Philosophy which treats of the origins, causes and natures of things, Illustrious Prince, has been divided into many parts and must explain very difficult things. For example, it expounds the divinity and reality of God, the heavens and stars, the elements, causes, interrelationships between these things, changes in the atmosphere, as well as living and subterranean bodies and their origins. The concept of God has aroused all nations and peoples but the Jews, Egyptians and Greeks were the first to consider the nature of God. The Chalddeans after long observation and the Greeks after careful study came to know the stars and learned to measure the heavens. The Greeks, more than any other people, studied the elements, their causes, and the interrelationship between natural bodies. Aristotle considered the movements and changes in the atmosphere as well as the species, nature and origin of living matter. Theophrastus has discussed the causes and natures of original life. But the subject of subterranean things in which we are most interested has never been properly treated.
We have already considered the origins and causes of subterranean things. 1 Some of these flow from the earth while others are dug out of it. We have discussed the nature of the former in a previous treatise. 2 In the next ten books we will discuss the distinctive features, physical characters and useful properties of those things which are dug up. The first of these books considers the distinctive features and discusses the origins of all mineral matter; the . . .