"Now, according to the ancient Sages there are two principles of things, and more particularly of metals, namely, Sulphur and Mercury; according to the Moderns there are three: Salt, Sulphur, and Mercury, and the source of these principles are the elements; of which it therefore behoves us to speak first. Be it known to the students of this art that there are four elements, and that each has at its centre another element which makes it what it is. These are the four pillars of the world. They were in the beginning evolved and moulded out of chaos by the hand of the Creator; and it is their contrary action which keeps up the harmony and equilibrium of the mundane machinery; it is they which, through the virtue of celestial influences, produce all things above and beneath the earth."