There are few animal substances of which the nature varies as much as that of urine; the quality of food or the state of health, produces a sensible change in it. The urine of animals is more or less abundant and active in its qualities, in proportion as their food is juicy or dry. Those which live upon dry fodder give less urine than those which are fed upon green herbage; but that of the first contains a greater quantity of salts than that of the last; and that which is produced directly by drink contains less animal matter than that which is secreted from the blood by the urinary organs. There are different states of individuals which may explain satisfactorily the disagreements in the results which have been given, by the numerous analyses which have been made of this fluid. Mr. Brandt has found the urine of a cow to contain:

Messrs. Fourcroy and Vauqueline have extracted from that of

Muriate of ammonia, free lactic acid, lactate of
ammonia, and animal matter

17.4

981.5

The remainder is composed of sulphates, phosphates, and muriates.

It may be seen from these analyses, that there is a wide difference in the urine of various animals, but that all contain salts which enter into plants, with the water by which they are held in solution; and draw in at the same time those animal portions, which like urea, are easily soluble, and can be decomposed without difficulty.

Amongst the principles contained in urine, there are some salts undecomposable by the digestive organs of vegetables; such are the

phosphate of lime, the muriate and the sulphate of potash. These can serve only to excite and stimulate the organs; but the urea, the mucilage, the uric acid and other animal matters, must be considered as eminently nutritive. Urine in its recent state should never be employed as manure; it acts with too much force, and has a tendency to dry the plants; it should therefore be either mixed with water, or allowed to ferment.

Urine is very useful for moistening all those substances which enter into composts; it increases the fertilizing properties of each one of them, and facilitates the fermentation of those which need to be decomposed before yielding their nutritive qualities.

Urine, when combined with plaster, lime, &c., forms a very active manure for cold lands.

Bones have, at the present time, become, in the hands of the agriculturist, a powerful agent in fertilizing the soil. These parts of animals are principally composed of phosphate of lime and of gelatine. Those bones which are most usually employed, contain about equal quantities of phosphate and gelatine; those of the horse from thirty-six to forty; and those of the hog from forty-eight to fifty.

The bones of young animals contain more gelatine than those of older animals, and have a less compact texture. The bones of the feet of the elk, roe-buck, stag and hare, afford, upon analysis, from eighty to ninety per cent. of phosphate.

When bones are to be employed as a manure, they should be ground fine, and thrown into a heap to ferment. As soon as this action shall have commenced, so as to give out a penetrating odor, the mass should be spread upon the earth, and be afterwards mixed with it. When seeds are sown in furrows, it is a good method to place some of the ground bones in the furrows with them.

In some countries the fat and a great part of the gelatine are extracted from bones; by boiling them in water, before selling them for agricultural purposes. But by this operation they are deprived of a great part of their fertilizing powers. Upon carefully observing the appearance of a mass of bones under fermentation, I found the surface of a part of them to be covered with a thin coating of an unctuous substance, sharp and biting to the taste. This appeared to me to be formed by the combination of gelatine with ammonias; the last being always developed during the decomposition of all animal substances. The observations of M. D'Arcet, to whom we are indebted for a very valuable work upon gelatine, support this opinion.

It is possible, that, when the ground bones are employed without having been first submitted to the commencement of a fermentation, the gelatine is gradually decomposed in the ground, and the same result at length produced; or, we can conceive that water, acting upon the bones, will dissolve the gelatine, and transmit it to plants; and in both these cases the influence of the bones upon vegetation is very great, whether it be considered as a purely nutri

tive manure, or in the double connexion of a nutritive and stimulating substance.

When bones are calcined in a close vessel, they yield oil and carbonate of ammonia; the proportion of the phosphate is not sensibly diminished; but the gelatine is decomposed. There remains after the operation, from sixty-six to seventy-two per cent. of the weight of the bones employed. This residue, broken and pulverized with care is of great use in the process of refining sugar.

After having been used in this process, and become impregnated with ox-blood and animal carbon, I have found it to be one of the best manures which I could employ for trefoil and clover. It should be scattered with the hand upon the plants, when vegetation begins to be developed in the spring.

Some of the dry parts of animals, as the horns, hoofs and claws, approach closely to bones in the nature of their constituent principles; but the proportions of this vary prodigiously. In such parts, gelatine constitutes the largest portion; and for this reason they are more esteemed for manure than bones. M. Merat-Guillot has found but twenty-seven per cent. of phosphate of lime in the hoof of a stag. And M. Hatchette, by an analysis of five hundred grains of the horn of an ox, gained only one-fifth part of earthy residuum, of which a little less than one-half was phosphate of lime.

The clippings and parings of horses form an excellent manure, of which the effect is prolonged during a succession of years, owing to the difficulty with which water penetrates them, and the little tendency they have to ferment.

A very good manure is likewise formed from wool. According to the ingenious experiments of M. Hatchette, hair, feathers and wool, are only particular combinations of gelatine with a substance analagous to albumen; water can only dissolve them by means of fermentation, which take place slowly, and after a long time. One of the most surprising instances of fermentation that I have ever seen, is that of a field in the neighborhood of Montpellier, belonging to a manufacturer of woollen blankets. The owner of this land causes it to be dressed every year with the sweepings of his workshops; and the harvests of corn and fodder which it produces is astonishing.

