CHAP. IIII.

Which pole of the stone is the Boreal: & how it is _distinguished from the austral_.

One pole of the earth turns toward the constellation of the Cynosure, and constantly regards a fixed point in the heaven (except so far as it changes by the fixed stars being shifted in longitude, which motion we recognize as existing in the earth, as we shall hereafter prove): While the other pole turns to the opposite face of heaven, unknown to the ancients, now visible on long voyages, and adorned with multitudinous stars: In the same way the loadstone has the property and power of directing itself North and South (the earth herself consenting and contributing force thereto) according to the conformation of nature, which arranges the movements of the stone towards its native situation. Which thing is proved thus: Place a magnetick stone (after finding the poles) in a round wooden vessel, a Bowl or dish, at the same time place it together with the vessel (like a sailor in a skiff) upon water in some large vessel or cistern, so that it may be able to float freely in the middle, nor touch the edge of it, and where the air is not disturbed by winds, which would thwart the natural movement of the stone. Hereupon the stone placed as it were in a ship, in the middle of the surface of the still and unruffled water, will at once put itself in motion along with the vessel that carries it, and revolve circularly, until its austral pole points to the north, and its boreal pole to the south. For it reverts from the contrary position to the poles: and although by the first too-vehement impulse it over-passes the poles; yet after returning again and again, it rests at length at the poles, or at the meridian (unless because of local reasons it is diverted some little from those points, or from the meridional line, by some sort of variation[66], the cause of which we will hereafter state). However often you move it away from its place, so often by virtue of nature's noble dower does it seek again those sure and {15} determined goals; and this is so, not only if the poles have been disposed in the vessel evenly with the plane of the horizon, but also in the case of one pole, whether austral or boreal, being raised in the vessel ten, or twenty, or thirty, or fifty or eighty degrees, above * the plane of the horizon, or lowered beneath it: Still you shall see the boreal part of the stone seek the south, and the austral part seek the north; So much so that if the pole of the stone shall be only one degree distant from the Zenith and highest point of the heaven, in the case of a spherical stone, the whole stone revolves until the pole occupies its own site; though not in the absolutely direct line, it will yet tend toward those parts, and come to rest in the meridian of the directive action. With a like impulse too it is borne if the austral pole have been raised toward the upper quarters, the same as if the Boreal had been exalted above the Horizon. But it is always to be noted that, though there are various kinds of unlikeness in the stones, and one loadstone may far surpass another in virtue and efficiency; yet all hold to the same limits, and are borne toward the same points. Further it is to be remembered * that all who before our time wrote of the poles of the stone, and all the craftsmen and navigators, have been very greatly in error in considering the part of the stone which tended to the north as the north pole of the stone, and that which verged toward the south, the south pole, which we shall hereafter prove to be false. So badly hitherto hath the whole magnetick philosophy been cultivated, even as to its foundation principles.

CHAP. V.

Loadstone seems to attract Loadstone when in natural position: but repels it when in a contrary one, and brings _it back to order_.

First of all we must declare, in familiar language, what are the apparent and common virtues of the stone; afterward numerous subtilities, hitherto abstruse and unknown, hidden in obscurity, are to be laid open, and the causes of all these (by the unlocking of nature's secrets) made evident, in their place, by fitting terms and devices. It is trite and commonplace that loadstone draws iron; in the same way too does loadstone attract loadstone.

Place the stone which you have seen to have poles clearly distinguished, and marked austral and boreal, in its vessel so as to float; and let the poles be rightly arranged with respect to the plane of the horizon, or, at any rate not much raised or awry: hold in your hand another stone the poles of which are also known; in {16} such a way that its austral pole may be toward the boreal pole of the one that is swimming, and near it, sideways: for the floating stone forthwith follows the other stone (provided it be within its force and dominion) and does not leave off nor forsake it until it adhaeres; unless by withdrawing your hand, you cautiously avoid contact.

