FOOTNOTES:
[Pg 25] [1] Xenophon. Essay on the Revenues of Athens, IV., 14.
"But we cannot but feel surprised that the State, when it sees many private individuals enriching themselves from its resources, does not imitate their proceedings; for we heard long ago, indeed, at least such of us as attended to these matters, that Nicias the son of Niceratus kept a thousand men employed in the silver mines, whom he let on hire to Sosias of Thrace on condition that he should give him for each an obolus a day, free of all charges; and this number he always supplied undiminished." (See also [Note 6]). An obolus a day each, would be about 23 oz. Troy of silver per day for the whole number. In modern value this would, of course, be but about 50s. per day, but in purchasing power the value would probably be 100 to 1 (see Note on p. [28]). Nicias was estimated to have a fortune of 100 talents—about 83,700 Troy ounces of silver, and was one of the wealthiest of the Athenians. (Plutarch, Life of Nicias).
[Pg 26][2] Xenophon. Oeconomicus XII., 20. "'I approve,' said Ischomachus, 'of the barbarian's answer to the King who found a good horse, and, wishing to fatten it as soon as possible, asked a man with a good reputation for horsemanship what would do it?' The man's reply was: 'Its master's eye.'"
[3] Praefectus Metallorum. In Saxony this official was styled the Berghauptmann. For further information see page [94] and note on page [78].
[4] This statement is either based upon Apollodorus, whom Agricola does not mention among his authorities, or on Strabo, whom he does so include. The former in his work on Mythology makes such a statement, for which Strabo (XIV., 5, 28) takes him to task as follows: "With this vain intention they collected the stories related by the Scepsian [Pg 27](Demetrius), and taken from Callisthenes and other writers, who did not clear them from false notions respecting the Halizones; for example, that the wealth of Tantalus and of the Pelopidae was derived, it is said, from the mines about Phrygia and Sipylus; that of Cadmus from the mines of Thrace and Mount Pangaeum; that of Priam from the gold mines of Astyra, near Abydos (of which at present there are small remains, yet there is a large quantity of matter ejected, and the excavations are proofs of former workings); that of Midas from the mines about Mount Bermium; that of Gyges, Alyattes, and Croesus, from the mines in Lydia and the small deserted city between Atarneus and Pergamum, where are the sites of exhausted mines." (Hamilton's Trans., Vol. III., p. 66).
In adopting this view, Agricola apparently applied a wonderful realism to some Greek mythology—for instance, in the legend of Midas, which tells of that king being rewarded by the god Dionysus, who granted his request that all he touched might turn to gold; but the inconvenience of the gift drove him to pray for relief, which he obtained by bathing in the Pactolus, the sands of which thereupon became highly auriferous. Priam was, of course, King of Troy, but Homer does not exhibit him as a mine-owner. Gyges, Alyattes, and Croesus were successively Kings of Lydia, from 687 to 546 B.C., and were no doubt possessed of great treasure in gold. Some few years ago we had occasion to inquire into extensive old workings locally reputed to be Croesus' mines, at a place some distance north of Smyrna, which would correspond very closely to the locality here mentioned.
[5] There can be no doubt that the Carthaginians worked the mines of Spain on an extensive scale for a very long period anterior to their conquest by the Romans, but whether the mines were worked by the Government or not we are unable to find any evidence.
