygen. 
Magnesia, Phosphoric or phosphorus 
Clay, do. do. 
Iron, Sulphuric, or Sulphur do. 
Manganese, Muriatic, essentially com- 
Silex, or earth of flints. po.sed of chlorine. 
Now if we throw out the carbonic acid, which 
has been formed in burning, we have left in ash- 
es three acids, which are united with the bases, 
and may form the following salts in plants, viz: 
Glauber’s salt, Epsom salt, common table-salt, 
bone-dust, asaltof lime, and what we may term 
a bone-dust salt of iron, or phosphate of iron, 
plaster of Paris, or gypsum, copperas, alum, 
and some other salts, which need not be enu- 
merated. Our list comprises the principal, and 
those most likely to be used in farming. Well, 
now, the lesson to be drawn from this composi- 
tion of ashes is this, that there is scarcely any 
salt occurring in commerce, which may not be 
used in agriculture, instead of those found in 
ashes. In fact, almost all salts which occur in 
a large way, as refuse materials from manufac- 
tures or other sources, have been used, and all 
with greater or less success, as manures. And 
if you cast your eye over the acids and bases of 
common ashes, this seems quite reasonable. It 
is not expected that a plain farmer, possessing 
little or no chemical knowledge, should be able 
to tell beforehand, what the effect of a salt would 
be, applied to his land; but if he understands 
what the composition of ashes is, he may be 
sure that in any quantity in which the salt is 
likely to occur, it cannot be injurious, provideil 
it is mixed up with plenty of mould, and a little 
ashes, or alkali, which will kill or neutralize 
any excess of the poisonous acid. 
In ashes, we have one part which may be 
leached out, and a part which remains after 
leaching, called spent ashes. Let us see, then, 
in leaching, what parts we take away. First, 
we take away all the acids, except the phospho- 
ric. Secondly, we take away nearly all the pot- 
ash and soda. What is left] The phosphoric 
acid, and all the bases. It is evident, theiefbre, 
that the strength of ashes can never be wholly 
leached out, if that depends upon the salts. In 
spent ashes we have nearly all the bone-dust 
left ; and besides this, a portion of what is usu- 
ally considered the real strength, that is, the pot- 
ash. This is chemically united to certain of 
the other constituents of ashes. You cannot 
leach it out. Upset your leach-tubs, shovel 
over your spent ashes, mix it up with ferment- 
ing manure, where a plenty of fixed air is given 
off. Here is the secret of the value of spent 
ashes, so far as the potash or ley strength is 
concerned. This exposure to air, to carbonic 
acid, lets loose the potash, which was chemical- 
ly combined with the other matters. Water 
would never have done this. Mark, now, a 
practical lesson taught here by chemistry, and 
confirmed by experience. Leached ashes must 
never be used on icel soil, if we want its alkali to 
act. The close wet soil, perhaps even half cc- 
vered at times with water, excludes the air. 
The carbonic acid of air, that which alone ex- 
tracts the alkali from spent ashes, cannot here 
act. There is this other lesson to be learned 
from these tacts, that it is chiefly the alkaline ac- 
tion which is wanted from spent ashes. Hence, 
no one who thus understands the source, and 
the true value of ashes, will allow the alkaline 
portion to be fir.st leached out, unless he can find 
a more economical use lor it than its applica- 
tion as a fertilizer. Perhaps no fact speaks 
louder, that the great action of spent ashes is that 
of its potash, than this, that where we prevent 
that from being extracted, the spent ashes are of 
little value. If, then, spent ashes derive their 
great value from the potash, much more will 
unleached ashes derive their value from their pot- 
ash. 
Now, reader, the point to which I have led 
you in these remarks, is this: that the more al- 
kaline any salt is, the better is it for manure. 
Hence, as a general rule about the use of salts, 
it may be laid down that the alkaline salts, that 
is, potash, pearlash, common ashes, barilla ash- 
es, white, or soda ash, are the best. And as 
these, in all their various shapes, are the cheap- 
est and most common articles, so you need not 
run after a long list of other salts. Next in 
value to the real alkalies, are spent ashes, used 
in a light, porous, open, sandy soil, if you would 
derive the greatest benefit from them. Next to 
these comes peat ashes. You well know these 
are of no value to the soap-maker. But not so 
to you. They show only traces of alkaline 
power. But treat them as you did spent ashes. 
Their pow'er, independent of their bone-dust, 
which is by no means small, and their plaster, 
which is still greater, and their lime, which is 
perhaps the greatest, lies in the alkali which is 
locked up, as it is in spent ashes. Treat them, 
therefore, as you did spent ashes, and then peat 
ashes will, and do, afford alkali. So too coal 
ashes, even your hard anthracite ashes, yield all 
the substances which sprnt ashes do. It is 
easily seen, therefore, when, how and where, 
spent ashes, peat ashes, coal ashes, are most 
likely to do good. Perhaps we may not have a 
better place to state the fact, that a cord of soap- 
boiler’s spent ashes contain about 50 pounds of 
potash. When we add to this, 117 pounds of 
bone-dust, and about a ton and a half of chalk, 
or carbonate of lime, which acts chiefly on the 
soil, and so comes not now under consideration, 
it is seen that there is no cheaper source of alka- 
li and salts, to one within reasonable carting 
distance of a soap-boiler, than spent ashes. 
They are marl, bone-dust, plaster, and alkali 
combined. 
Section Thirteenth. 
Manures composed chiefcy of Mould. 
These are of vegetable or animal origin. 
And first, of animal mould, Here we shaW find 