In like manner if you set the boreal pole of the one you hold in your hand opposite the austral pole of the swimming stone, they rush together and follow each other in turn. For contrary poles allure contrary. If, however, you apply in the same way the northern to the northern, and the austral to the austral pole, the one stone puts the other to flight, and it turns aside as though a pilot were pulling at the helm and it makes sail in the opposite ward as one that ploughs the sea, and neither stands anywhere, nor halts, if the other is in pursuit. For stone disposeth stone; the one turns the other around, reduces it to range, and brings it back to harmony with itself. When, however, they come together and are conjoined according to the order of nature, they cohaere firmly mutually. For instance, if you were to set the boreal pole of that stone which is in your hand before the tropic of Capricorn of a round floating loadstone (for it will be well to mark out on the round stone, that is the terrella, the mathematical circles as we do on a globe itself), or before any point between the aequator and the austral pole; at once the swimming stone revolves, and so arranges itself that its austral pole touches the other's boreal pole, and forms a close union with it. In the same way, again, at the other side of the aequator, with the opposite poles, you may produce similar results; and thus by this art and subtilty we exhibit attraction, repulsion, and circular motion for attaining a position of agreement and for declining hostile encounters. Moreover 'tis in one and the same stone that we are thus able to demonstrate all these things and also how the same part of one stone may on division become either boreal or austral. Let A D be an oblong stone, in which A is the northern, D the southern pole; cut this into two equal parts, then set part A in its vessel on the water[67], so as to float.

[Illustration]

{17} And you will then see[68] that A the northern point will turn to the south, as before; in like manner also the point D will move to the north, in the divided stone, as in the whole one. Whereas, of the parts B and C, which were before continuous, and are now divided, the one is southern B, the other northern C. B draws C, desirous to be united, and to be brought back into its pristine continuity: for these which are now two stones were formed out of one: and for this cause C of the one turning itself to B of the other, they mutually attract each other, and when freed from obstacles and relieved of their own weight, as upon the surface of water, they run together and are conjoined. But if you direct the part or point A to C in the other stone, the one repels or turns away from the other: for so were nature perverted, and the form of the stone perturbed, a form that strictly keeps the laws which it imposed upon bodies: hence, when all is not rightly ordered according to nature, comes the flight of one from the other's perverse position and from the discord, for nature does not allow of an unjust and inequitable peace, or compromise: but wages war and exerts force to make bodies acquiesce well and justly. Rightly arranged, therefore, these mutually attract each other; that is, both stones, the stronger as well as the weaker, run together, and with their whole forces tend to unity, a fact that is evident in all magnets, not in the aethiopian only, as Pliny supposed. The aethiopian magnets if they be powerful, like those brought from China, because all strong ones show the effect more quickly and more plainly, attract more strongly in the parts nearest the pole, and turn about until pole looks directly at pole. The pole of a stone more persistently attracts and more rapidly seizes the corresponding part (which they term the adverse part) of another stone; for instance, North pulls South; just so it also summons iron with more vehemence, and the iron cleaves to it more firmly whether it have been previously excited by the magnet, or is untouched. For thus, not without reason hath it been ordained by nature, that the parts nearer to the pole should more firmly attract: but that at the pole itself should be the seat, the throne, as it were, of a consummate and splendid virtue, to which magnetical bodies on being brought are more vehemently attracted, and from which they are with utmost difficulty dislodged. So the poles are the parts which more particularly spurn and thrust away things strange and alien perversely set beside them.

{18} CHAP. VI.

Loadstone attracts the ore of iron, as well as iron _proper, smelted and wrought_.

Principal and manifest among the virtues of the * magnet, so much and so anciently commended, is the attraction of iron; for Plato states that the magnet, so named by Euripides, allures iron, and that it not only draws iron rings but also indues the rings with power to do the same as the stone; to wit, draw other rings, so that sometimes a long chain of iron objects, nails or rings is formed, some hanging from others. The best iron (like that which is called _acies_ from its use, or _chalybs_ from the country of the Chalybes) is best and strongly drawn by a powerful loadstone; whereas the less good sort, which is impure, rusty, and not thoroughly purged from dross, and not wrought in second furnaces, is more feebly drawn; and yet more weakly when covered and defiled with thick, greasy, and sluggish humours. It also draws ores of iron, those that are rich and of iron colour; the poorer and not so productive ores it does not attract, except they be prepared with some art. A loadstone loses some attractive virtue, and, as it were, pines away with age, if exposed too long to the open air instead of being laid in a case with filings or scales of iron. Whence it should be buried in such materials; for there is nothing that plainly resists this exhaustless virtue which does not destroy the form of the body, or corrode it; not even if a thousand adamants were conjoined. Nor do I consider that there is any such thing as the Theamedes[69], or that it has a power opposite to that of the loadstone.