[6] The silver mines of Mt. Laurion formed the economic mainstay of Athens for the three centuries during which the State had the ascendency in Greece, and there can be no doubt that the dominance of Athens and its position as a sea-power were directly due to the revenues from the mines. The first working of the mines is shrouded in mystery. The scarcity of silver in the time of Solon (638-598 B.C.) would not indicate any very considerable output at that time. According to Xenophon (Essay on Revenue of Athens, IV., 2), written about 355 B.C., "they were wrought in very ancient times." The first definite discussion of the mines in Greek record begins about 500 B.C., for about that time the royalties began to figure in the Athenian Budget (Aristotle, Constitution of Athens, 47). There can be no doubt that the mines reached great prosperity prior to the Persian invasion. In the year 484 B.C. the mines returned 100 Talents (about 83,700 oz. Troy) to the Treasury, and this, on the advice of Themistocles, was devoted to the construction of the fleet which conquered the Persians at Salamis (480 B.C.). The mines were much interfered with by the Spartan invasions from 431 to 425 B.C., and again by their occupation in 413 B.C.; and by 355 B.C., when Xenophon wrote the "Revenues," exploitation had fallen to a low ebb, for which he proposes the remedies noted by Agricola on p. [28]. By the end of the 4th Century, B.C., the mines had again reached considerable prosperity, as is evidenced by Demosthenes' orations against Pantaenetus and against Phaenippus, and by Lycurgus' prosecution of Diphilos for robbing the supporting pillars. The domination of the Macedonians under Philip and Alexander at the end of the 4th and beginning of the 3rd Centuries B.C., however, so flooded Greece with money from the mines of Thrace, that this probably interfered with Laurion, at this time, in any event, began the decadence of these mines. Synchronous also was the decadence of Athens, and, but for fitful displays, the State was not able to maintain even its own independence, not to mention its position as a dominant State. Finally, Strabo, writing about 30 B.C. gives the epitaph of every mining district—reworking the dumps. He says (IX., 1, 23): "The silver mines in Attica were at first of importance, but [Pg 28]are now exhausted. The workmen, when the mines yielded a bad return to their labour, committed to the furnace the old refuse and scoria, and hence obtained very pure silver, for the former workmen had carried on the process in the furnace unskilfully."
Since 1860, the mines have been worked with some success by a French Company, thus carrying the mining history of this district over a period of twenty-seven centuries. The most excellent of many memoirs upon the mines at Laurion, not only for its critical, historical, and archæological value, but also because of its author's great insight into mining and metallurgy, is that of Edouard Ardaillon (Les Mines du Laurion dans l'Antiquité, Paris, 1897). We have relied considerably upon this careful study for the following notes, and would refer others to it for a short bibliography on the subject. We would mention in passing that Augustus Boeckh's "Silver Mines of Laurion," which is incorporated with his "Public Economy of Athens" (English Translation by Lewis, London, 1842) has been too much relied upon by English students. It is no doubt the product of one acquainted with written history, but without any special knowledge of the industry and it is based on no antiquarian research. The Mt. Laurion mining district is located near the southern end of the Attic Peninsula. The deposits are silver-lead, and they occur along the contact between approximately horizontal limestones and slates. There are two principal beds of each, thus forming three principal contacts. The most metalliferous of these contacts are those at the base of the slates, the lowest contact of the series being the richest. The ore-bodies were most irregular, varying greatly in size, from a thin seam between schist planes, to very large bodies containing as much as 200,000 cubic metres. The ores are argentiferous galena, accompanied by considerable amounts of blende and pyrites, all oxidized near the surface. The ores worked by the Ancients appear to have been fairly rich in lead, for the discards worked in recent years by the French Company, and the pillars left behind, ran 8% to 10% lead. The ratio of silver was from 40 to 90 ounces per ton of lead. The upper contacts were exposed by erosion and could be entered by tunnels, but the lowest and most prolific contact line was only to be reached by shafts. The shafts were ordinarily from four to six feet square, and were undoubtedly cut by hammer and chisel; they were as much as 380 feet deep. In some cases long inclines for travelling roads join the vertical shafts in depth. The drives, whether tunnels or from shafts, were not level, but followed every caprice of the sinuous contact. They were from two to two and a half feet wide, often driven in parallels with cross-cuts between, in order to exploit every corner of the contact. The stoping of ore-bodies discovered was undertaken quite systematically, the methods depending in the main on the shape of the ore-body. If the body was large, its dimensions were first determined by drives, crosscuts, rises, and [Pg 29]winzes, as the case might require. If the ore was mainly overhead it was overhand-stoped, and the stopes filled as work progressed, inclined winzes being occasionally driven from the stopes to the original entry drives. If the ore was mainly below, it was underhand-stoped, pillars being left if necessary—such pillars in some cases being thirty feet high. They also employed timber and artificial pillars. The mines were practically dry. There is little evidence of breaking by fire. The ore was hand-sorted underground and carried out by the slaves, and in some cases apparently the windlass was used. It was treated by grinding in mills and concentrating upon a sort of buddle. These concentrates—mostly galena—were smelted in low furnaces and the lead was subsequently cupelled. Further details of metallurgical methods will be found in Notes on p. [391] and p. [465], on metallurgical subjects.
