"Take of sulphuret of antimony in coarse powder, one part; hartshorn shavings, two parts. Throw the mixture into a wide iron pot heated to redness, assiduously stirring until the sulphurous vapours cease to be extricated, and the matter acquire a grey colour. Rub the mass to powder when it is cold, and put it into a coated crucible; over which invert another crucible having a small hole in its bottom, and lute the two firmly together. Roast the matter with a heat gradually raised to whiteness for the space of two hours; and lastly, when it is cold, grind it to a very fine powder."

In these processes, by the first exposure of the materials to the action of heat, the gelatin and the other principles of the hartshorn, except the phosphate of lime, are decomposed and dissipated; the sulphur of the sulphuret of antimony is at the same time expelled, and the metal is oxidised, the oxidisement being favoured by the frequent stirring. By the subsequent application of heat, the oxidisement of the metal is rendered more complete, and antimonious acid is formed. The phosphate of lime is merely mechanically mixed with the acid. In the Dublin formula, the boiling of the hartshorn shavings ordered is unnecessary, as the heat effectually decomposes the gelatin, which is the only part of them that can be extracted by the boiling. There is great uncertainty in this preparation. In two specimens analysed by Mr. Phillips, the one yielded 35, and the other 38 per cent, of antimonious acid. According to that chemist, the antimonial powder is a compound of 1 eq. of antimonious acid = 161.2+ 1 of phosphate of lime = 99.9, making the equiv. 260.11.

From this uncertainty of uniformity in a preparation by the agency of fire, Mr. Chenevix proposed the substitution of a, powder prepared according to the following formula : - Let equal parts of white oxide of antimony and of phosphate of lime be dissolved in the smallest possible quantity of hydrochloric acid, and pour the solution into a sufficient quantity of distilled water containing pure ammonia in solution. A powder precipitates, which is a mechanical mixture of chloride of antimony and phosphate of lime.1 The process by heat, however, is still continued in the pharmacopoeias, from a desire of imitating, as closely as possible, the celebrated empirical preparation of Dr. James, "James's Powder," as a substitute for which this preparation was first introduced: and which, according to the analysis of Dr. Pearson, consists of 43 parts of phosphate of lime, and 57 of oxide of antimony, in 100 parts; or, according to Mr. Phillips, of 56 of antimonious acid + 44 of phosphate of lime, in 100 parts.2

Qualities. - The antimonial powder of the pharmacopoeias is inodorous and insipid, of a dull white colour, insoluble in water, and only partially soluble in acids: in this particular differing from the powder of Chenevix, which is solublein every acid that can dissolve either of its components. Both differ from the true James's powder, in which I have found a protoxide of antimony, to which it owes its efficacy, whilst the antimonial powder contains antimonious acid, which is inert.

Medical properties and uses. - Antimonial powder is intended to operate as a diaphoretic, alterative, emetic, or purgative, according to the extent of the dose, and the state or habit of the patient to whom it is administered. It is the preparation of antimony which was, until lately, most commonly employed in the commencement of fevers, and in inflammatory affections; being generally given with a view to its diaphoretic effect: and it is true that when a copious perspiration is early induced, after having previously evacuated the stomach and bowels, fevers of the most threatening aspect are often cut short by it: but too often it fails in producing this result, and, according to Dr. Elliotson's experiments, 100 grains have been given without producing any effect. That the specimens, which I have employed, have sometimes produced the intention expected, I can bear testimony: but justice obliges me to acknowledge that I have been as often disappointed; and every object for which antimonial powder can be prescribed is more certainly obtained from the employment of small doses of tartar emetic.

Supposing that it is properly prepared, and acts like true James's powder, I should say, that those labouring under inflammatory diseases, who can bear considerable discharges by stool, experience the most benefit from the use of the antimonial powder, particularly when venesection has been previously employed. In acute rheumatism it is advantageously given, combined with camphor, calomel, and opium; and with calomel and guaia-cum in several cutaneous affections. As it is insoluble in water, it is given either in the form of a powder, or made up in pills. The dose is from grs. iij. to Эj., repeated every fourth hour, diluting freely in the intervals, until its diaphoretic effects are obtained.

1 Phil. Mag. xi. 110.

2 Phil. Trans, lxxxi. 317. Another analysis of this powder has been published lately by M. Pully, an Italian chymist, who gives the following as its constituents : seven parts of protoxide of antimony, four of phosphate of lime, four and a half of sulphate of potassa, and three and a half of potassa, holding in solution protoxide of antimony. Annates de Chimie, lv. 74. Thomson's Chemistry, 4th ed. iii. 315.