Although Pliny, that eminent man and prince of compilers (for it is what others had seen and discovered, not always or mainly his own observations, that he has handed down to posterity) has copied from others the fable now made familiar by repetition: That in India there are two mountains near the river Indus; the nature of one being to hold fast all that is iron, for it consists of loadstone; the other's nature being to repel it, for it consists of the Theamedes. Thus if one had iron nails in one's boots, one could not tear away one's foot on the one mountain, nor stand still on the other. Albertus Magnus writes that a loadstone had been found in his day which with one part drew to itself iron, and repelled it with its other end; but Albertus observed the facts badly; for every loadstone attracts with one end iron that has been touched with a loadstone, and drives it away with the other; and draws iron that been touched with a loadstone more powerfully than iron that has not been so touched.

{19} CHAP. VII.

What Iron is, and of what substance, _and its uses._

For that now we have declared the origin and nature of the loadstone, we think it necessary first to add a history of iron and to indicate the hitherto unknown forces of iron, before this our discourse goes on to the explanation of magnetick difficulties and demonstrations, and to deal with the coitions and harmonies of loadstone with iron. Iron is by all reckoned in the class of metals, and is a metal livid in colour, very hard, glows red-hot before it melts, being most difficult of fusion, is beaten out under the hammer, and is very resonant. Chemists say that if a bed of fixed earthy sulphur be combined with fixed earthy quicksilver, and the two together are neither pure white but of a livid whiteness, if the sulphur prevail, iron is formed. For these stern masters of metals who by many inventions twisting them about, pound, calcine, dissolve, sublime, and precipitate, decide that this metal, both on account of the earthy sulphur and of the earthy mercury, is more truly a son of the earth than any other; they do not even think gold or silver, lead, tin, or copper itself so earthy; for that reason it is not smelted except in the hottest furnaces, with bellows; and when thus fused, on having again grown hard it is not melted again without heavy labour; but its slag with the utmost difficulty.

It is the hardest of metals, subduing and breaking all things, by reason of the strong concretion of the more earthy matter. Wherefore we shall better understand what iron is, when we shall declare what are the causes and substance of metals, in a different way from those who before our time have considered them. Aristotle takes the material of the metals to be vapour.

The chemists in chorus pronounce their actual elements to be sulphur and quicksilver. Gilgil Mauritanus gives it as ashes moistened with water.

Georgius Agricola makes it out to be water and earth mixed; nor, to be sure, is there any difference between his opinion and the position taken by Mauritanus. But ours is that metals arise and effloresce at the summits of the earth's globe, being distinguished each by its own form, like some of the other substances dug out of it, and all bodies around us. The earth's globe does not consist of ashes or inert dust. Nor is fresh water an element, but a more simple consistency of evaporated fluids of the earth.