The mines were worked by slaves. Even the overseers were at times apparently slaves, for we find (Xenophon, Memorabilia, II., 5) that Nicias paid a whole talent for a good overseer. A talent would be about 837 Troy ounces of silver. As wages of skilled labour were about two and one half pennyweights of silver per diem, and a family income of 100 ounces of silver per annum was affluence, the ratio of purchasing power of Attic coinage to modern would be about 100 to 1. Therefore this mine manager was worth in modern value roughly £8,000. The mines were the property of the State. The areas were defined by vertical boundaries, and were let on lease for definite periods for a fixed annual rent. More ample discussion of the law will be found on p. [83].
[7] Xenophon. (Essay on The Revenues, IV., 30). "I think, however, that I am able to give some advice with regard to this difficulty also (the risk of opening new mines), and to show how new operations may be conducted with the greatest safety. There are ten tribes at Athens, and if to each of these the State should assign an equal number of slaves, and the tribes should all make new cuttings, sharing their fortunes in common, then if but one tribe should make any useful discovery it would point out something profitable to the whole; but if two, three, or four, or half the number should make some discovery, it is plain that the works would be more profitable in proportion, and that they should all fail is contrary to all experience in past times." (Watson's Trans. p. 258).
[8] Agricola here refers to the proposal of Xenophon for the State to collect slaves and hire them to work the mines of Laurion. There is no evidence that this recommendation was ever carried out.
[9] Partes. Agricola, p. [89]-[91], describes in detail the organization and management of these share companies. See [Note 8, p. 90].
[Pg 31][10] This island in the northern Ægean Sea has produced this "earth" from before Theophrastus' time (372-287 B.C.) down to the present day. According to Dana (System of Mineralogy 689), it is cimolite, a hydrous silicate of aluminium. The Ancients distinguished two kinds,—one sort used as a pigment, and the other for medicinal purposes. This latter was dug with great ceremony at a certain time of the year, moulded into cubes, and stamped with a goat,—the symbol of Diana. It thus became known as terra sigillata, and was an article of apothecary commerce down to the last century. It is described by Galen (XII., 12), Dioscorides (V., 63), and Pliny (XXXV., 14), as a remedy for ulcers and snake bites.
[Pg 33][11] Magister Metallorum. See [Note 1, p. 78], for the reasons of the adoption of the term Bergmeister and page [95] for details of his duties.
[12] Ramenta. "Particles." The author uses this term indifferently for fragments, particles of mineral, concentrates, gold dust, black tin, etc., in all cases the result of either natural or artificial concentration. As in technical English we have no general term for both natural and artificial "concentrates," we have rendered it as the context seemed to demand.
[13] A certain amount of bitumen does float ashore in the Dead Sea; the origin of it is, however, uncertain. Strabo (XVI., 2, 42), Pliny (V., 15 and 16), and Josephus (IV., 8), all mention this fact. The lake for this reason is often referred to by the ancient writers by the name Asphaltites.
[Pg 34][14] Excoctor,—literally, "Smelter" or "Metallurgist."
