(Quasi Castor 1754 from the belly, because of the largeness of his belly; or from castrando, because he is said to bite off his testicles, as the supposed object of his hunters). The Beaver, also called fiber, and canis ponticus. Castoreum russi-cum, materia, in folliculo prope anum sito, collecta. Pharmacop. Lond. Russian castor, from the castor fiber Lin. Systema Naturae. It is an amphibious quadruped, inhabiting some parts of Prussia, Poland, Russia, and Germany; but the greatest quantities are found in Canada. In the inguinal region of this animal are found four bags, of an oval shape, a large and a small one on each side; in the two large ones is contained a softish, greyish yellow, or light brown substance, which in a warm dry air grows by degrees hard and brittle, and of a darker and browner colour; this is the castor used in medicine. The two smaller bags have a smell much like that of the larger, but contain a softer and more unctuous matter of but little value.

On cutting these bags, when dry, and brought into the shops, they are found full of a brittle friable substance, of a brownish red colour, interspersed with fine membranes and fibres, intimately interwoven. Neumann asserts that the best comes from Prussia; all other writers say from Russia, and it is in hard round bags: an inferior moister sort comes from Dant-zic. The worst is from New England, which is in thin long bags.

The Russian castor hath a strong but not agreeable smell; the taste is pungent and bitter; the other sorts are weaker and more ungrateful.

Castor is ranked among antispasmodics, and is certainly, on many occasions, a powerful one. It has been useful almost in every case requiring such remedies, when given in doses of from 10 to 30 grains. In slow nervous fevers it takes off the oppression of the precordia, which is often a very troublesome symptom. It is by no means a stimulant, but seems rather to relieve by a sedative power. From this it is probably useful in stomach complaints: and if it be an em-menagogue, as authors have supposed, it must be in the hysteric and nervous habits, where the discharge has been repressed from spasm in consequence of a fright, or any similar cause. It has been styled also, without sufficient foundation, an aphrodisiac; but its quality of correcting the uneasy irritation of opium in those with whom that medicine disagrees, is an effect more firmly established. It is used in spasms and convulsions of every kind, in the flatulent colic, and in typhus. Joined with camphor, we have found it peculiarly useful near the conclusion of the more purely nervous fevers.

Rondeletius seems to have first made the distinction between these bags or glands of the beaver and his testicles, the part supposed to contain the castor. Alb. Seba remarks, that the Siberian castor is the best, and in succession, the Norwegian, the Swedish, the Polish, and the Canadian. But from whatever country it comes, that which is from a full-grown beaver, hath a fetid, disagreeable smell, an acrid biting taste, a brownish colour, and a friable texture, is the best.

It is adulterated with dried blood, gum ammoniacum, or galbanum, mixed with a little of the powder of castor, and some quantity of the fat of the beaver. But to detect the fraud, we may remark that the genuine follicules arise from one common source; that the matter contained in them is of a firm consistence, and too bulky to be introduced in their natural state: the smell is not so strong as the genuine. It is, indeed, sometimes difficult to distinguish the false from the genuine; but the sophistication is undoubted, when the membranes, pellicles, and fibres, do not appear intermixed with the castor.

This drug does not keep well in powder. Rectified spirit, proof spirit, and water, by the help of a little heat, extract its whole virtue. Rectified spirit takes up the less ungrateful parts, and water the more nauseous. Proof spirit acts equally, though with some difficulty, on both; the sp. ammon. compositus is an excellent menstruum, and in many cases improves its virtues.

The London college directs the following Tinctura Castorei.

Take of Russia castor, two ounces; of proof spirit of wine, a quart: digest for ten days without heat, and then strain. Dose 3i- to 3 iii- Heat only extracts the grosser part more plentifully than a cold maceration, and proof more than a rectified spirit. If it should be wanted to act more suddenly, the tincture of the Edinb. New Dispensatory, 1789, is preferable. Castor 1756 castorei

Russici Castor 1757 i. asafoetida ss. sp. sal ammoniac vinos. i. digere per sex dies.

Castor. See Cataputia major. Castratio, (from castro, to castrate). Castration. This operation, called also celotomia or-3 A 2 chotomia, is performed when the testicle is scirrhous or cancerous. When the testicle suppurates, it is only treated as a common abscess. Mr. Barnard says, that out of a hundred patients that he castrated, only three were living three years after: and that when, after the operation, the wound heals nearly, and not completely, it commonly proves mortal. Some of the most eminent practitioners observe, that when a scirrhous is extirpated, it is apt to return like a cancer in the breast.

But if the testicle must be extracted, first examine whether or not the spermatic cord is free. Should it not be so, the operation is useless. If not diseased, it must be laid bare, tied, and cut; after which all the diseased part of the scrotum must be dissected. If the tumour is large, or if it adheres to the skin, an oval incision must be made, begun a little above the tumour, for the better convenience of tying the vessel.

Mr. Gooch (Cases, vol. 2.) first slits the sheath of the cord with the point of a knife, then opens it further with a small pair of crooked scissors, by which method the vessel is fairly discovered, and easily taken up with a crooked needle and ligature. He adds, that if the whole spermatic cord be tied, the consequences are disagreeable, or perhaps fatal: he, therefore; after dissecting the sheath, secures only the artery, and thus an haemorrhage is prevented, and the usual consequences of tying the whole cord avoided. Dr. Hunter long since advised to secure the artery, and leave the rest of the cord; and, indeed, he suggests a sufficient security though the artery should be left untied; though if it is to be cut close to the ring, he advises to tie it before cutting, that it may not retract too suddenly, and prove troublesome by its discharge. Perhaps the scrotal arteries should be secured previous to the operation. After it, the patient should be kept perfectly quiet, and the wound healed, if sufficient integuments can be saved by the first intention. See Sharpe's Operations. Le Dran's Operations, and his 74th Obs. Heister's Surgery. Bell's Surgery, vol. i. p. 520.