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ON THE NATURE AND USE OF ANTI
ANTIMONY, when prepared in a certain manner, is so useful a medicine in veterinary practice, that every practitioner should understand its nature and properties.
If powdered antimony be exposed to a gentle fire, the sulphur exhales; the metallic part remaining in the form of a white calx, reducible, by proper fluxes, into a whitish brittle metal, called regulus. This is readily distinguished from the other bodies of that class by its not being soluble in aquafortis ; its proper menstruum is aqua regis.
If aquafortis be poured on crude antimony, the metallic part will be dissolved, and the sulphur thrown out, partly on the sides of the vessel, and partly to the surface of the liquor, in the form of a greyish yellow substance. This separated and purified by sublimation, appears in all trials the same with pure common brimstone.
The metal, freed from the sulphur naturally blended with it, and afterwards fused with common brimstone, resumes the appearance and qualities of crude antimony. There is a striking difference between the effects of the preparation of antimony on the human and brute stomach. To the former, the antimonial medicine is of the greatest power of any known substance. The quantity even of a single grain is capable of producing the most active effects if taken dissolved or in soluble state. If given in such a form as to be immediately miscible with animal fluids, it proves violently emetic; if so managed as to be more slowly acted upon, it proves cathartic; and if the dose be extremely small, diaphoretic.
Thus, though vegetable acids extract so little from this metal, that the remainder seems to lose nothing of its weight, the tinctures prove, in large doses, strongly emetic; and in smaller ones, powerfully diaphoretic. The regulus has been cast into the form of pills, which acted as violent cathartics, though without undergoing any diminution in their weight in their passage through the body, and this repeatedly for a great number of times. These preparations, however, exhibited to the horse, have a less sensible effect. Notwithstanding this, they are of great importance in the treatment of several diseases with which he may be afflicted. This metal, divested of the inflammable principle, which it has in common with other metallic bodies that are reducible to a calx, becomes indissoluble and inactive. The calx, nevertheless, when urged with a strong fire, melts into a glass, which is as easy of solution, and as violent in operation in the human subject, as the regulus itself; the glass, thoroughly mixed with such substances as prevents its solubility, as wax, resin, and the like, is again rendered mild.
Vegetable acids, as have already been observed, dissolve but an extremely minute portion of the metal; the solution, nevertheless, is powerful. The nitrous and vitriolic acids only corrode it into a powder, to which they adhere so slightly as to be separable in a considerable degree by water, and totally by fire, leaving the regulus in the form of a calx similar to that prepared by fire alone. The marine acid has a very different effect; this reduces the regulus into a violent corrosive; and though it unites with difficulty, yet it adheres so very closely, as not to be separable by any ablution, nor by fire, the regulus rising along with it.
The nitrous, or vitriolic acids, expel the marine, and thus reduce the corrosive into a calx similar to the foregoing. Sulphur remarkably abates the power of this metal, and hence crude antimony, in which the regulus appears to be combined with sulphur, from one fourth to one half its weight, proves altogether mild. If a part of the sulphur be taken away by such operations as do not destroy or calcine the metal, the remaining mass becomes proportionably more active. The sulphur of antimony may be expelled by deflagration with nitre; the larger the quantity of nitre to a certain point, the more of the sulphur will be dissipated, and the preparation will be more active.
If the quantity of nitre be more than sufficient to consume the sulphur, the rest of it, deflagrating with the inflammable principle of the regulus itself, renders it again mild.
The sulphur of antimony is likewise absorbed in fusion by certain metals, and by alkaline salts. These last, when mixed with sulphur, prove a menstruum for all metals, (zinc excepted ;) and hence, if the fusion be long continued, the regulus is taken up, and rendered soluble in water.
From these particulars, with respect to antimony, it may naturally be concluded, that it not only furnishes us with an useful and active medicine, but that it may also be exhibited for veterinary purposes under several different forms, and that the effects of these will be considerably diversified.
The College of Physicians have, in regard to human medicine, restricted the number of preparations of antimony in their pharmacopeia to a few only; and it is highly probable, that, from the proper employment of them, every useful purpose to be answered by antimony as a remedyin the diseases of cattle may be accomplished.
Calcined antimony is prepared in the following manner :
Take of antimony, powdered, eight ounces ; nitre, powdered, two pounds; mix them, and cast the mixture, by degrees, into a red-hot crucible. Burn the white matter about half an hour, and, when cold, powder it; after which, wash it with distilled water.
In the last edition of the London Pharmacopoeia, this preparation had the name of calx of antimony; and it may be considered as at least very nearly approaching to some other antimonials of the Old Pharmacopoeia, particularly to the nitrated diaphoretic antimony, washed ditto, and stibiated nitre, none of which are now received as separate formula of pharmacopoeia; and indeed, even the calx of antimony itself, thus prepared, has now no place in the Edinburgh Pharmacopoeia.
The calx of antimony, when freed by washing from the saline matter, is extremely mild, if not altogether inactive, in the human subject. For a man, the common dose is from five grains to a scruple, or half a drachm; and Wilson relates, that he has known it given by half ounces, and repeated twice or thrice daily for several days together. Some report, that this calx, by keeping for a length of time, contracts an active quality, from whence it has been concluded that the powers of the reguline part are not entirely destroyed; that the preparation has the virtues of other antimonials, which are given as alteratives ; that is to say, in such small doses as not to disturb the first passages. The uncalcined part being grosser than the true calx, the separation is effected by often washing with water, in the same manner as is directed by separating earthy powders from their grosser parts. It has been observed, that when diaphoretic antimony is
prepared with nitre abounding with sea-salt, of which all the common nitre contains some portion, the medicine has proved violent. This effect is not owing to any particular quality of the sea-salt, but to its quantity, by which the proportion of the nitre to the antimony is rendered less.
The nitrum stibiatum, as it was called, is produced by the deflagration of the sulphur of the antimony with the nitre, in the same manner as the sal polyche st, from which it differs no otherwise than in retaining some portion of the antimonial calx. Notwithstanding the doubts entertained by some of the activity of the antimonium calcinatum, yet the London College appears to have done right in retaining it ; for whilst it is allowed to be the mildest of our antimonials, it is admitted, by several able practitioners, to be efficacious.
CROCUS OF ANTIMONY.
Take of antimony, powdered, and nitre, powdered, of each one pound; sea-salt, one ounce: mix, and put them by degrees into a red-hot crucible, and melt them with an increased heat ; pour out the melted matter, and when cold, separate it from the scoriac.
Equal parts of antimony and nitre are to be injected, by degrees, into a red-hot crucible; when the detonation is over, separate the reddish metallic matter from the whitish crust, beat it into powder, and edulcorate it by repeated washings with hot water till the water comes off tasteless. Here the antimonial sulphur is almost totally consumed, and the metallic part left divested of its corrector. These preparations, given from two to six grains, generally act as violent emétics, greatly disordering the constitution. But the opera