Unctuous bodies, fresh water devoid of properties, quicksilver and sulphur, none of these are principia of metals: these latter, {20} things are the results of a different nature, they are neither constant nor antecedent in the course of the generation of metals. The earth emits various humours, not begotten of water nor of dry earth, nor from mixtures of these, but from the substance of the earth itself: these humours are not distinguished by contrary qualities or substance, nor is the earth a simple substance, as the Peripateticks dream. The humours proceed from vapours sublimated from great depths; all waters are extracts and, as it were, exudations from the earth. Rightly then in some measure does Aristotle make out the matter of metals to be that exhalation which in continuance thickens in the lodes of certain soils: for the vapours are condensed in places which are less hot than the spot whence they issued, and by help of the nature of the soils and mountains, as in a womb, they are at fitting seasons congealed and changed into metals: but it is not they alone which form ores, but they flow into and enter a more solid material, and so form metals. So when this concreted matter has settled down in more temperate beds, it begins to take shape in those tepid places, just as seed in the warm womb, or as the embryo acquires growth: sometimes the vapour conjoins with suitable matter alone: hence some metals are occasionally though rarely dug up native, and come into existence perfect without smelting: but other vapours which are mixed with alien soils require smelting in the way that the ores of all metals are treated, which are rid of all their dross by the force of fires, and being fused flow out metallick, and are separated from earthy impurities but not from the true substance of the earth. But in so far as that it becomes gold, or silver, or copper, or any other of the existing metals, this does not happen from the quantity or proportion of material, nor from any forces of matter, as the Chemists fondly imagine; but when the beds and region concur fitly with the material, the metals assume forms from the universal nature by which they are perfected; in the same manner as all the other minerals, plants, and animals whatever: otherwise the species of metals would be vague and undefined, which are even now turned up in such scanty numbers that scarce ten kinds are known. Why, however, nature has been so stingy as regards the number of metals, or why there should be as many as are known to man, it is not easy to explain; though the simple-minded and raving Astrologers refer the metals each to its own planet. But there is no agreement of the metals with the planets, nor of the planets with the metals, either in numbers or in properties. For what connexion is there of iron with Mars? unless it be that from the former numerous instruments, particularly swords and engines of war, are fashioned. What has copper to do with Venus? or how does tin, or how does spelter correspond with Jupiter? They should rather be dedicated to Venus.

But this is old wives' talk. Vapour is then a remote cause in the generation of the metals; the fluid condensed from {21} vapours is a more proximate one, like the blood and semen in the generation of animals. But those vapours and juices from vapours pass for the most part into bodies and change them into marcasites and are carried into lodes (for we have numerous cases of wood so transmuted), the fitting matrices of bodies, where they are formed as metals. They enter most often into the truer and more homogeneal substance of the globe, and in the process of time a vein of iron results; loadstone is also produced, which is nought else than a noble kind of iron ore: and for this reason, and on account of its substance being singular, alien from all other metals, nature very rarely, if ever, mixes with iron any other metal, while the other metals are very often minutely mixed, and are produced together. Now when that vapour or those juices happen to meet, in fitting matrices, with efflorescences deformed from the earth's homogenic substance, and with divers precipitates (the forms working thereto), the remainder of the metals are generated (a specifick nature affecting the properties in that place). For the hidden primordial elements of metals and stones lie concealed in the earth, as those of herbs and plants do in its outer crust. For the soil dug out of a deep well, where would seem to be no suspicion of a conception of seed, when placed on a very high tower, produces, by the incubation of sun and sky, green herbage and unbidden weeds; and those of the kind which grow spontaneously in that region, for each region produces its own herbs and plants, also its own metals.

_[70]Here corn exults, and there the grape is glad,_ _Here trees and grass unbidden verdure add._ _So mark how Tmolus yields his saffrone store,_ _But ivory is the gift of Indian shore;_ _With incense soft the softer Shebans deal;_ _The stark Chalybeans' element is steel:_ _With acrid castor reek the Pontic wares,_ _Epirus wins the palm of Elian mares._

But what the Chemists (as Geber, and others) call fixed earthy sulphur in iron is nothing else than the homogenic earth-substance concreted by its own humour, amalgamated with a double fluid: a metallick humour is inserted along with a small quantity of the substance of the earth not devoid of humour. Wherefore the common saying that in gold there is pure earth, but in iron mostly impure, is wrong; as though there were indeed such a thing as natural earth, and that the globe itself were (by some unknown process of refining) depurate. In iron, especially in the best iron, there is earth in its own nature true and genuine; in the other metals there is not so much earth as that in place of earth and precipitates there are consolidated and (so to speak) fixed salts, which are efflorescences of the globe, and which differ also greatly {22} in firmness and consistency: In the mines their force rises up along with a twofold humour from the exhalations, they solidify in the underground spaces into metallic veins: so too they are also connate by virtue of their place and of the surrounding bodies, in natural matrices, and take on their specific forms.

