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As stock feeders in this way are commonly inclined to over feed, it is quite necessary to be attentive at all times to their conduct in this respect, as much of the advantage of the practice rests on it. In supplying the daily food great attention is also necessary. It should never on any account be suffered to remain for any length of time closely packed together in the carts or other conveyances, but be immediately spread out in its proper situations before the stock; and in order to save time and trouble, the best and most ready method would be to have the sizes of the carts or other contrivances for carrying it, adapted to the exact consumption of the stock, calculating for two or three fodderings, that the whole, or at least a certain part of it, may be at once readily and conveniently distributed to the cribs or racks of the houses or yards where the cattle are kept.

Where the supply of the day is collected at one time, the carts or other contrivances should be

provided with a number of light open frame divisions, according to the number of fodderings, in order that too much grassy matter be prevented from being packed too closely together, and that the several different portions may be thus more conveniently distributed out to the stock. It is material too, that the crops to be used in the soiling practice should not be suffered to advance too far in their growth before they are used, as by proper attention to this point they may be consumed by the cattle with more regularity, and with the least possible waste.

It is further particularly necessary to the perfect success of this practice, that the cattle themselves be kept quite clean and free from every sort of filth and nastiness, as well as their cribs, racks, boxes, or mangers, and other places; that there be plenty of good water for them to drink whenever they may be so disposed ; that their food be given to them as above without the least possible delay or injury; and that they be either wholly turned out into the yards constantly after eating their fodderings, or have the open air for some hours every day in the summer months in the cool of the evenings, and in the midday when the season becomes more cold. Advantages would also be produced in the condition and growth of the beasts, as well as in the increase of some of the products afforded by them, by having the different sorts of such keep properly varied and employed in alternation with each other.

ON ANIMAL MATTER.

All bodies endowed with life, and with spontaneous motion, are called animals. These are all capable of reproducing their life; some, by the union of the two sexes, produce small living creatures; others lay eggs, which require a due temperature to produce young ; some multiply without conjunction of sexes; and others are reproduced when cut in pieces, like the roots of plants.

All animals are fed on vegetables, either directly, or by the intervention of other animals. No one part of their substance is derived from any other source except water. The small quantity of salt used by man, and some other animals, is only necessary as a seasoning or stimulus to the stomach.

As the animal, then, is derived from the vegetable matter, we accordingly find that the former is capable of being resolved into the same principle as those of the latter. Thus, by repeated distillations, we obtain from animal substances, water, oil, air, an easy destructible salt and charcoal. These secondary principles, are, by farther processes, at length resoluble into the same proximate principles which we find in vegetables, viz., air, earth, and water, and the principle of inflammability.

But though the principles of vegetable and animal substances are fundamentally the same, yet these principles are combined in a very different manner. It is exceedingly rare that animal substances are capable of the vinous or acetous fermentation, and the putrefactive, into which they run remarkably fast, is also different in some particulars from the putrefaction of vegetables. The smell is much more offensive in the putrefaction of animal than of vegetable substances. The putrefaction of urine, is, indeed, accompanied with a peculiar fetor, by no means so intolerable as that of other animal matters ; this is, probably, owing to the pungency of the volatile alkali, and also to the urine containing less inflammatory matter than the blood and other fluids. When analysed by a destructive heat, animals afford products very different from those of vegetables ; the empyreumatic oil has a particular and much more fætid odour, and the volatile salt instead of being an acid, found as it is in most vegetables, is found in animals to be a volatile alkali.

Chemists have spoken of an acid procurable from animal substances, and indeed, certain parts of animal bodies are found to yield a salt of this kind ; but it by no means is the case with animal substances in general; and though the proofs to the contrary were even conclusive, it is confessedly in so small a quantity as not to deserve any particular regard. In some animals, however, an acid exists, uncombined and ready formed in their bodies. This is particularly manifest in some insects, especially ants, from which an acid has been procured by boiling them in water.

The solid parts of animal bodies, as the muscles, teguments, tendons, cartilages, and even the bones, when boiled with water, give a gelatinous matter or glue, resembling the vegetable gums, but much more adhesive. We must, however, except the horny parts and the hair, which seem to be little soluble either in water or in the liquors of the stomach. The acids, the alkalies, and quick-lime, are also found to be powerful solvents of animal matter. It is from the solid parts that the greatest quantity of volatile alkali is obtained; it arises along with a very fætid empyreumatic oil, from which it is in some measure separated by repeated rectifications. This salt is partly in a fluid, and partly in a solid state, and from its having been formerly prepared in the greatest quantity from the horns of the stag, it has been called salt, or spirits of hartshorn. Volatile alkali, however, is procurable from all animals, and from almost every part of an animal, except the fat. Though we are sometimes able to procure the fixed alkali from an animal cinder, yet it is probable that this salt did not make any part of the living animal, but rather proceeded from the introduction of saline matter, incapable of being assimilated by the functions of the living creature.

In speaking of the fluid parts of animals, we should first examine the general fluid from whence the rest are secreted. The blood, which at first sight, appears to be a homogenous fluid, is composed of several parts, easily separable from each other, and which the microscope can even perceive in its uncoagulated state. On allowing it to stand at rest and to be exposed to the air, it separated into what are called the crassamentum and the serum. The crassamentum consists chiefly of the red globules, joined together by another substance, called the coagulable lymph ; the chemical properties of these globules are not as yet understood, but they seem to contain the greatest quantity of iron found in the blood.

The serum is a yellowish subviscid liquor, having little sensible taste or smell ; at a heat of 160 Farenheit's thermometer it is converted into a jelly. This coagulation of the serum is also owing to its containing a matter of the same nature with that of the crassamentum, viz., the coagulable lymph ; whatever then coagulates animal blood, produces that effect on this concrescible part.

Several causes, and many different substances, are capable of effecting this coagulation, such as contact of air, heat, alcohol, mineral acids, and their combinations with earths, as alum, and some of the metallic salts. The more perfect neutral salts are found to prevent the coagulation, such as common salt and nitre.

Of the fluids secreted from the blood, there are a great variety in men and other animals.

The excrementitious and redundant fluids are those which afford, in general, the greatest quantity of volatile alkali, and empyreumatic oil. There are also some of the secreted fluids, which, on a chemical analysis, yield products in some degree peculiar to themselves. Of this kind is the urine, which is found to contain in the greatest abundance the noted salt formed from the phosporic acid and volatile alkali. The fat, too, has been said to differ from other animal matters in yielding, by distillation, a strong acid, but

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