Domestic Encyclopædia (1802)/Castor-oil

CASTOR-OIL is extracted from the castor nut, or the seed ot 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 taste. 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 swimming either in a glass of pepper-mint, 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, disagreeable 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 tasteless; 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 in 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.