Of the various constitutions of loadstones and their diverse substances, colours, and virtues, mention has been made before: but, now having stated the cause and origin of metals, we have to examine ferruginous matter not as it is in the smelted metal, but as that from which the metal is refined.

Quasi-pure iron is found of its proper colour and in its own lodes; still, not as it will presently be, nor as adapted for its various uses. It is sometimes dug up covered with white silex or with other stones. It is often the same in river sand, as in Noricum. A nearly pure ore of iron is now often dug up in Ireland, which the smiths, without the labours of furnaces, hammer out in the smithy into iron implements. In France iron is very commonly smelted out of a liver-coloured stone, in which are glittering scales; the same kind[71] without the scales is found in England, which also they use for craftsmen's ruddle[72]. In Sussex in England[73] is a rich dusky ore and also one of a pale ashen hue, both of which on being dried for a time, or kept in moderate fires, presently acquire a liver-colour; here also is found a dusky ore square-shaped with a black rind of greater hardness. An ore having the appearance of liver is often variously intermingled with other stones: as also with the perfect loadstone which yields the best of iron. There is also a rusty ore of iron, one of a leaden hue tending to black, one quite black, or black mixed with true cobalt: there is another sort mixed either with pyrites, or with sterile plumbago. One kind is also like jet, another like bloodstone. The emery used by armourers, and by glaziers for glass-cutting, called amongst the English Emerelstone, by the Germans Smeargel, is ferruginous; albeit iron is extracted from it with difficulty, yet it attracts the versorium.

It is now and then found in deep iron and silver diggings. Thomas Erastus says he had heard from a certain learned man of iron ores, of the colour of iron, but quite soft and fatty, which can be smoothed with the fingers like butter, out of which excellent iron can be smelted: somewhat the same we have seen found in England, having the aspect of Spanish soap. Besides the numberless kinds of stony ores, iron is extracted from clay, from clayey earth, from ochre, from a rusty matter deposited from chalybeate waters; In England iron is copiously extracted in furnaces often from sandy and clayey stones which appear to contain iron not more than sand, marl, or any other clay soils contain it. Thus in Aristotle's book _De Mirabilibus Auscultationibus_[74], "There is said" (he states) "to be a peculiar formation of Chalybean and Misenian iron, for instance the sort collected from river gravel; some say {23} that after being simply washed it is smelted in the furnace; others declare that it and the sediment which subsides after several washings are cast in and purified together by the fire; with the addition of the stone pyrimachus which is found there in abundance." Thus do numerous sorts of things contain in their various substances notably and abundantly this element of iron and earth. However, there are many stones, and very common ones, found in every soil, also earths, and various and mixed materials, which do not hold rich substances, but yet have their own iron elements, and yield them to skilfully-made fires, yet which are left aside by metallick men because they are less profitable; while other soils give some show of a ferruginous nature, yet (being very barren) are hardly ever smelted down into iron; and being neglected are not generally known. Manufactured irons differ very greatly amongst themselves. For one kind is tenacious in its nature, and this is the best; one is of medium quality: another is brittle, and this is the worst. Sometimes the iron, by reason of the excellency of the ore, is wrought into steel, as to-day in Noricum. From the finest iron, too, well wrought and purged from all dross, or by being plunged in water after heating, there issues what the Greeks call [Greek: stomoma]; the Latins _acies;_ others _aciarium,_ such as was at times called Syrian, Parthian, Noric, Comese, Spanish; elsewhere it is named from the water in which it is so often plunged, as at Como in Italy[75], Bambola and Tarazona in Spain.

