The qualities of all things are to be found in their spirit rather than in the things themselves. Ancient physicians, knowing this, tried to extract the essence from certain things by grinding, by burning, or by washing them a great number of times. By doing this they were able to bring out the spirit of the object, and that spirit became a thousand times more powerful than the object itself. Those who are acquainted with alchemy know how to bring out the living part hidden within every substance, every object, and even to some extent their essence; and when this essence is extracted, then all the benefit that can be derived from that object is derived.