First I will speak of the veins, which, in depth, width, and length, differ very much one from another. Those of one variety descend from the surface of the earth to its lowest depths, which on account of this characteristic, I am accustomed to call " venae profundae."
much independence of mind. Of the Greek views which are meagre enough that of the Peripatetics greatly dominated thought on natural phenomena down to the iyth century. Aristotle's views may be summarized : The elements are earth, water, air, and fire ; they are transmutable and never found pure, and are endowed with certain funda- mental properties which acted as an "efficient" force upon the material cause the elements. These properties were dryness and dampness and heat and cold, the latter being active, the former passive. Further, the elements were possessed of weight and lightness, for instance earth was absolutely heavy, fire absolutely light. The active and passive proper- ties existed in binary combinations, one of which is characteristic, i.e., " earth " is cold and dry, water damp and cold, fire hot and dry, air hot and wet ; transmutation took place, for instance, by removing the cold from water, when air resulted (really steam), and by removing the dampness from water, when " earth " resulted (really any dissolved substance). The transmutation of the elements in the earth (meaning the globe) produces two " exhalations," the one fiery (probably meaning gases), the other damp (probably meaning steam). The former produces stones, the latter the metals. Theophrastus (On Stones, I to vn.) elaborates the views of Aristotle on the origin of stones, metals, etc. : " Of things " formed in the earth some have their origin from water, others from earth. Water is the " basis of metals, silver, gold, and the rest ; ' earth ' of stones, as well the more precious " as the common. . . . All these are formed by solidification of matter pure and " equal in its constituent parts, which has been brought together in that state by mere " afflux or by means of some kind of percolation, or separated. . . . The solidification " is in some of these substances due to heat and in others to cold." (Based on Hill's Trans., pp. 3-11). That is, the metals inasmuch as they become liquid when heated must be in a large part water, and, like water, they solidify with cold. Therefore, the " metals are cold and damp." Stones, on the other hand, solidify with heat and do not liquefy, therefore, they are " dry and hot " and partake largely of " earth." This " earth" was something indefinite, but purer and more pristine than common clay. In discussing the ancient beliefs with regard to the origin of deposits, we must not overlook the import of the use of the word "vein" (vena) by various ancient authors including Pliny (xxxm, 21), although he offers no explanation of the term. During the Middle Ages there arose the horde of Alchemists and Astrologers, a review of the development of whose muddled views is but barren reading. In the main they held more or less to the Peripatetic view, with additions of their own. Geber (i3th (?) century, see Appendix B) propounded the conception that all metals were composed of varying proportions of " spiritual " sulphur and quicksilver, and to these Albertus Magnus added salt.' The Astrologers contributed the idea that the immediate cause of the metals were the various planets. The only work devoted to description of ore-deposits prior to Agricola was the Bergbiichlin (about 1,520, see Appendix B), and this little book exhibits the absolute apogee of muddled thought derived from the Peripatetics, the Alchemists, and the Astrologers. We believe it is of interest to reproduce the following statement, if for no other reason than to indicate the great advance in thought shown by Agricola. " The first chapter or first part ; on the common origin of ore, whether silver, gold, " tin, copper, iron, or lead ore, in which they all appear together, and are called by the common " name of metallic ore. It must be noticed that for the washing or smelting of metallic ore, " there must be the one who works and the thing that is worked upon, or the material upon " which the work is expended. The general worker (efficient force) on the ore and on all " things that are born, is the heavens, its movement, its light and influences, as the " philosophers say. The influence of the heavens is multiplied by the movement of the "' firmaments and the movements of the seven planets. Therefore, every metallic ore ' receives a special influence from its own particular planet, due to the properties of the ' planet and of the ore, also due to properties of heat, cold, dampness, and dryness. Thus ' gold is of the Sun or its influence, silver of the Moon, tin of Jupiter, copper of Venus, iron ' of Mars, lead of Saturn, and quicksilver of Mercury. Therefore, metals are often called by ' these names by hermits and other philosophers. Thus gold is called the Sun, in Latin Sol, ' silver is called the Moon, in Latin Luna, as is clearly stated in the special chapters on each ' metal. Thus briefly have we spoken of the ' common worker ' of metal and ore. But the ' thing worked upon, or the common material of all metals, according to the opinion of ' the learned, is sulphur and quicksilver, which through the movement and influence of the ' heavens must have become united and hardened into one metallic body or one ore. ' Certain others hold that through the movement and the influence of the heavens, vapours ' or braden, called mineral exhalations, are drawn up from the depths of the earth, from " sulphur and quicksilver, and the rising fumes pass into the veins and stringers and are
