“The origin of fat in the animal body has recently been made the subject of much animated discussion; on the one hand, it was contended that satisfactory evidence exists of the conversion of starch and saccharine substances into fat, by separation of carbon and oxygen, the change somewhat resembling that of the vinous fermentation; it was argued, on the other side, that oily or fatty matter is invariably present in the food supplied to the domestic animals, and that this fat is merely absorbed and deposited in the body in a slightly modified state. The question has now been decided in favour of the first of these views, which was enunciated by Professor Liebig, by the very chemist who formerly advocated the second opinion. By a series of very beautiful experiments, MM. Dumas and Milne-Edwards proved that bees exclusively feeding upon sugar were still capable of producing wax, which was pointed out as a veritable fact.”
Professor Liebig divided the principles found in food into two classes:—plastic elements of nutrition, or flesh-and-blood-making principles; and elements of respiration, or those which, by their decomposition or combustion in the system, generate heat. They are as follows:—
| Elements of Nutrition. | Elements of Respiration. |
| (Plastic or Nitrogenous.) | (Heat-producing.) |
| ———— | ———— |
| Animal flesh | Fat |
| Blood | Starch |
| Vegetable albumen | Gum |
| Vegetable casein | Cane sugar |
| Vegetable fibrin | Grape sugar |
| Milk sugar | |
| Pectin sugar | |
| Alcohol |
This division is in the main warranted by fact, but, no doubt, the nitrogenous elements of food produce heat as well as the non-nitrogenous.
NUX VOMICA. Syn. Koochla nut, Poison n., Vomit n.; Nuces vomicæ, Nux vomica (B. P., Ph., L., E., & D.), L. “The seed of Strychnos Nux vomica, Linn.” (Ph. L.), imported from the East Indies (B. P.). This drug is chiefly known as a violent excitant of the cerebro-spinal system. In small doses, frequently repeated, it is tonic, diuretic, and, occasionally, laxative; in slightly larger ones, it is emetic; and, in large doses, it is an energetic and fearful poison.—Dose, 1 to 3 gr.; in paralysis, nervous affections, impotence, chronic dysentery, chronic diarrhœa, &c. Its frequent use is said to render the system proof against the poison of serpents. See Strychnine, its active principle.
OAK. The British oak is the Quercus Robur of Linnæus, of which there are two varieties, Q. peduncata and Q. sessiflora. The wood of the oak is more durable than that of any other tree, and “for at once supporting a weight, resisting a strain, and not splintering by a cannon shot, it is superior to every other kind.” It, nevertheless, “warps and twists much in drying; and, in seasoning, shrinks about 1-32nd of its width.” Foreign oak is less durable, but more brittle and workable. The bark (OAK BARK; QUERCÛS CORTEX, QUERCUS—B. P., Ph. L., E., & D.) is used as an astringent and febrifuge, in doses of 30 to 120 gr., frequently; an astringent decoction is also made of it, but its chief employment is in tanning leather. The peculiar appearance of old oak or ‘wainscoting’ is given to the new wood by exposing it, whilst very slightly damp, to the fumes of ammonia.
OAT. Syn. Avena, L. The common cultivated oat is the Avena sativa (Linn.), a graminaceous plant, of which there are several varieties, as the Avena sativa alba, or white oat; A. s. nigra, or black oat; the potato oat, &c. Other species are also cultivated, as Avena nuda (Linn.), pilcorn, or naked oat;
A. strigosa, or Spanish oat, &c. The seed (OATS; CARYOPSIDES, SEMINA AVENÆ CRUDA) form the common horse-corn of this country, but in the northern parts of the country it is extensively used as food for man. The husked grain constitutes GROATS, and its meal OATMEAL. The latter does not form a dough with water, as wheaten meal or flour does.
Oats consist of from 24% to 28% of husk, and 74% to 78% of grain. According to M. Payen, they contain of starch, 60·59%; azotised matter, 14·39%; saccharine and gummy matter, 9·25%; fatty matter, 5·50%; cellulose, 7·60%; silica and saline matter, 3·25%. The husks contain between 6 and 7% of saline matter. (Prof. Norton.) The ash amounts to 2·18%, and consists of potassa and soda, 26·18%; lime, 5·95%; magnesia, 9·95%; oxide of iron, ·40%; phosphoric acid, 43·84%; sulphuric acid, 10·45%; chlorine,·26%; silica, 2·67%; alumina, ·06%. (Johnston.)
The yield of oats is from 20 bushels per acre in poor soils, up to 60, 70, and even 80 bushels per acre in rich soils. The weight per bushel varies from 35 to 45 lbs., and the product in meal is about one half the weight of the oats.