He makes known the method of dissolving most of the metals in muriatic acid, and the resulting chlorides, which he denominates oils of the respective metals, constitute in his opinion valuable medicines. He mentions particularly the chloride of gold, and from the mode of preparing it, the solution must have been strong. Yet he recommends it as an internal medicine, which he says may be taken with safety, and is a sovereign remedy in old ulcers of the mouth, tongue, and throat, arising from the French pox, leprosy, scorbute, &c. Thus we see the use of gold as a remedy for the venereal disease did not originate with M. Chretiens, of Montpelier. This chloride of gold is so violent a poison that it is remarkable that Glauber does not specify the dose that patients labouring under the diseases for which he recommends it ought to take.--The sesqui-chloride of iron he recommends as a most excellent application to ill-conditioned ulcers and cancers. We see from this that the use of iron in cancers, lately recommended, is not so new a remedy as has been supposed. He mentions the violent action of chloride of mercury (obviously corrosive sublimate), and says that he saw a woman suddenly killed by it, being administered internally by a surgeon. Butter of antimony he first recognised as nothing else than a combination of chlorine and antimony; before his time it had been always supposed to contain mercury. He describes the method of obtaining sulphuric acid by distilling sulphate of iron; gives an account of the mode of obtaining sulphate of iron and sulphate of copper, in crystals: the method of obtaining nitric acid from nitre by means of alum, was much improved by him. He gives a particular detail of the way of obtaining fulminating gold. This fulminating gold he says is of little use in medicine; but he gives a method of preparing from it a red tincture of gold, which he considers as one of the most useful and efficacious of all medicines: this tincture is nothing else than chloride of gold. It would take up too much space to attempt an analysis of all the curious facts and preparations described in this treatise on philosophical furnaces; but it will repay the perusal of any person who will take the trouble to look into it. All the different pharmacopœias of the seventeenth century borrowed from it largely. The third part of this treatise is peculiarly interesting. It will be seen that Glauber had already thought of the peculiar efficacy of applying solutions of sulphur, &c. to the skin, and had anticipated the various vapour and gaseous baths which have been introduced in Vienna and other places, during the course of the present century, and considered as new, and as constituting an important era in the healing art. In the fourth part he not only treats of the docimastic processes, so well described by Agricola and Erckern, but gives us the method of making glass, and of imitating the precious stones by means of coloured glasses. The