[15] This reference should be to the De Natura Fossilium (p. 230), although there is a short reference to the matter in De Ortu et Causis (p. 59). Agricola maintained that not only were jet and amber varieties of bitumen, but also coal and camphor and obsidian. As jet (gagates) is but a compact variety of coal, the ancient knowledge of this substance has more interest than would otherwise attach to the gem, especially as some materials described in this connection were no doubt coal. The Greeks often refer to a series of substances which burned, contained earth, and which no doubt comprised coal. Such substances are mentioned by Aristotle (De Mirabilibus. 33, 41, 125), Nicander (Theriaca. 37), and others, previous to the 2nd Century B.C., but the most ample description is that of Theophrastus (23-28): "Some of the more brittle stones there also are, which become as it were burning coals when put into a fire, and continue so a long time; of this kind are those about Bena, found in mines and washed down by the torrents, for they will take fire on burning coals being thrown on them, and will continue burning as long as anyone blows them; afterward they will deaden, and may after that be made to burn again. They are therefore of long continuance, but their smell is troublesome and disagreeable. That also which is called the spinus, is found in mines. This stone, cut in pieces and thrown together in a heap, exposed to the sun, burns; and that the more, if it be moistened or sprinkled with water (a pyritiferous shale?). But the Lipara stone empties itself, as it were, in burning, and becomes like the pumice, changing at once both its colour and density; for before burning it is black, smooth, and compact. This stone is found in the Pumices, separately in different places, as it were, in [Pg 35]cells, nowhere continuous to the matter of them. It is said that in Melos the pumice is produced in this manner in some other stone, as this is on the contrary in it; but the stone which the pumice is found in is not at all like the Lipara stone which is found in it. Certain stones there are about Tetras, in Sicily, which is over against Lipara, which empty themselves in the same manner in the fire. And in the promontory called Erineas, there is a great quantity of stone like that found about Bena, which, when burnt, emits a bituminous smell, and leaves a matter resembling calcined earth. Those fossil substances that are called coals, and are broken for use, are earthy; they kindle, however, and burn like wood coals. These are found in Liguria, where there also is amber, and in Elis, on the way to Olympia over the mountains. These are used by smiths." (Based on Hill's Trans.). Dioscorides and Pliny add nothing of value to this description.
Agricola (De Nat. Fos., p. 229-230) not only gives various localities of jet, but also records its relation to coal. As to the latter, he describes several occurrences, and describes the deposits as vena dilatata. Coal had come into considerable use all over Europe, particularly in England, long before Agricola's time; the oft-mentioned charter to mine sea-coal given to the Monks of Newbottle Abbey, near Preston, was dated 1210.
Amber was known to the Greeks by the name electrum, but whether the alloy of the same name took its name from the colour of amber or vice versa is uncertain. The gum is supposed to be referred to by Homer (Od. XV. 460), and Thales of Miletus (640-546 B.C.) is supposed to have first described its power of attraction. It is mentioned by many other Greek authors, Æschylus, Euripides, Aristotle, and others. The latter (De Mirabilibus, 81) records of the amber islands in the Adriatic, that the inhabitants tell the story that on these islands amber falls from poplar trees. "This, they say, resembles gum and hardens like stone, the story of the poets being that after Phaeton was struck by lightning his sisters turned to poplar trees and shed tears of amber." Theophrastus (53) says: "Amber is also a stone; it is dug out of the earth in Liguria and has, like the before-mentioned (lodestone), a power of attraction." Pliny (XXXVII., 11) gives a long account of both the substance, literature, and mythology on the subject. His view of its origin was: "Certainly amber is obtained from the islands of the Northern Ocean, and is called by the Germans glaesum. For this reason the Romans, when Germanicus Cæsar commanded in those parts, called one of them Glaesaria, which was known to the barbarians as Austeravia. Amber originates from gum discharged by a kind of pine tree, like gum from cherry and resin from the ordinary pine. It is liquid at first, and issues abundantly and hardens in time by cold, or by the sea when the rising tides carry off the fragments from the shores of those islands. Certainly it is thrown on the coasts, and is so light that it appears to roll in the water. Our forefathers believed that it was the juice of a tree, for they called it succinum. And that it belongs to a kind of pine tree is proved by the odour of the pine tree which it gives when rubbed, and that it burns when ignited like a pitch pine torch." The term amber is of Arabic origin—from Ambar—and this term was adopted by the Greeks after the Christian era. Agricola uses the Latin term succinum and (De Nat. Fos., p. 231-5) disputes the origin from tree gum, and contends for submarine bitumen springs.
