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knowledge of this process that we may lay down the follow-

ing rules in relation to it:

1st. The ground selected for the deposition of stable ma-
nure should be even, in order to permit the equal distribu-
tion of the manure on it, and thus secure to the heap, uni-
formity in thickness. Only in this case the process of pu-
trefaction will proceed regularly in every part of the heap,
and its body will prove to be of a homogeneous character.
2d. The manure should be protected against the direct
rays of the sun, in order to prevent the too rapid advance
of the putrefactive process, and a consequent generation of
heat which will incur a considerable loss of ammonia. Prac-
tical experiments made with equal weights of stable manure
exposed to the sun, and with that under cover, show the ef-
fect of the latter to be, within a certain time, about twenty-
five per cent, greater than the former.                             

3d. The manure heap should be kept moderately moist; if
it be too dry, the degree of heat then produced will volatize
ammonia; if too wet, an acid humus will be formed which,
being soluble in water, acts very injuriously on vegetation.
In order best to attain this end the ground should be slight-
ly inclined, and all the fluid that runs from the heap be col-
lected in a pit, from which it may from time to time be scat-

tered over the heap.

If the above rules are strictly observed, and the necessary
arrangements which they require to be made fairly provided
for, no other precautions need to be taken for securing the
highest possible effect of this manure. The practice of ap-
plying plaster of Paris, copperas, or sulphuric acid for the
purpose of fixing the volatile ammonia, is then unnecessary
and may best be entirely dispensed with, Indeed, the sul-
phate of lime, whether directly added in the form of plaster
of Paris, or subsequently produced in it by the application of
the other two substances, will be of good service only in the
case that enough of water is present to favor the formation

of sulphate of ammonia (a fixed ammoniacal salt) on one side,
and of carbonate of lime on the other If, on the contrary,
the heap should happen to remain dry for some time, the
effect produced by such applications will be quite the reverse.
Carbonate of ammonia is then evolved and sulphate of lime
regenerated; and a neglect of attendance to this condition,
therefore, much harder felt than when no applications of this
sort have been made to the heap at all.
We have thus far, exclusively treated of the organic part
of stable manure, particularly of its composition and the
changes to which it is subject by the process of putrefaction.