Georg Ernst Stahl quotes:

Chymia, or Alchemy and Spagyrism, is the art of resolving compound bodies into their principles and of combining these again.

Briefly, in the act of composition, as an instrument there intervenes and is most potent, fire, flaming, fervid, hot; but in the very substance of the compound there intervenes, as an ingredient, as it is commonly called, as a material principle and as a constituent of the whole compound the material and principle of fire, not fire itself. This I was the first to call phlogiston.