Alchemiae Gebri Arabis philosophi solertissimi, libri, cum reliquis, ut versa pagella indicabit

commentary, which we have composed for the purpose of explaining it. Therefore, by right, this one precedes that one, since through this book I seek to investigate the knowledge of the perfecting thing.

Since this science treats of the imperfect bodies of minerals, in as much as it is fitting to perfect them, we first considered two things regarding these: namely, Imperfection and Perfection. Upon these two we found our intention. We are composing this book about the things that perfect and corrupt, according to what we have investigated through our experience, because opposites placed next to each other shine more brightly. The thing that perfects in minerals is the substance of argentum vivum quick-silver/mercury and sulphur mixed proportionately, thickened and fixed through long and temperate decoction slow heating in the bowels of clean earth, with the preservation of its radical moisture, not corrupting, but produced into a solid substance fusible with due ignition and extensible under the hammer. Through the definition of the nature of this perfecting thing, we can more easily arrive at the knowledge of the corrupting thing. And it is that which is to be understood from the contrary sense, namely, an impure substance of quick-silver and sulphur, mixed without due proportion, or less decocted in the bowels of unclean earth, neither correctly thickened, nor fixed, having moisture that is combustible and corrupting, and of a rare and porous substance: or having fusion without due ignition, or none at all, nor suffering the hammer sufficiently. I found the first definition embedded in these two bodies, namely, in Sol Gold/Sun and Luna Silver/Moon, according to the