Like all the preparations of antimony, emetic tartar is active in proportion to its solubility; and the scale of solubility extends from three times its weight in boiling water, and fifteen at 60°, to forty and eighty in the same circumstances. In the former case the salt was peculiarly pure. Were we to follow every refinement adopted at different times by different chemists in preparing the emetic tartar, we might fill a volume. The quantity of water need not be more than will dissolve the tar-trite of antimony when formed, and the time of boiling no longer than is necessary to the combination. Some time longer than that required for the solution of the crystals of tartar is requisite, though not a considerable period, or longer than a quarter of an hour. The excellence of the preparation consists in the size, the shape, and the length of the crystals with which the solubility of the salt is connected. The proper form of its crystals is that of triangular pyramids, or in octoedrons more elongated than those of alum. In general they are too short, and, if carefully examined, have a portion of uncombined oxide adhering to them. The impediments to a proper and regular crystallization are, first, the silica, discovered by Vauquelin; and he tells us, that if the salt be evaporated to dryness, this is separated in an insoluble state: the salt may then be crystallized without further impediment from it. Another cause of imperfect crystallization is a portion of uncombined tartrite of potash. For this reason the Dublin college order the fluid to be filtered, and the remaining salts to be thrown away; but the end may be as well obtained by increasing the proportion of the oxide. Thenard very properly advises two crystallizations; and this, we think, should always be done. His object is to separate the tartrite of lime, which crystallizes in silky needles. According to this author, the emetic tartar consists of thirty-eight parts of oxide of antimony; thirty-four of tartarous acid; sixteen of potash; and twelve of water, including loss. We observe a German chemist, in Tromsdorf's Journal, directs the solution, previous to crystallization, to be exposed for fifteen days to a strong light, which seems only to facilitate the formation of the crystals.

The antimonial wines of the Dispensatories are now only solutions of tartarized antimony in wine, or in a small proportion of water added to wine. These forms are convenient for division, and require no comment. The antimonial wine of the former edition of the London Dispensatory was an unequal medicine, as the glass of antimony infused in wine could be only dissolved by its tartar, which, in different wines, is in unequal proportions. Oxalates and acetites of antimony have been prepared; but their medical qualities are little known, or, if known, do not apparently differ from those of emetic tartar. The fluoric and boracic acids act on the oxides of antimony; but they have not yet been noticed by the medical chemist.

The decomposition of the antimonial salts, particularly the tartrites, is not so easy as some chemists have supposed. From a superficial view it would appear that all acids and alkalis would occasion a separation of their component parts. Authors, however, who have been full in their cautions on this subject, have not reflected that the emetic tartar, is a triple salt, and that a minute portion of acid will affect only the tartrite of potash, while the antimonial neutral will not be altered in its medical properties, though, in a chemical view, the salt is not the same. The mineral acids will, indeed, decompose the neutral and the metallic salt, and some alkalis will certainly affect the latter. This must be particularly attended to if the preparations of foreign pharmacopoeias are employed, as in many of their tinctures an alkaline salt is added. In the decoctions of our pharmacopoeias it was sometimes an ingredient; but, we believe, the decoction of bardana was the last instance, and it is now disused. The peculiar powers of the emetic tartar are greatly weakened by bitters, and particularly the bark. A modern author of credit, Tromsdorf, remarks, that a scruple of emetic tartar, with an ounce of Peruvian bark in decoction, is not usually emetic.

Here, perhaps, we might stop; but various preparations, and various titles of well known preparations, are to be found in authors, of which a medical dictionary should give some account. We have compacted what is useful in a continued narrative, but shall now insert a table of the preparations of antimony, in which they are arranged from the nature of the product, for which we are indebted to Dr. Duncan; and then add some of the preparations of foreign authors, which have been at least highly commended, though not usually employed in these kingdoms, in the order of the table.

Antimony has been exhibited:

I. In its metallic state.

a. Antimonium: regulus antimonii.

b. Alloyed.

1. With iron: regulus antimonii martialis.

2. With tin: regulus antimonii jovialis.

3. With tin and copper: regulus metallorum.

c. Combined with sulphur.

1. Sulphurerum antimon. Ed. Antimonium Lond. Stibium, Dublin.

2. Regulus antimon. medicinalis (Maet.). Fe-brifugum Craanii.

d. Combined with sulphuret of potash. - Hepar antimonii.

II. Oxidised.

a. In a smaller degree.

1. Calx antimonii per se cinis antimonii.

2. Flores antimonii argentini.

3. Pulvis algarotti.

4. Vitrum antimonii - combined with wax, vi-truni antimonii ceratum.

b. Combined with a little sulphur, crocus antimonii: crocus metallorum.

c. --------------------sulphuretted hydrogen, sulphur auratum antimonii.

d. --------------------hydroguretted sulphur, kermes mineral.

e .--------------------muriatic acid, butyrum antimonii.

f. --------------tartarous acid and potash, tartarus emeticus: dissolved in wine, vinum antimoniale. g. --------------------phosphoric acid and phosphat of lime, James's powder. h. Oxidised in a greater degree, antimonium calcinatum, London. In following this table we must first remark, that, besides the alloys of iron, tin, or tin and copper, we find a regulus saiurninus in Stahl; r. -venereus in Lemery; an alloy of the regulus martialis with copper in Stahl, under the fanciful name of retevulcani; regulus lunaris, and. Solaris, in Lemery, viz. antimony united with silver and gold. The regulus metallorum is usually styled the electrum majus; the regulus jovialis, electrum minus. We need scarcely add, that all these preparations are useless. Thefebrifuge of Craanen excited general attentionon the continent; and it has particularly engaged the attention of Stahl, of Hoffman, of Dieterich, and Vogel. It was supposed to be a specific in intermittents; to be of service in gout, in dropsy, and malignant fevers. In the long list of its qualities, however, which we have carefully perused, we perceive nothing but what other antimonials will perform; and, if useful in low fevers, the advantage must have arisen from the bark with which it was sometimes joined. It was prepared in a variety of ways: and the great object seems to have been its red colour, from which it was called rubinus antimonii, and magnesia opalina.