[Pg 43][1] Modern nomenclature in the description of ore-deposits is so impregnated with modern views of their origin, that we have considered it desirable in many instances to adopt the Latin terms used by the author, for we believe this method will allow the reader greater freedom of judgment as to the author's views. The Latin names retained are usually expressive even to the non-Latin student. In a general way, a vena profunda is a fissure vein, a vena dilatata is a bedded deposit, and a vena cumulata an impregnation, or a replacement or a stockwerk. The canales, as will appear from the following footnote, were ore channels. "The seams of the rocks" (commissurae saxorum) are very puzzling. The author states, as appears in the following note, that they are of two kinds,—contemporaneous with the formation of the rocks, and also of the nature of veinlets. However, as to their supposed relation to the strike of veins, we can offer no explanation. There are passages in this chapter where if the word "ore-shoot" were introduced for "seams in the rocks" the text would be intelligible. That is, it is possible to conceive the view that the determination of whether an east-west vein ran east or ran west was dependent on the dip of the ore-shoot along the strike. This view, however, is utterly impossible to reconcile with the description and illustration of commissurae saxorum given on page [54], where they are defined as the finest stringers. The following passage from the Nützliche Bergbüchlin (see [Appendix]), reads very much as though the dip of ore-shoots was understood at this time in relation to the direction of veins. "Every vein (gang) has two (outcrops) ausgehen, one of the ausgehen is toward daylight along the whole length of the vein, which is called the ausgehen of the whole vein. The other ausgehen is contrary to or toward the strike (streichen) of the vein, according to its rock (gestein), that is called the gesteins ausgehen; for instance, every vein that has its strike from east to west has its gesteins ausgehen to the east, and vice-versa."
Agricola's classification of ore-deposits, after the general distinction between alluvial and in situ deposits, is based entirely upon form, as will be seen in the quotation below relating to the origin of canales. The German equivalents in the Glossary are as follows:—
| Fissure vein (vena profunda) | Gang. |
| Bedded deposit (vena dilatata) | Schwebender gang oder fletze. |
| Stockwerk or impregnation (vena cumulata) | Geschute oder stock. |
| Stringer (fibra) | Klufft. |
| Seams or joints (commissurae saxorum) | Absetzen des gesteins. |
It is interesting to note that in De Natura Fossilium he describes coal and salt, and later in De Re Metallica he describes the Mannsfeld copper schists, as all being venae dilatatae. This nomenclature and classification is not original with Agricola. Pliny (XXXIII, 21) uses the term vena with no explanations, and while Agricola coined the Latin terms for various kinds of veins, they are his transliteration of German terms already in use. The Nützliche Bergbüchlin gives this same classification.
Historical Note on the Theory of Ore Deposits. Prior to Agricola there were three schools of explanation of the phenomena of ore deposits, the orthodox followers of the Genesis, the Greek Philosophers, and the Alchemists. The geology of the Genesis—the contemporaneous formation of everything—needs no comment other than that for anyone to have proposed an alternative to the dogma of the orthodox during the Middle Ages, required much [Pg 44]independence of mind. Of the Greek views—which are meagre enough—that of the Peripatetics greatly dominated thought on natural phenomena down to the 17th 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 fundamental 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 properties 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 VII.) 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 (XXXIII, 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 (13th (?) 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 Bergbüchlin (about 1520, 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 [Pg 46]united through the effect of the planets and made into ore. Certain others hold that metal is not formed from quicksilver, because in many places metallic ore is found and no quicksilver. But instead of quicksilver they maintain a damp and cold and slimy material is set up on all sulphur which is drawn out from the earth, like your perspiration, and from that mixed with sulphur all metals are formed. Now each of these opinions is correct according to a good understanding and right interpretation; the ore or metal is formed from the fattiness of the earth as the material of the first degree (primary element), also the vapours or braden on the one part and the materials on the other part, both of which are called quicksilver. Likewise in the mingling or union of the quicksilver and the sulphur in the ore, the sulphur is counted the male and quicksilver the female, as in the bearing or conception of a child. Also the sulphur is a special worker in ore or metal.
"The second chapter or part deals with the general capacity of the mountain. Although the influence of the heavens and the fitness of the material are necessary to the formation of ore or metal, yet these are not enough thereto. But there must be adaptability of the natural vessel in which the ore is formed, such are the veins, namely steinendegange, flachgange, schargange, creutzgange, or as these may be termed in provincial names. Also the mineral force must have easy access to the natural vessel such as through the kluffte (stringers), namely hengkluft, querklufte, flachekluffte, creutzklufft, and other occasional flotzwerk, according to their various local names. Also there must be a suitable place in the mountain which the veins and stringers can traverse."
Agricola's Views on the Origin of Ore Deposits. Agricola rejected absolutely the Biblical view which, he says, was the opinion of the vulgar; further, he repudiates the alchemistic and astrological view with great vigour. There can be no doubt, however, that he was greatly influenced by the Peripatetic philosophy. He accepted absolutely the four elements—earth, fire, water, and air, and their "binary" properties, and the theory that every substance had a material cause operated upon by an efficient force. Beyond this he did not go, and a large portion of De Ortu et Causis is devoted to disproof of the origin of metals and stones from the Peripatetic "exhalations."
No one should conclude that Agricola's theories are set out with the clarity of Darwin or Lyell. However, the matter is of such importance in the history of the theory of ore-deposits, and has been either so ignored or so coloured by the preconceptions of narrators, that we consider it justifiable to devote the space necessary to a reproduction of his own statements in De Ortu et Causis and other works. Before doing so we believe it will be of service to readers to summarize these views, and in giving quotations from the Author's other works, to group them under special headings, following the outline of his theory given below. His theory was:—