parts of Europe, especially Italy, France, Spain, and Portugal, where it is cultivated to a very considerable extent, on account of its fruit, from which the sweet or salad-oil is extracted; and which also, when pickled, forms an article of food. This tree, however, produces no fruit in Britain, even in hot-houses, and as it is planted only in tree gardens of the curious, we shall confine our account to the properties of olives, and to the oil obtained from them.
Olives possess, in their natural state, an acrid, bitter, and extremely disagreeable taste; which, however, is considerably improved when this fruit is pickled. The Lucca olives being smaller than any other, have the weakest taste; the larger ones, imported from Spain, are the strongest; but the most esteemed are the olives of Provence, which are of a middling size, and not so strong as those of Spain.—On account of the great quantity of oil they contain, all these varieties, if eaten by persons of delicate habits, are extremely hurtful, especially if taken by way of dessert, after a solid or heavy dinner.—Olives pay, on importation, the sum of 1l. 18s. 912d. per hogshead of 63 gallons.
As an article of food, olive-oil is preferable to animal fat; but it ought always to be mild, fresh, and of a sweet taste. It should not, however, be eaten by persons of weak stomachs; for, even in its mildest state, it produces rancidiiy and acrimony, which are extremely injurious to digestion.—Olive-oil is chiefly used in salads, and should always be consumed together with a large portion of bread, or with the addition of sugar, on account of its richness; as otherwise it requires a powerful and active bile to assimilate it to alimentary matter. It pays on importation the sum of 7l. 7s. 912d. per tun of 252 gallons.
Medicinally considered, olive-oil has lately been found an excellent preventive of the plague, when rubbed over the whole body immediately after the contagion is supposed to have taken place.—It is also beneficially employed internally for recent colds, coughs, hoarseness, &c. whether mixed with water into an emulsion, by means of alkalies, or with conserves or syrups into a linctus.—Lastly, considerable quantities are used in the preparation of plasters, ointments, &c. for external applications.
Olive the Spurge. See Mezereon.
ONION, the Common, or Allium Cepa, L. an exotic plant, probably originating from Asia.
There are several varieties of the common onion, the principal of which are known by the names of Strasburgh, Spanish, and Egyptian. They are propagated by seed, which ought to be sown towards the end of February, or early in March, during dry weather; in the proportion of six pounds per acre, on light rich land, that has previously been well dug, levelled, and cleared from all weeds. In the course of five or six weeks, the onions will appear above ground; and, after growing a month, they will, in a good soil, admit of being hoed; wWch operation must be performed with a small implement, not exceeding 212 inches in breadth; and it will also be necessary to remove such as may stand too closely together, so as to leave the rest about three inches asunder. At the expiration of another month, the hoeing ought to be repeated, and the
