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

discussing, namely, what is the first and proximate matter of metals, what is their efficient cause, how they differ among themselves, whether by some substantial form or only by accidentals, what affinities they possess, whether one can be transformed into another, and how they ought to be brought to the highest perfection. All these things, and many others of this kind, while they either investigate them or assert with great constancy and authority that they have long since found them, bring so much light and knowledge that I for one would not reluctantly doubt whether even Aristotle or Theophrastus could have provided as much. This significant addition to philosophy should not, therefore, be neglected or despised by students, however much it must be begged here and there from a barbaric class of writers, and collected like gold from dung. There is also another reason, not small, why you might wish to know them. For after the fame of this art once filled the world, many scoundrels have wandered everywhere who profess it, while knowing nothing less, and they plunder simpletons, greedy for both wealth and an admirable art, by feeding them with empty hope, whether by theft or fraud. No one will detect the wickedness, fraud, and deceptions of such men more quickly, nor refute them more effectively, than he who has penetrated into the inner chambers of this art. For this art, without the knowledge of philosophy (which they cannot feign), falls to no one, and it hands down tests of true gold and silver so certain and effective that no fraud, however clever or hidden, can be applied to them that it does not detect and utterly destroy, which is also of the greatest interest to the Republic. Since, therefore, these authors enrich philosophy and expose the forgers who are harmful to the Republic, they were worthy of knowledge, even if the art itself were nothing in itself. Although I see no reason why we should consider it not to be true. For it is asserted probably by men most exercised in philosophy. And certain artisans, without any manifest cause for lying, have confirmed by all holy things, even in published books, that they have found it. To which the affections of their souls bear witness, exulting in themselves with joy at the discovered art, bursting forth so vehemently that it is incredible that such a simulation could be feigned by any art. It also has testimonies of history. For Suidas, an author not at all to be despised, writes that the Egyptians, relying on the wealth from this art, studied to make revolutions and were restrained by Diocletian. But I will recite his words:

Chemistry original: "Χημεία" (he says) is the making of gold and silver, whose books Diocletian searched out and burned, because of the innovations made by the Egyptians against Diocletian. He treated them harshly and murderously. At that time, indeed, he searched out and burned the books written by the ancients about the chemistry of gold and silver, so that wealth might no longer accrue to the Egyptians from such an art, nor that they, relying on an abundance of money, should subsequently rise up against the Romans.