_Acies_ fetches a much larger price than mere iron. And owing to its superiority it better accords with the loadstone, from which more powerful quality it is often smelted, and it acquires the virtues from it more quickly, retains them longer at their full, and in the best condition for magnetical experiments. After iron has been smelted in the first furnaces, it is afterward wrought by various arts in large worksteads or mills, the metal acquiring consistency when hammered with ponderous blows, and throwing off the dross. After the first smelting it is rather brittle and by no means perfect. Wherefore with us (English) when the larger military guns are cast, they purify the metal from dross more fully, so that they may be stronger to withstand the force of the firing; and they do this by making it pass again (in a fluid state) through a chink, by which process it sheds its recremental matter. Smiths render iron sheets tougher with certain liquids, and by blows of the hammer, and from them make shields and breastplates that defy the blows of battle-axes. Iron becomes harder through skill and proper tempering, but also by skill turns out in a softer condition and as pliable as lead. It is made hard by the action of certain waters into which while glowing it is plunged, as at Bambola and Tarazona in Spain: It grows soft again, either by the effect of fire alone, when without hammering and without water, it is left to cool by itself; or by that of grease into which it is plunged; or {24} (that it may the better serve for various trades) it is tempered variously by being skilfully besmeared. Baptista Porta expounds this art in book 13 of his _Magia Naturalis_. Thus this ferric and telluric nature is included and taken up in various bodies of stones, ores, and earths; so too it differs in aspect, in form, and in efficiency. Art smelts it by various processes, improves it, and turns it, above all material substances, to the service of man in trades and appliances without end. One kind of iron is adapted for breastplates, another serves as a defence against shot, another protects against swords and curved blades (commonly called scimitars), another is used for making swords, another for horseshoes. From iron are made nails, hinges, bolts, saws, keys, grids, doors, folding-doors, spades, rods, pitchforks, hooks, barbs, tridents, pots, tripods, anvils, hammers, wedges, chains, hand-cuffs, fetters, hoes, mattocks, sickles, baskets, shovels, harrows, planes, rakes, ploughshares, forks, pans, dishes, ladles, spoons, spits, knives, daggers, swords, axes, darts, javelins, lances, spears, anchors, and much ship's gear. Besides these, balls, darts, pikes, breastplates, helmets, cuirasses, horseshoes, greaves, wire, strings of musical instruments, chairs, portcullises, bows, catapults, and (pests of human kind) cannon, muskets, and cannon-balls, with endless instruments unknown to the Latins: which things I have rehearsed in order that it may be understood how great is the use of iron, which surpasses a hundred times that of all the other metals; and is day by day being wrought by metal-workers whose stithies are found in almost every village. For this is the foremost of metals, subserving many and the greatest needs of man, and abounds in the earth above all other metals, and is predominant. Wherefore those Chemists are fools[76] who think that nature's will is to perfect all metals into gold; she might as well be making ready to change all stones to diamonds, since diamond surpasses all in splendour and hardness, because gold excels in splendour, gravity, and density, being invincible against all deterioration. Iron as dug up is therefore, like iron that has been smelted, a metal, differing a little indeed from the primary homogenic terrestrial body, owing to the metallick humour it has imbibed; yet not so alien as that it will not, after the manner of refined matter, admit largely of the magnetick forces, and may be associated with that prepotent form belonging to the earth, and yield to it a due submission.

* * * * * {25}

CHAP. VIII.