[Pg 36][16] The statement in De Veteribus et Novis Metallis (p. 394) is as follows:—
"It came about by chance and accident that the silver mines were discovered at Freiberg in Meissen. By the river Sala, which is not unknown to Strabo, is Hala, which was once country, but is now a large town; the site, at any rate, even from Roman times was famous and renowned for its salt springs, for the possession of which the Hermunduri fought with the Chatti. When people carried the salt thence in wagons, as they now do straight through Meissen (Saxony) into Bohemia—which is lacking in that seasoning to-day no less than formerly—they saw galena in the wheel tracks, which had been uncovered by the torrents. This lead ore, since it was similar to that of Goslar, they put into their carts and carried to Goslar, for the same carriers were accustomed to carry lead from that city. And since much more silver was smelted from this galena than from that of Goslar, certain miners betook themselves to that part of Meissen in which is now situated Freiberg, a great and wealthy town; and we are told by consistent stories and general report that they grew rich out of the mines." Agricola places the discovery of the mines at Freiberg at about 1170. See [Note 11, p. 5].
[17] Diodorus Siculus (V., 35). "These places being covered with woods, it is said that in ancient times these mountains were set on fire by shepherds, and continued burning for many days, and parched the earth, so that an abundance of silver ore was melted, and the metal flowed in streams of pure silver like a river." Aristotle, nearly three centuries before Diodorus, mentions this same story (De Mirabilibus, 87): "They say that in Ibernia the woods were set on fire by certain shepherds, and the earth thus heated, the country visibly flowed silver; and when some time later there were earthquakes, and the earth burst asunder at different places, a large amount of silver was collected." As the works of Posidonius are lost, it is probable that Agricola was quoting from Strabo (III., 2, 9), who says, in describing Spain: "Posidonius, in praising the amount and excellence of the metals, cannot refrain from his accustomed rhetoric, and becomes quite enthusiastic in exaggeration. He tells us we are not to disbelieve the fable that formerly the forests having been set on fire, the earth, which was loaded with silver and gold, melted and threw up these metals to the surface, for inasmuch as every mountain and wooded hill seemed to be heaped up with money by a lavish fortune." (Hamilton's Trans. I., p. 220). Or he may have been quoting from the Deipnosophistae of Athenaeus (VI.), where Posidonius is quoted: "And the mountains ... when once the woods upon them had caught fire, spontaneously ran with liquid silver."
[Pg 37][18] Lucretius, De Rerum Natura V. 1241.
[19] Agricola's account of this event in De Veteribus et Novis Metallis is as follows (p. 393): "Now veins are not always first disclosed by the hand and labour of man, nor has art always demonstrated them; sometimes they have been disclosed rather by chance or by good fortune. I will explain briefly what has been written upon this matter in history, what miners tell us, and what has occurred in our times. Thus the mines at Goslar are said to have been found in the following way. A certain noble, whose name is not recorded, tied his horse, which was named Ramelus, to the branch of a tree which grew on the mountain. This horse, pawing the earth with its hoofs, which were iron shod, and thus turning it over, uncovered a hidden vein of lead, not unlike the winged Pegasus, who in the legend of the poets opened a spring when he beat the rock with his hoof. So just as that spring is named Hippocrene after that horse, so our ancestors named the mountain Rammelsberg. Whereas the perennial water spring of the poets would long ago have dried up, the vein even to-day exists, and supplies an abundant amount of excellent lead. That a horse can have opened a vein will seem credible to anyone who reflects in how many ways the signs of veins are shown by chance, all of which are explained in my work De Re Metallica. Therefore, here we will believe the story, both because it may happen that a horse may disclose a vein, and because the name of the mountain agrees with the story." Agricola places the discovery of Goslar in the Hartz at prior to 936. See [Note 11, p. 5].