It is well known that the hairs of wool transpire a fluid which hardens upon their surface, but which possesses the property of being easily soluble in water. This substance has received the name of animal sweat; the water in which wool has been washed contains so much of it, as to make it very valuable as a manure.

I saw thirty years since, a wool merchant in Montpellier, who had placed his wash house for wool in the midst of a field, a great part of which he had transformed into a garden. In watering his vegetables he had used no other water than that of the washings; and the beauty of his productions was so great as to render his garden a place of general resort. The Genoese collect with care

in the south of France, all they can find of shreds and rags of woollen fabrics, to place at the foot of their olive trees.

According to the analysis of M. Vauquelin, this animal sweat is a soapy substance, consisting of a base of potash, with an excess of oily matter, and containing, besides, some acetate of potash, a little of the carbonate and of the muriate of the same base as scented animal matter.

The dung of birds is another very valuable manure, differing from that of quadrupeds in the food's being better digested, in containing more animal matter, being richer in salts, and affording some of the principles which are found in the urine of four-footed animals.

The dung of those sea-fowls, which are so numerous in the islands of the Pacific ocean, and of which the excrement furnishes an important article of commerce with South America, as according to the accounts of M. Humboldt, they import into Peru fifty ship loads of it annually, besides a great quantity of uric acid partly saturated by ammonia and potash, some phosphate of lime, or ammonia and of potash, as well as some oily matter. Davy found the dung of a cormorant to contain some uric acid.

The good effects resulting from the use of pigeons' dung in our country, has caused it to be carefully collected. One hundred parts of this, when fresh, yielded to Davy twenty-five parts soluble in water, whilst the same, after having undergone putrefaction, gave but eight; whence this able chymist concluded, with reason, that it was necessary to employ it before being fermented. This is a warm manure, and may be scattered by the hand before covering the seed, or it may be used in the spring upon strong lands, when vegetation appears languid.

The excrement of the domestic fowl approaches nearly in its qualities to that of the pigeon, without possessing the same degree of power. It contains also some uric acid, and may be applied to the same purposes as pigeon dung.

In the south of France, where they raise many silk worms, they make great use of the larvæ, after the silk has been spun from the cocoons. They are spread at the foot of the mulberry and other trees, of which the vegetation is in a languishing condition; and this small quantity of manure reanimates them surprisingly. Upon distilling some of these larvæ, I found more ammoniac than I have ever met with in any other animal matter.

Night soil forms an excellent manure; but farmers allow it to be wasted, because it is too active to be employed in its natural state, and they know not how either to moderate its action, or to appropriate it during different stages of fermentation to the wants of various kinds of plants.

In Belgium, which has been the cradle of enlightened agriculture, and where good modes of cultivation are continued and constantly improved, they make astonishing use of this kind of manure. The first year of its decomposition, they cultivate upon the soil to which

it is applied, oleaginous plants, such as hemp and flax; and the second year sow the land with corn.

They likewise mix water with the urine, and use it to water the fields in the spring, when vegetation begins to unfold. This substance is likewise dried and scattered upon fields of cabbage.

The Flemings value this kind of manure so much, that the cities set a high rate upon the privilege of disposing of the cleansings of their privies; and there are in each one of them, sworn officers for the assistance of those who wish to make purchases. These officers know the degree of fermentation suited to each kind of plant, and to the different periods in bringing this branch of industry to the same degree of perfection amongst us, that it has arrived at in Belgium, because our farmers do not realize its importance, and have a repugnance to employing this kind of manure. But could they not collect carefully all these matters, mix them with lime, plaster, or gravel, till the odor was dispelled, and then carry the whole upon the fields?

Already in most of our great cities, the contents of our privies are used for forming poudrette; this pulverulent product is sought for by our agriculturists, who acknowledge its good effects; let us hope, that becoming more enlightened, they will employ the fecal matter itself, as being more rich in nutritive principles, and abounding equally in salts; they can easily govern and moderate the too powerful action of this, by fermentation, or what is still better, by mixing it with plaster, earth, and other absorbents, to correct the odor.

As dung-hills are the riches of the field, a good agriculturist will neglect no means of forming them; it ought to be his first and daily care, for without dung there is no harvest. The scarcity of dunghills, or which is the same thing, the bad state of the crops, sufficiently proves the prejudices, by which the peasant is every where governed and the horticultural blindness with which he proceeds in his labors. In our country, many of those who cultivate the land, know only the kinds of straw which are suitable for furnishing manure, and in a dung-hill of litter, consider them as acting the principal part, whereas they are only feeble accessors.

According to the experiments of Davy, the straw of barley contains only two per cent. of substance soluble in water, and having a slight resemblance to mucilage; the remainder consists entirely of fibre, which can be decomposed only after a long time, and under circumstances calculated to facilitate the operation.

I do not believe that there is in the whole vegetable kingdom, an aliment affording so little nutriment, either for plants or animals, as the dry straw of grain; serving only to fill the stomachs of the latter, and furnishing to the farmer but one hundredth part of its weight of soluble manure.

Weeds, leaves of trees, and all the succulent plants which grow so abundantly in ditches and waste lands, under hedges, and by the road side, if cut or pulled when in flower, and slightly fermented,