To begin, "The Mirror of Alchemy", composed by the famous Friar, Roger Bacon, sometime fellow of Martin College and Brasen-nase College in Oxenforde.
Of the Definitions of Alchemy
In many ancient Books there are found many definitions of this Art, the intentions whereof we must consider in this Chapter. For Hermes said of this Science: Alchemy is a Corporal Science simply composed of one and by one, naturally conjoining things more precious, by knowledge and effect, and converting them by a natural commixtion into a better kind. A certain other said: Alchemy is a Science, teaching how to transform any kind of metal into another: and that by a proper medicine, as it appeared by many Philosophers' Books. Alchemy therefore is a science teaching how to make and compound a certain medicine, which is called Elixir, the which when it is cast upon metals or imperfect bodies, does fully perfect them in the very projection.