[20] Fragmenta. The glossary gives "Geschube." This term is defined in the Bergwerks' Lexicon (Chemnitz, 1743, p. 250) as the pieces of stone, especially tin-stone, broken from the vein and washed out by the water—the croppings.
[Pg 38][21] So far as we are able to discover, this is the first published description of the divining rod as applied to minerals or water. Like Agricola, many authors have sought to find its origin among the Ancients. The magic rods of Moses and Homer, especially the rod with which the former struck the rock at Horeb, the rod described by Ctesias (died 398 B.C.) which attracted gold and silver, and the virgula divina of the Romans have all been called up for proof. It is true that the Romans are responsible for the name virgula divina, "divining rod," but this rod was used for taking auguries by casting bits of wood (Cicero, De Divinatione). Despite all this, while the ancient naturalists all give detailed directions for finding water, none mention anything akin to the divining rod of the Middle Ages. It is also worth noting that the Monk Theophilus in the 12th Century also gives a detailed description of how to find water, but makes no mention of the rod. There are two authorities sometimes cited as prior to Agricola, the first being Basil Valentine in his "Last Will and Testament" (XXIV-VIII.), and while there may be some reason (see [Appendix]) for accepting the authenticity of the "Triumphal Chariot of Antimony" by this author, as dating about 1500, there can be little doubt that the "Last Will and Testament" was spurious and dated about 50 years after Agricola. Paracelsus (De Natura Rerum IX.), says: "These (divinations) are vain and misleading, and among the first of them are divining rods, which have deceived many miners. If they once point rightly they deceive ten or twenty times." In his De Origine Morborum Invisibilium (Book I.) he adds that the "faith turns the rod." These works were no doubt written prior to De Re Metallica—Paracelsus died in 1541—but they were not published until some time afterward. Those interested in the strange persistence of this superstition down to the present day—and the files of the patent offices of the world are full of it—will find the subject exhaustively discussed in M. E. Chevreul's "De la Baguette Divinatoire," Paris, 1845; L. Figuier, "Histoire du Merveilleux dans les temps moderne II.", Paris, 1860; W. F. Barrett, Proceedings of the Society of Psychical Research, part 32, 1897, and 38, 1900; R. W. Raymond, American Inst. of Mining Engineers, 1883, p. 411. Of the descriptions by those who believed in it there is none better than that of William Pryce (Mineralogia Cornubiensis, London, 1778, pp. 113-123), who devotes much pains to a refutation of Agricola. When we consider that a century later than Agricola such an advanced mind as Robert Boyle (1626-1691), the founder of the Royal Society, was convinced of the genuineness of the divining rod, one is more impressed with the clarity of Agricola's vision. In fact, there were few indeed, down to the 19th Century, who did not believe implicitly in the effectiveness of this instrument, and while science has long since abandoned it, not a year passes but some new manifestation of its hold on the popular mind breaks out.
[Pg 40][22] Exodus VII., 10, 11, 12.
[23] Odyssey XVI., 172, and X., 238.
[Pg 41][24] Odyssey XXIV., 1, etc. The Caduceus of Hermes had also the power of turning things to gold, and it is interesting to note that in its oldest form, as the insignia of heralds and of ambassadors, it had two prongs.
[25] In a general way venae profundae were fissure veins and venae dilatatae were sheeted deposits. For description see [Book III].
[Pg 42][26] These mines are in the Erzgebirge. We have adopted the names given in the German translation.
