(From the Arabic kira, or the Chaldean kera). Wax. It is a concrete collected from vegetables by bees, and extracted from their combs after the honey is separated from them. It is wholly a vegetable production: and a similar substance is obtained from leaves. A little of the pollen only is added by the bee, which gives the colour, and increases the solubility; for yellow wax melts at 142°; bleached wax at 155°. Wax is evidently an oil coagulated by oxygen, which it certainly contains, though, according to Lavoisier's analysis, 100 parts of wax consist of 82.28 of carbon, and 17.72 of hydrogen. In distillation, a little water and some sebacid acid come over, next a very fluid odorous oil, which increases in consistence till it assumes that of butter, and is called butter of -wax; but, by repeated distillations, Lemery reduced this to a very volatile oil. Acids have no effect on it: even the oxy-muriatic acid only whitens it. It is lighter than water, but heavier than proof spirit; and with the assistance of heat it is soluble in rectified spirit of wine; more so, according to Dr. Alston, than in oil. It is not at all soluble in aqueous liquors. With a small degree of heat it is dissolved into the appearance of a transparent oil; and in this state it is easily misci-ble with oils, and any kind of fat. It readily takes fire, and burns all away; and all the wax, like camphor, is volatile in a certain heat. Inflammable vegetable oils may exist under the various forms of oil, butter, balsam, wax, resin, and pitch, according, probably, to the proportion of oxygen which they contain.

Cera flava, yellow wax, in the state it is taken from the combs, is, while fresh, of a lively yel-low colour, tough, yet easy to break; hath an agreeable flavour, somewhat resembling honey: by long keeping it loses its colour, its agreeable smell, and becomes harder and more brittle. It contains, as we have said, a proportion of the pollen, furnished by the bee.

Distilled with water it impregnates the liquor with the smell, but gives no appearance of oil. If chewed, it proves tenacious, and neither mingles with the saliva, nor discovers any peculiar taste. By a mixture of gum arabic in fine powder it is rendered soluble in water; the wax requires its weight of the powdered gum for this end; and thus prepared, it is still insipid, and void of all acrimony. The addition of soap renders it also soluble in watery fluids.

Dioscorides observes that wax is healing and softening. When made into an emulsion, or mixed with spermaceti, in an electuary, or divided by rubbing it with the testaceous powders while it is in a melted state, it is successfully used to blunt the acrimony in diarrhoeas and dysenteries; it supplies the loss of mucus in the bowels, and heals their excoriations.

With soap, to which a small proportion of opium is added, or a few grains of Dover's powder, it becomes an excellent remedy for diarrhoeas of long continuance, and for dysenteries, when all obstruction and indurated faeces are removed. We have seen that it was formerly added to the vitrum antimonii, to mitigate its too great acrimony. Poemer used it in complaints of the bowels, by melting it with some fixed oil, and then combining it with water in an emulsion; but its union with soap, in pills, is preferable.

The college of Edinburgh gave the following preparation, in a former edition of their Pharmacopoeia. Pulvis testaceous ceratus. Testaceous cerated powder. - Melt yellow wax over a gentle fire, and carefully stir into it, by degrees, as much of the compound powder of crabs' claws as the wax will take up. The dose is a drachm twice a day.

The chief uses of wax are at present in plasters, ointments, and cerates, partly to give them consistence, and partly to increase their emollient and suppurating quality.

The college of physicians of London order an Em-plastrum cerae plaster of wax, formerly called em-plastrum attrahens, to be made of yellow wax and sheep's suet prepared, of each three pounds; yellow-resin, one pound; melted together, and the mixture to be strained whilst it remains in its fluid state. Ph. Lond. 1788. Though blisters used to be dressed with this plaster, it is not an agreeable form: softer and less adhesive cerates are preferable: the ceratum sper-matis ceti, or the ceratum resinae flavae,, are good substitutes for this plaster; which see, under Ceratum