Castoreum russuum Pharm. Lond. Casto-reum Ph. Edinb. Castor: the inguinal glands of the castor or beaver; a four-footed amphibious animal, frequent in several parts of Europe, and in North America. These glands are of different shapes and sizes, covered with a thick skin, including an unctuous liquid matter, which in keeping grows dry and hard: on cutting the dry cods, as they are called, they are found full of a brittle friable substance, of a brownish red colour, interspersed with fine membranes and fibres exquisitely interwoven. The best caftor comes from Russia in large, round, hard cods; an inferiour sort, smaller and moister, from Dantzick; the worst of all from New England, in longish thin cods.

Aq. Caffiae figneae Ph. Ed.

Russia caftor has a strong not agreeable smell, and a biting bitterish nauseous taste: the other sorts are weaker than that of Russia, yet more ungrateful. It is generally looked upon as one of the capital nervine, antispasmodic and antihysteric medicines: its virtues have undoubtedly been much exaggerated; but though they are not near so great as they have by most writers been represented, they appear neverthe-less to be considerable. The common dose is from two or three grains to a scruple; though it has been sometimes taken by drams, and these doles very often repeated (a).

Rectified spirit, proof spirit, and water, extract, by the assistance of heat, nearly all the active matter of castor: rectified spirit dissolves mod readily the finer and less ungrateful, and water the more nauseous bitter part: proof spirit acts equally, but difficultly, on both. Of the two colleges, that of London directs proof spirit as the mensftruum, in the proportion of two pints to two ounces of the castor; that of Edinburgh, rectified spirit, with half as much more of the. castor. On digesting in the two spirits equal quantities of the powder, with equal degrees of heat, for ten or twelve hours, the tincture in proof spirit proved sensibly mod ungrateful, and that in rectified spirit possessed most perfectly the specific flavour of the castor:

(a) J. Marius, Castorologia aucta ab J. Franco, p. 74.

Tinctura caftorei Ph. Lond. & Ed.

an infusion in boiling water was bitterer and more nauseous than either. The castor remaining after the action of water, retained a little of its flavour, but nothing of its nauseous bitterness: that left by rectified spirit retained a little of the latter, but nothing of the former.

In distillation, it gives over to water the whole of its smell and flavour: a quart of water, distilled from an ounce of Russa castor, receives a considerably strong impregnation, but gradually loses greatest part of it in being kept. It is said, that on submitting to this operation large quantities of the castor, a small portion of essen-tial oil is obtained, which smells exceeding strongly, and diffuses its ungrateful scent to a great distance(a). This odorous and most active principle of the castor is carried off by water in a very gentle heat; infusions or light decoctions, which are very nauseous, yielding, however slowly infpiffated, a brittle extract, which has nothing of the specific flavour of the drug, and proves in taste but weakly though ungratefully bitterish. Rectified spirit on the other hand, distilled from the tincture made in that menstruum, brings over scarcely any sen-sible impregnation; nearly all that it had extracted from the castor, remaining entire in the infpiffated mass, which proves of an unctuous consistence; not easily reducible to dryness.

Castor is commonly joined in prescription with the deobstruent fetid gums, volatile alkaline salts, the volatile oily spirits, and other materials of similar intention. The volatile oily spirits are well adapted also as menstrua for dis-solving the active matter both of the castor and of the fetid gums; at the same time that they prove in many cases excellent additions to their virtue, as particularly in some hysteric disorders, and the several symptoms which accompany them: in this view, an ounce of Russia castor, and half as much afafetida, are digested about six days, in a close vessel, with a pint of the volatile spirit.

(a) Cartheufer, Fundamenta m. m. sect. xii. cap. 48.

Casumunar. Bingalle; Risagon. Cas-munar: the root of an East India plant, of which we have no certain account; brought over in irregular slices of various forms, some cut transversely and others longitudinally: the cortical part is marked with circles, and of a dusky brownish colour: the internal part is paler, and unequally yellow.

This root was introduced some time ago by Marloe, as a medicine of uncommon efficacy in hysteric, epileptic, paralytic, and other nervous disorders. At present it is sometimes employed as a stomachic, but its use is not yet become lb general as it seems to deserve. It is an elegant mild aromatic, moderately warm, lightly bitterish, in smell somewhat resembling ginger. Its virtues are extracted in perfection by rectified spirit, and, on drawing off the menstruum from the filtered tincture, remain concentrated in the infpiffated mass; which smells very agreeably, and impresses on the organs of taste a grateful bitterishness, and a durable glowing warmth, not a fiery or pungent heat. Both the tincture and extract are of a deep saffron colour.

Tinct. cas tor. comp. Ph. Ed.