[27] The quotation from Pliny (XXXIII., 31) as a whole reads as follows:—
"Silver is found in nearly all the provinces, but the finest of all in Spain; where it is found in the barren lands, and in the mountains. Wherever one vein of silver has been found, another is sure to be found not far away. This is the case of nearly all the metals, whence it appears that the Greeks derived metalla. It is wonderful that the shafts begun by Hannibal in Spain still remain, their names being derived from their makers. One of these at the present day called Baebelo, furnished Hannibal with three hundred pounds' weight (of silver) per day. This mountain is excavated for a distance of fifteen hundred paces; and for this distance there are waterbearers lighted by torches standing night and day baling out the water in turns, thus making quite a river." Hannibal dates 247-183 B.C. and was therefore dead 206 years when Pliny was born. According to a footnote in Bostock and Riley's translation of Pliny, these workings were supposed to be in the neighbourhood of Castulo, now Cazlona, near Linares. It was at Castulo that Hannibal married his rich wife Himilce; and in the hills north of Linares there are ancient silver mines still known as Los Pozos de Anibal.
BOOK III.
reviously I have given much information concerning the miners, also I have discussed the choice of localities for mining, for washing sands, and for evaporating waters; further, I described the method of searching for veins. With such matters I was occupied in the second book; now I come to the third book, which is about veins and stringers, and the seams in the rocks[1]. The term "vein" is sometimes used to indicate canales in the earth, but very often elsewhere by this name I have described that which may be put in vessels[2]; I now attach a second significance to these words, for by them I mean to designate any mineral substances which the earth keeps hidden within her own deep receptacles.
The seams in the rocks indicate to us whether a vein runs from the east or from the west. For instance, if the rock seams incline toward the westward as they descend into the earth, the vein is said to run from east to west; if they incline toward the east, the vein is said to run from west to east; in a similar manner, we determine from the rock seams whether the veins run north or south.
When the needle which is governed by the magnet points directly from the north to the south, the number XII at its tail, which is forked, signifies the north, that number XII which is at its point indicates the south. The sign VI superior indicates the east, and VI inferior the west. Further, between each two cardinal points there are always five others which are not so important. The first two of these directions are called the prior directions; the last two are called the posterior, and the fifth direction lies immediately between the former and the latter; it is halved, and one half is attributed to one cardinal point and one half to the other. For example, between the northern number XII and the eastern number VI, are points numbered I, II, III, IV, V, of which I and II are northern directions lying toward the east, IV and V are eastern directions lying toward the north, and III is assigned, half to the north and half to the east.
One who wishes to know the direction of the veins underground, places over the vein the instrument just described; and the needle, as soon as it becomes quiet, will indicate the course of the vein. That is, if the vein proceeds from VI to VI, it either runs from east to west, or from west to east; but whether it be the former or the latter, is clearly shown by the seams in the rocks. If the vein proceeds along the line which is between V and VI toward the opposite direction, it runs from between the fifth and sixth divisions of east to the west, or from between the fifth and sixth divisions of west to the east; and again, whether it is the one or the other is clearly shown by the seams in the rocks. In a similar manner we determine the other directions.
Whether a vein is separating from or uniting with another can be determined only from the seams in the rocks. For example, if a principal vein runs from the east to the west, the rock seams descend in depth likewise from the east toward the west, and the associated vein which joins with the principal vein, whether it runs from the south or the north, has its rock seams extending in the same way as its own, and they do not conform with the seams in the rock of the principal vein—which remain the same after the junction—unless the associated vein proceeds in the same direction as the principal vein. In that case we name the broader vein the principal one, and the narrower the associated vein. But if the principal vein splits, the rock seams which belong respectively to the parts, keep the same course when descending in depth as those of the principal vein.
In truth, as to direction, junctions, and divisions, the stringers are not different from the veins.
