Having considered the simpler substances, those composed of pure elemental forms, and those resembling them--the meteors--we turn to the perfect compounds, those which have assumed substantial forms, as metals, stones, etc. Our author retains the Aristotelian classification--earthy, and those of other origin, as beasts, roots, and trees. Earths may be metals or fossils; metals being defined as hard bodies, generated in the earth or in its veins, which can be beaten out by a hammer, and softened or liquefied by heat; while fossils include all other inanimate objects. A large number of extracts have been made from this part of the subject, because the book gives the position of positive, as distinguished from speculative, Alchemy at the time. It is the Editor's desire to show that at this period there was a system of theory based on the practical knowledge of the day. Chemistry took its rise as a science about four hundred years before our era. In the fragments of two of the four books of Democritus we have probably the earliest treatise on chemical matters we are ever likely to get hold of. Whether it is the work of Democritus or of a much later writer is uncertain. But merely taking it as a representative work of the early stage of chemistry, we remark that the receipts are practicable, and some of them, little modified, are in use to-day in goldsmith's shops. The fragments remaining to us are on the manufacture of gold and silver, and one receipt for dyeing purple. In this state of the science the collection of facts is the chief point, and no purely chemical theory seems to have been formed. Tradition, confirmed by the latest researches, associates this stage with Egypt. The second stage in the history of Chemistry--the birth of Alchemy in the Western World--occurred when the Egyptian practical receipts, the neo-Greek philosophies, and the Chinese dreams of an "elixir vitae" were fused into one by the Arab and Syriac writers. Its period of activity ranges from the seventh to the tenth centuries. Little is really known about it, or can be, until the Arabic texts, which are abundant in Europe, are translated and classified both from the scholar's and the chemist's standpoint. Many works were translated into Latin about the end of the tenth century, such as the spurious fourth book of the _Meteorics of Aristotle_, the treatises of the _Turta Philosophorum_, _Artis Auriferae_, etc., which formed the starting-point of European speculation. The theoretical chemistry of our author is derived from them. The third stage of chemistry begins with the fourteenth and ends with the sixteenth century. It is characterized by an immense growth of theory, a fertile imagination, and untiring industry. It reached its height in England about 1440, and is represented by the reputed works of Lully (vixit circ. 1300), which first appeared about this date. In this period practical alchemy is on its trial.