10. The mode of projecting is this: Take of the fermented sulphur one part, and project it upon ten parts of mercury, heated in a crucible, and you will have a perfect metal; if its colour is not sufficiently deep, fuse it again, and add more fermented sulphur, and thus it will acquire colour. If it becomes frangible, add a sufficient quantity of mercury and it will be perfect. Thus, friend, you have a description of the universal medicine, not only for curing diseases and prolonging life, but also for transmuting all metals into gold. Give therefore thanks to Almighty God, who, taking pity on human calamities, has at last revealed this inestimable treasure, and made it known for the common benefit of all.[19] [19] Mangeti Bibliothecæ Chemicæ Præfatio. Such is the formula (slightly abridged) of Carolus Musitanus, by which the philosopher’s stone, according to him, may be formed. Compared with the formulas of most of the alchymists, it is sufficiently plain. What the _sublimed mercury_ is does not appear; from the process described we should be apt to consider it as _corrosive sublimate_; on that supposition, the sal sapientum formed in No. 5, would be calomel: the only objection to this supposition is the process described in No. 5; for calomel is not soluble in alcohol. The philosopher’s stone prepared by this elaborate process could hardly have been any thing else than an _amalgam of gold_; it could not have contained chloride of gold, because such a preparation, instead of acting medicinally, would have proved a most virulent poison. There is no doubt that amalgam of gold, if projected into melted lead or tin, and afterwards cupellated, would leave a portion of gold--all the gold of course that existed previously in the amalgam. It might therefore have been employed by impostors to persuade the ignorant that it was really the philosopher’s stone; but the alchymists who prepared the amalgam could not be ignorant that it contained gold. There is another process given in the same preface of a very different nature, but too long to be transcribed here, and the nature of the process is not sufficiently intelligible to render an account of it of much consequence.[20] [20] Whoever wishes to enter more particularly into the processes for making the philosopher’s stone contrived by the alchymists, will find a good deal of information on the subject in Stahl’s Fundamenta Chemiæ, vol. i. p. 219, in his chapter _De lapide philosophorum_: and Junker’s Conspectus Chemiæ, vol. i. p. 604, in his tabula 28, _De transmutatione metallorum universali_: and tabula 29, _De transmutatione metallorum particulari_.