But to return to veins. A great number of miners consider[8] that the best veins in depth are those which run from the VI or VII direction of the east to the VI or VII direction of the west, through a mountain slope which inclines to the north; and whose hangingwalls are in the south, and whose footwalls are in the north, and which have their heads rising to the north, as explained before, always like the footwall, and finally, whose rock seams turn their heads to the east. And the veins which are the next best are those which, on the contrary, extend from the VI or VII direction of the west to the VI or VII direction of the east, through the slope of a mountain which similarly inclines to the north, whose hangingwalls are also in the south, whose footwalls are in the north, and whose heads rise toward the north; and lastly, whose rock seams raise their heads toward the west. In the third place, they recommend those veins which extend from XII north to XII south, through the slope of a mountain which faces east; whose hangingwalls are in the west, whose footwalls are in the east; whose heads rise toward the east; and whose rock seams raise their heads toward the north. Therefore they devote all their energies to those veins, and give very little or nothing to those whose heads, or the heads of whose rock seams rise toward the south or west. For although they say these veins sometimes show bright specks of pure metal adhering to the stones, or they come upon lumps of metal, yet these are so few and far between that despite them it is not worth the trouble to excavate such veins; and miners who persevere in digging in the hope of coming upon a quantity of metal, always lose their time and trouble. And they say that from veins of this kind, since the sun's rays draw out the metallic material, very little metal is gained. But in this matter the actual experience of the miners who thus judge of the veins does not always agree with their opinions, nor is their reasoning sound; since indeed the veins which run from east to west through the slope of a mountain which inclines to the south, whose heads rise likewise to the south, are not less charged with metals, than those to which miners are wont to accord the first place in productiveness; as in recent years has been proved by the St. Lorentz vein at Abertham, which our countrymen call Gottsgaab, for they have dug out of it a large quantity of pure silver; and lately a vein in Annaberg, called by the name of Himmelsch hoz[9], has made it plain by the production of much silver that veins which extend from the north to the south, with their heads rising toward the west, are no less rich in metals than those whose heads rise toward the east.
It may be denied that the heat of the sun draws the metallic material out of these veins; for though it draws up vapours from the surface of the ground, the rays of the sun do not penetrate right down to the depths; because the air of a tunnel which is covered and enveloped by solid earth to the depth of only two fathoms is cold in summer, for the intermediate earth holds in check the force of the sun. Having observed this fact, the inhabitants and dwellers of very hot regions lie down by day in caves which protect them from the excessive ardour of the sun. Therefore it is unlikely that the sun draws out from within the earth the metallic bodies. Indeed, it cannot even dry the moisture of many places abounding in veins, because they are protected and shaded by the trees. Furthermore, certain miners, out of all the different kinds of metallic veins, choose those which I have described, and others, on the contrary, reject copper mines which are of this sort, so that there seems to be no reason in this. For what can be the reason if the sun draws no copper from copper veins, that it draws silver from silver veins, and gold from gold veins?
Moreover, some miners, of whose number was Calbus[10], distinguish between the gold-bearing rivers and streams. A river, they say, or a stream, is most productive of fine and coarse grains of gold when it comes from the east and flows to the west, and when it washes against the foot of mountains which are situated in the north, and when it has a level plain toward the south or west. In the second place, they esteem a river or a stream which flows in the opposite course from the west toward the east, and which has the mountains to the north and the level plain to the south. In the third place, they esteem the river or the stream which flows from the north to the south and washes the base of the mountains which are situated in the east. But they say that the river or stream is least productive of gold which flows in a contrary direction from the south to the north, and washes the base of mountains which are situated in the west. Lastly, of the streams or rivers which flow from the rising sun toward the setting sun, or which flow from the northern parts to the southern parts, they favour those which approach the nearest to the lauded ones, and say they are more productive of gold, and the further they depart from them the less productive they are. Such are the opinions held about rivers and streams. Now, since gold is not generated in the rivers and streams, as we have maintained against Albertus[11] in the book entitled "De Subterraneorum Ortu et Causis," Book V, but is torn away from the veins and stringers and settled in the sands of torrents and water-courses, in whatever direction the rivers or streams flow, therefore it is reasonable to expect to find gold therein; which is not opposed by experience. Nevertheless, we do not deny that gold is generated in veins and stringers which lie under the beds of rivers or streams, as in other places.
END OF BOOK III.