284 
THE CULTIVATOR. 
abraded by the fury of the current, and there is reason 
to fear that the valleys of many of our streams will 
soon be converted from smiling meadows into broad 
wastes of shingle and gravel and pebbles, deserts in 
summer, and seas in autumn and spring.” 
The Law of Manures. 
We notice that the question—“ Do Manures Ascend 
or Descend?” has lately been considerably discussed. 
For our own part, we should no more think of asking 
or discussing such a question, than we should whether 
moisture ascends or descends ? It obviously does both ; 
and so it is with manures, unless the term manures is 
to be restricted to mineral substances only. 
But though we believe that the valuable parts of 
manures may be both carried into the air and washed 
into the earth, we do not admit the propriety of some 
positions, by which the fact is attempted to be illus¬ 
trated. For instance, it is said—“the gases of ma¬ 
nure ascend, but the salts descend.” The fact is here 
lost sight of, that the same substances are capable, 
under different circumstances, of assuming both a gase¬ 
ous and solid form. Such is the case with carbon,— 
which constitutes the greatest part of ordinary ma¬ 
nures, as well as vegetable substances; and also with 
nitrogen,—which has formerly been held by chemists, 
(and is, indeed, still held by many chemists,) as the 
most valuable and important element in manures. 
If a heap of manure is left to ferment on the surface 
of the earth, or without being covered by some absorb¬ 
ing substance, its bulk and weight are greatly reduced. 
What has become of the lost portion? It has, of 
course, gone into the air, as it would have done if the 
manure had been acted on by fire. The manure, or a 
certain portion of it, has been resolved into its original 
elements, and the carbon and nitrogen it contained 
have again become parts of the atmosphere. 
The nitrogen in manure is in the form of ammonia, 
and that it escapes during fermentation, has been 
proved ; it is perceptible by the smell, and has, also, 
by means of acids, been detected in its ascent. Most 
people are familiar with ammonia in the form of a salt, 
and know that in this form it is extremely volatile, and 
readily passes into an aeriform state. It is also easily 
soluble in water ; and is, therefore, readily washed 
into the earth by rains. Thus the very substance 
which forms a salt, may become a gas and ascend into 
the air; or it may become a liquid and descend into 
the earth. 
Manures may be combined with substances which 
will prevent the escape of ammonia ; such as charcoal, 
or charcoal-dust from coal-pits, peat, muck, soil, and 
vegetable or carbonaceous substances generally. If 
the process of fermentation is properly regulated, and 
the manure is combined with articles which will absorb 
the gases as they are disengaged, there will be no 
waste. It may be considered a rule, that whenever 
smell is emitted by manures, some of their valuable 
properties are being dissipated ; hence their odors 
should not be wasted “on the desert air;” they should 
be saved and converted into vegetable substances, in 
which condition they are not only more agreeable to 
the olfactories, but become substantial elements of 
animal nutrition. 
As to the sinking of manures, there is positive evi¬ 
dence of the fact. We have in many instances seen its 
effects to the depth of several feet. On the farm of 
Mr. Prentice, near this city, it was lately noticed, in 
digging a cellar near where a compost heap had laid, 
that the earth, to the depth of three feet from the sur¬ 
face, though it was of quite a compact and clayey na¬ 
ture, was so impregnated with the qualities of the ma¬ 
nure that they were plainly perceptible. And the ef¬ 
fects of manure are always traceable to a greater or 
less depth, in proportion to the porousness of the soil 
and the quantity of manure applied. It is Liebig’s 
opinion that the soluble parts of manures, “ phosphates, 
and other salts with alkaline bases,” are drawn off, 
and wasted to a great extent by percolation.* 
The depth to which manures should he buried is ano¬ 
ther subject, which, in connexion with the question, 
whether they rise or fall, has been much discussed ; 
and some, who believe that manures always ascend, 
have arrived at the conclusion that they should be 
placed from “ a foot to eighteen inches” under ground. 
We do not suppose it is practicable to lay down any 
fixed rule in regard to the covering of manures. Some 
general principles, however, may form a guide. It is 
evident that manures can only afford nutriment to 
plants when they are in a soluble condition. In their ap¬ 
plication, therefore, the causes which produce solution 
and decomposition should be regarded. These causes 
are, principally, heat, air and moisture; though in the 
elimination and assimilation of food by plants, light 
and electricity are evidently powerful agents. Most 
of these principles act with the greatest force near the 
surface. 
In some cases, as in dressing grass-lands, we would 
spread manures on the top of the ground. But in such 
cases, we would use a well-rotted compost, in which 
the animal manures had been combined with such sub¬ 
stances as would absorb the matters that during fer¬ 
mentation might pass off. The reason why we would 
prefer, for such a purpose, manure that had passed 
through the first stages of decomposition in the manner 
mentioned, is, that it would be more readily soluble, 
than in a fresher state, and would be immediately 
available to the crop ; while at the same time its fer¬ 
tilizing principles would be so far combined and fixed, 
as not to be liable to waste. 
But the practice of leaving manures entirely on the 
surface, is not, in many cases, the most judicious, for 
the following reasons : 1. If it is applied in an unfer- 
mented state, uncombined with absorbent substances, 
some of its valuable properties might be lost during 
decomposition. 2. With hoed crops, fresh or fibrous 
manures, on the surface of the ground, would be an 
obstacle, (more or less according to the quantity,) to 
cultivation. 3. Manures of any kind, or in any state, 
when left on the surface, might, from being kept too 
dry, fail to benefit the crop for which they were in¬ 
tended. Let it be recollected that they are only availa¬ 
ble to plants when in a soluble state; and to be made 
soluble, they must be kept moist. We would there¬ 
fore cover manures to such a degree as would secure 
the advantages and avoid the objections here indicated, 
and no more. 
On tenaceous soils, a mechanical effect is sought to 
be produced by manures; that is, a greater friability 
of the soil. This purpose is best accomplished by 
plowing in strawy or fibrous manures in a fresh or un¬ 
fermented state. This is obviously, however, quite a 
different thing from the application of manures to feed 
a crop. 
Exhibition of the Royal Agricultural Society. 
The exhibition of this society, for the present year, 
was held at York. It commenced on the 11th and 
closed on the 14th of July. The English papers speak 
of it as being “ the greatest of the ten meetings” which 
the Society has held. The number of entries for ani¬ 
mals was 725, and for implements 1508, The total 
amount bestowed in prizes was ,£2,295—($11,475,) 
of which £245—($1,225) was for implements. The 
number of animals and implements exhibited was much 
* See Liebig’s e s say on Artificial Manures.” Cultivator for 
1845, page 364. 