In what countries and districts iron _originates._

Plenty of iron mines exist everywhere, both those of old time recorded in early ages by the most ancient writers, and the new and modern ones. The earliest and most important seem to me to be those of Asia. For in those countries which abound naturally in iron, governments and the arts flourished exceedingly, and things needful for the use of man were discovered and sought after. It is recorded to have been found about Andria, in the region of the Chalybes near the river Thermodon in Pontus; in the mountains of Palestine which face Arabia; in Carmania: in Africa there was a mine of iron in the Isle of Meroe; in Europe in the hills of Britain, as Strabo writes; in Hither Spain, in Cantabria. Among the Petrocorii and Cubi Biturges[77] (peoples of Gaul), there were worksteads in which iron used to be wrought. In greater Germany near Luna, as recorded by Ptolemy; Gothinian iron is mentioned by Cornelius Tacitus; Noric iron is celebrated in the verses of poets; and Cretan, and that of Euboea; many other iron mines were passed over by these writers or unknown to them; and yet they were neither poor nor scanty, but most extensive. Pliny[78] says that Hither Spain and all the district from the Pyrenees is ferruginous, and on the part of maritime Cantabria washed by the Ocean (says the same writer) there is (incredible to relate) a precipitously high mountain wholly composed of this material. The most ancient mines were of iron rather than of gold, silver, copper or lead; since mainly this was sought because of the demand; and also because in every district and soil they were easy to find, not so deep-lying, and less beset by difficulties. If, however, I were to enumerate modern iron workings, and those of this age and over Europe only, I should have to write a large and bulky volume, and sheets of paper would run short quicker than the iron, and yet for one sheet they could furnish a thousand worksteads. For amongst minerals, no material is so ample; all metals, and all stones distinct from iron, are outdone by ferric and ferruginous matter. For you will not readily find any region, and scarcely any country district over the whole of Europe (if you search at all deeply), that does not either produce a rich and abundant vein of iron or some soil containing or slightly charged with ferruginous stuff; and that this is {26} true any expert in the arts of metals and chemistry will easily find. Beside that which has ferruginous nature, and the metallick lode, there is another ferric substance which does not yield the metal in this way because its thin humour is burnt out by fierce fires, and it is changed into an iron slag like that which is separated from the metal in the first furnaces. And of this kind is all clay and argillaceous earth, such as that which apparently forms a large part of the whole of our island of Britain: all of which, if subjected very vehemently to intense heat, exhibits a ferric and metallick body, or passes into ferric vitreous matter, as can be easily seen in buildings in bricks baked from clay, which, when placed next the fires in the open kilns (which our folk call _clamps_)[79] and burned, present an iron vitrification, black at the other end. Moreover all those earths as prepared are drawn by the magnet, and like iron are attracted by it. So perpetual and ample is the iron offspring of the terrestrial globe. Georgius Agricola says that almost all mountainous regions are full of its ores, while as we know a rich iron lode is frequently dug in the open country and plains over nearly the whole of England and Ireland; in no other wise than as, says he, iron is dug out of the meadows at the town of Saga in pits driven to a two-foot depth. Nor are the West Indies without their iron lodes, as writers tell us; but the Spaniards, intent upon gold, neglect the toilsome work of iron-founding, and do not search for lodes and mines abounding in iron. It is probable that nature and the globe of the earth are not able to hide, and are evermore bringing to the light of day, a great mass of inborn matter, and are not invariably obstructed by the settling of mixtures and efflorescences at the earth's surface. It is not only in the common mother (the terrestrial globe) that iron is produced, but sometimes also in the air from the earth's exhalations, in the highest clouds. It rained iron in Lucania, the year in which M. Crassus was slain. The tale is told, too, that a mass of iron, like slag, fell from the air in the Nethorian forest, near Grina, and they narrate that the mass was many pounds in weight; so that it could neither be conveyed to that place, on account of its weight, nor be brought away by cart, the place being without roads. This happened before the civil war waged between the rival dukes in Saxony. A similar story, too, comes to us from Avicenna. It once rained iron in the Torinese[80], in various places (Julius Scaliger telling us that he had a piece of it in his house), about three years before that province was taken over by the king. In the year 1510 in the country bordering on the river Abdua (as Cardan writes[81] in his book _De Rerum Varietate_) there fell from the sky 1200 stones, one weighing 120 pounds, another 30 or 40 pounds, of a rusty iron colour and remarkably hard. These occurrences being rare are regarded as portents, like the showers of earth and stones mentioned in Roman history. But that it ever rained other metals is not {27} recorded; for it has never been known to rain from the sky gold, silver, lead, tin, or spelter[82]. Copper, however, has been at some time noticed to fall from the sky, and this is not very unlike iron; and in fact cloud-born iron of this sort, or copper, are seen to be imperfectly metallick, incapable of being cast in any way, or wrought with facility. For the earth hath of her store plenty of iron in her highlands, and the globe contains the ferric and magnetick element in rich abundance. The exhalations forcibly derived from such material may well become concreted in the upper air by the help of more powerful causes, and hence some monstrous progeny of iron be begotten.

