Page:De re metallica (1912).djvu/88

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Another occupies a large extent of space in length and width; therefore I usually call it vena cumulata,for it is nothing else than an accumulation of some certain kind of mineral, as I have described in the book

    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 sleinendegange, 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 oredeposits, 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:

    1. Openings in the earth (canales) were formed by the erosion of subterranean waters.
    2. These ground waters were due (a) to the infiltration of the surface waters, rain, river, and sea water; (6) to the condensation of steam (halitus) arising from the penetration of the surface waters to greater depths, the production of this halitus being due to subterranean heat, which in his view was in turn due in the main to burning bitumen (a comprehensive genera which embraced coal).
    3. The filling of these canales is composed of earth,solidified juices,stone,metals, and compounds,all deposited from water and juices circulating in the canales. (See also note 4, page i).
    Earth comprises clay, mud, ochre, marl, and peculiar earths generally. The origin of these earths was from rocks, due to erosion, transportation, and deposition by water. Solidified juices (sued concreti) comprised salt, soda, vitriol, bitumen, etc., being generally those substances which he conceived were soluble in and deposited from water. Stones comprised precious, semi-precious, and unusual stones, such as quartz, fluor-spar, etc., as distinguished from country rock; the origin of these he attributed in minor proportion to transportation of fragments of rock, but in the main to deposits from ordinary mineral juice and from "stone juice(succuslapidescens). Metals comprised the seven traditional metals; the compounds comprised the metallic minerals; and both were due to deposition from juices, the compounds being due to a mixture of juices. The juices play the most important part in Agricola’s theory. Each substance had its own particular juice, and in his theory every substance had a material and an efficient cause, the first being the juice, the second being heat or cold. Owing to the latter the juices fell into two categories those solidified by heat (i.e., by evaporation, such as salt), and those solidified by cold, (i.e, because metals melt and flow by heat, therefore their solidification was due to cold, and the juice underwent similar treatment). As to the origin of these juices, some were generated by the solution of their own particular substance, but in the