1854. 
THE CULTIVATOR. 
Gypsum and Ammonia. 
Messrs. Emtors—-As the time of making compost 
is at hand, and the use of gypsum as one of their ingre¬ 
dients, has lately been decried, I take the liberty of 
giving you the substance of the results of some exper¬ 
iments recently madef bear ip g upon that point. 
It is well known to the most of farmers, that during 
the decay of animal and vegetable matter, a quantity 
of ammonia is found which from its volatile nature 
is very liable to evaporate, or pass away in the atmos¬ 
phere, very much to the deterioration of. the value of 
the substance as a fertiliser, for ammonia is a very 
beneficial manure. The form in which it flies away, 
is generally that of carbonate of ammonia, a very 
volatile pungent salt known under the name of harts¬ 
horn. Various means have been "suggested and used to 
fix this, that is, to render it less volatile and keep it in 
the material in which it is formed for the purpose of us¬ 
ing its valuable compounds as fertilisers. A common 
way has been to mix gypsum (sulphate of lime) with 
the material used in compost heaps, when a mutual 
decomposition takes place, in which carbonate of lime 
and sulphate of ammonia was, formed. This last salt- 
is much less volatile than the Other compound of am¬ 
monia mentioned, and is therefore more easily retain¬ 
ed in the heap. It has recently been denied in a sci¬ 
entific journal, that this change doestake place—-that? 
dry‘or nearly dry carbonate of ammonia will decom¬ 
pose and be decomposed by gypsum, and therefore 
that it would not fix the ammonia, and that its addi¬ 
tion toother manure, added to its value, only by its 
own ingredients“not by saving other valuable pro¬ 
ducts. 'This statement has been copied in several pop¬ 
ular newspapers, and if incorrect should be refuted, as 
it pretends to be based upon the unerring laws of chem¬ 
istry. 
I took three samples of gypsum, (the common, such as 
is used here by, the farmers,) arid tieated them with 
cai'bonate of ammonia in different ways, imitating the 
condition of the compost heap. The first I moistened 
slightly after mixing the two together, not making 
them more damp than they would be in a heap of 
compost., 
The second, I left dry as they were mixed. 
In the third, I did not allow the two to come in con¬ 
tact, at, all, but kept them separated, so that to unite, 
the carbonate of ammonia must come in contact with 
the gypsum as if evaporated.. 
In all .three cases, I exposed them a few days to 
air mixed with carbonic acid (conditions always pres¬ 
ent in the compost heap,) at the ordinary temperature 
of my room, and then exposed them to the pure air 
until the carbonate of ammonia had all been decom¬ 
posed (or evaporated,) and afterwards examined them 
chemically. In nil cases'a mutual decomposition 
had taken place. The gypsum (which was originally 
present in the largest quantity,) contained much car¬ 
bonate of lime, and a corresponding (apparently so at 
least,) amount of sulphate of ammonia was present in 
the mixture, which I separated by chemical means, and 
As I have remarked, the gypsum was present in ex¬ 
cess,.and so it should be in the compost heap.—that is, 
there should be more than enough present to decom¬ 
pose all of the ammoniacal compound. Otherwise 
there will be some that will escape, and undoubtedly 
a small quantity always does escape,; not coming in 
contact with anything which will retain it, for it is dif¬ 
ficult to have such substances thoroughly mixed thro’ 
the mass. 
I think these experiments show that the use of plas¬ 
ter, or gypsum, for this purpose, is founded on sound 
principle's, and consequently are safe to follow. Such 
experiments have been frequently made by others, and 
I intend if possible, the coming summer to carry on 
these further, and see if such changes do actually take 
place in fermenting and decaying barti-yard manure, 
the result of which you shall have, if you think them 
worth your attention. Yours truly, Wat. H. Brewer. 
Stumps and Simple Stump Machine. 
Messrs. Editor?) —In your paper of the 27tk, is an 
article on the decay of stumps, which I cannot allow 
to pass without having a kick at it. Stumps should 
never be induced to rot above ground, but below ; nor 
with the exception of sugar tree, should fire ever be 
applied to them. In clearing, all trees less than two 
feet in diameter, should be cut 18 inches from the 
ground, and the edges of the stump nicely bevelled 
with the axe, so that the doubletrees in plowing may 
slide freely over them. If the earth is kept, well dug 
with the mattock, and soft, about them, the roots will 
decay in a few years, so as to admit’ of their easy re¬ 
moval. Very Ihrge trees need not be cut so low, be¬ 
cause it is impossible for the team tb straddle them; 
and it is best to have them so high that your horses 
will not attempt that feat, if the driversheuld .be so 
careless as to permit them. An easy mode of produc¬ 
ing rapid decay in large stumps, is to split them by 
blasting with ’powder, thus admitting the rain and 
melted snow to penetrate to their main or tap roots. 
The cheapest'and most convenient stump machine 
for the farmer’s use, consists of a stout pole 18 or 20 
feet long, and a very strong log chain with which to 
fasten one end of the pole to the stump. A yoke of 
oxen hitched to the other end and driven around, soon 
twists the stump out of its bed. Occasionally some 
digging and cutting of roots will be neccessary to facil¬ 
itate this last operation; but if stumps are properly 
grubbed about, in the first plowing of the ground, they 
can be taken out when the ground is soft, in the spring 
or autumn, with very little trouble. Paul A. Way. 
Smiickly Valley , Pa. 
Plant a Tree. —As an encouragement to every 
body to plant a tree, the Prattsville Advocate states 
that there is now standing near Grace Church in that 
village, a tree which was planted by three little bojos 
forty-four years ago this spring, which measures thir¬ 
teen feet in circumference and is estimated to contain 
four cords of wood. One of the boys who helped to 
plant this tree, still lives in the village. 