CHAP. IX.

Iron ore attracts iron ore.

From various substances iron (like all the rest of the * metals) is extracted: such substances being stones, earth, and similar concretions which miners call veins because it is in veins[83], as it were, that they are generated. We have spoken above of the variety of these veins. If a properly coloured ore of iron and a rich one (as miners call it) is placed, as soon as mined, upon water in a bowl or any small vessel (as we have shown before in the case of a loadstone), it is attracted by a similar piece of ore brought near by hand, yet not so powerfully and quickly as one loadstone is drawn by another loadstone, but slowly and feebly. Ores of iron that are stony, cindery, dusky, red, and several more of other colours, do not attract one another mutually, nor are they attracted by the loadstone itself, even by a strong one, no more than wood, or lead, silver, or gold. Take those ores and burn, or rather roast them, in a moderate fire, so that they are not suddenly split up, or fly asunder, keeping up the fire ten or twelve hours, and gently increasing it, then let them grow cold, skill being shown in the direction in which they are placed: These ores thus prepared a loadstone will now draw, and they now show a mutual sympathy, and when skilfully arranged run together by their own forces.

{28}

CHAP. X.

Iron ore has poles, and acquires them, and settles _itself toward the poles of the universe_.

Deplorable is man's ignorance in natural science, and modern philosophers, like those who dream in darkness, need to be aroused, and taught the uses of things and how to deal with them, and to be induced to leave the learning sought at leisure from books alone, and that is supported only by unrealities of arguments and by conjectures. For the knowledge of iron (than which nothing is in more common use), and that of many more substances around us, remains unlearned; iron, a rich ore of which, placed in a vessel upon water, by an innate property of its own directs itself, just like the loadstone, North and South, at which points it rests, and to which, if it be turned aside, it reverts by its own inherent vigour. But many ores, less perfect in their nature, which yet contain amid stone or earthy substances plenty of iron, have no such motion; but when prepared by skilful treatment in the fires, as shown in the foregoing chapter, they acquire a polar vigour (which we call verticity[84]); and not only the iron ores in request by miners, but even earth merely charged with ferruginous matter, and many rocks, do in like manner tend and lean toward those portions of the heavens, or more truly of the earth, if they be skilfully placed, until they reach the desired location, in which they eagerly repose.

{29} CHAP. XI.

Wrought Iron, not excited by a loadstone, _draws iron_.

From the ore, which is converted, or separated, partly into metal, partly into slag, by the intense heat of fires, iron is smelted in the first furnaces in a space of eight, ten, or twelve hours, and the metal flows away from the dross and useless matter, forming a large and long mass, which being subjected to a sharp hammering is cut into parts, out of which when reheated in the second hearth of the forge, and again placed on the anvil, the smiths fashion quadrangular lumps, or more specially bars which are bought by merchants and blacksmiths, from which in smithies usually it is the custom to fashion the various implements. This iron we term _wrought_, and its attraction by the loadstone is manifest to all. But we, by more carefully trying everything[85], have found out that iron merely, by itself alone, not excited by any loadstone, not charged by any alien forces, attracts other iron; though it does not so eagerly snatch and suddenly pluck at it as would a fairly strong loadstone; this you may know thus: A small piece of cork, the size of a hazel-nut, rounded, is traversed by an iron wire up to the middle of the wire: when set swimming on still water apply to one end of it, close (yet so as not to touch), the end of another iron wire; and wire draws wire, and one follows the other when slowly drawn back, and this goes on up to the proper boundaries. Let A be the cork with the iron wire, B one end of it raised a little above the surface of the water, C the end of the second wire, showing the way in which B is drawn by C. You may prove it in another way in a larger body.

Let a long bright iron rod (such as is made for hangings and window curtains) be hung in balance by a slender silken cord: to one end of this as it rests in the air bring a small oblong mass of polished iron, with its proper {30} end at the distance of half a digit. The balanced iron turns itself to the mass; do you with the same quickness draw back the mass in your hand in a circular path about the point of equilibrium of the suspension; the end of the balanced iron follows after it, and turns in an orbit.