Castor-Oil is extracted from the nut, or the seed of the

Ricinus communis, a native of the West Indies. These seeds are about the size, of small beans, which, In their brittle shells, contain white kernels, of a sweet; oily, but somewhat nauseous tat Nor is the expressed oil quite free from the acrimony of the nut; though it is, in general, one of the mildest, and safest purgatives; so that half a tea-spoonful for a dose has been given, with success, to new-born infants, for lubricating the first passages, and expelling the' meconium. It is also one of the best vermifuges, and a most efficacious remedy for the dry belly-ach, and iliac passion, when administered in proper doses, to children and adults; viz. the dose for the former, from one to two tea-spoonfuls ; and the latter, a table-spoonful, repeated every two or three hours.

As patients generally have a great aversion to this oil, in its pure state, it may be taken swim-ming either in a glass of peppermint, or simple water, or in the form of an emulsion, with mucilage, or with the addition of a small quantity of rum. The greatest precaution, however, is necessary with respect; to the quality of this oil, as there are two modes of preparing it, namely, by decoction and expression: the former is of a brown colour, has a rancid, dis-agreeable taste and smell, and consequently unfit for internal use ; whereas that obtained by expression, is more limpid, rather verging to a green colour, and almost tastes less; but, when spoiled by long keeping, it is likewise an improper medicine.

Externally, castor-oil warmed, and rubbed on the parts affected, has been successfully applied ill that painful spasmodic contraction, and rigidity of the muscles, called the tetanus; as likewise mixed with opium and camphor, in the form of a liniment, to relieve the most distressing spasms, and particularly the trismus, or locked jaw; in which cases, however, it possesses no specific action.