A t an early period, while philosophy lay as yet rude and uncultivated in the mists of error and ignorance, few were the virtues and properties of things that were known and clearly perceived: there was a bristling forest of plants and herbs, things metallick were hidden, and the knowledge of stones was unheeded.

Book I chapter 12015-06-05
William GilbertOn the Loadstone, Bk. I. Chap. I. Ancient and Modern Writings on the Loadstone, with certain matters of mention only, various opinions, & vanities. A t an early period, while philosophy lay as yet rude and uncultivated in the mists of error and ignorance, few were the virtues and propert
Book I chapter 22015-06-04
Chap. Ii. Magnet Stone, of what kind it is, and its discovery. L oadstone, the stone which is commonly called the Magnet, derives its name either from the discoverer (though he was not Plinys fabulous herdsman48, quoted from Nicander, the nails of whose shoes and the tip of whose staff stuck fast in
Book I chapter 32015-06-04
Chap. Iii. The Loadstone has parts distinct in their natural power, & poles conspicuous for their property. T he stone itself manifests many qualities which, though known afore this, yet, not having been well investigated, are to be briefly indicated in the first place so that students may understand
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Chap. Iiii. Which pole of the stone is the Boreal: & how it is distinguished from the austral. O ne 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 mot
Book I chapter 52015-06-03
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. F irst of all we must declare, in familiar language, what are the apparent and common virtues of the stone; afterward numerous subtilities, hitherto abstruse and u
Book I chapter 62015-06-02
Chap. vi. Loadstone attracts the ore of iron, as well as iron proper, smelted and wrought. P rincipal 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
Book I chapter 72015-06-02
Chap. vii. What Iron is, and of what substance, and its uses. F or 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 magneti
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Chap. viii. In what countries and districts iron originates. P lenty 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 abou
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Chap. Ix. Iron ore attracts iron ore. F rom 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 veins83, as it were, that they are generated. We have spoken above of the variety of
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Chap. x. Iron ore has poles, and acquires them, and settles itself toward the poles of the universe. D eplorable is mans 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 indu
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Chap. xi. Wrought Iron, not excited by a loadstone, draws iron. F rom 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 a
Book I chapter 122015-05-30
Chap. xii. A long piece of Iron, even though not excited by a loadstone, settles itself toward North and South. E very good and perfect piece of iron, if drawn out in length, points North and South, just as the loadstone or iron rubbed with a magnetical body does; a thing that our famous philosophers
Book I chapter 132015-05-30
Chap. xiii. Wrought iron has in itself certain parts Boreal and Austral: A magnetick vigour, verticity, and determinate vertices, or poles. I ron settles itself toward the North and South; not with one and the same point toward this pole or that: for one end of the piece of ore itself and one extremit
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Chap. xiiii. Concerning other powers of loadstone, and its medicinal properties. D ioscorides prescribes loadstone to be given with sweetened water, three scruples weight, to expel gross humours. Galen writes that a like quantity of bloodstone avails. Others relate that loadstone perturbs the mind an
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Chap. xv. The Medicinal Virtue of Iron. 93N ot foreign to our present purpose will it be to treat briefly also of the medicinal virtue of iron: for it is a prime remedial for some diseases of the human body, and by its virtues, both those that are natural and those acquired by suitable preparation, it
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Chap. xvi. That loadstone & iron ore are the same, but iron an extract from both, as other metals are from their own ores; & that all magnetick virtues, though weaker, exist in the ore itself & in smelted iron. H itherto we have declared the nature & powers of the loadstone, & also the properties & es
Book I chapter 172015-05-28
Chap. xvii. That the globe of the earth is magnetick, & a magnet; & how in our hands the magnet stone has all the primary forces of the earth, while the earth by the same powers remains constant in a fixed direction in the universe. P rior to bringing forward the causes of magnetical motions, & laying
Book II chapter 12015-05-27
Book Second. Chap. I. On Magnetick Motions. D ivers things concerning opinions about the magnet-stone, and its variety, concerning its poles and its known faculties, concerning iron, concerning the properties of iron, concerning a magnetick substance common to both of these and to the earth itself, hav
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Chap. Ii. On the Magnetick Coition, and first on the Attraction of Amber, or more truly, on the Attaching of Bodies to Amber. C elebrated has the fame of the loadstone and of amber ever been in the memoirs of the learned. Loadstone and also amber do some philosophers invoke when in explaining many sec
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Chap. Iii. Opinions of others on Magnetick Coition, which they call Attraction. D iscussion having now been made concerning electricks, the causes of magnetick coition must be set forth. We say coition, not attraction146. The word attraction unfortunately crept into magnetick philosophy from the ignor
Book II Chapter 42015-05-26
Chap. Iiii. On Magnetick Force & Form, what it is; and on the cause of the Coition. R elinquishing the opinions of others on the attraction of loadstone, we shall now show the reason of that coition and the translatory nature of that motion. Since there are really two kinds of bodies, which seem to al
Book II Chapter 52015-05-25
Chap. v. How the Power dwells in the Loadstone. T hat a loadstone attracts loadstone, iron and other magnetical bodies, has been shown above in the previous book, and also with what strength the magnetick coition is ordered; but now we must inquire how that vigour is disposed in a magnetick substance.
Book II Chapter 62015-05-25
How magnetick pieces of Iron and smaller loadstones conform themselves to a terrella & to the earth itself, and by them are disposed. C oition of those bodies which are divided, and do not naturally cohære, if they are free, occurs through another kind of motion. A terrella sends out in an orbe
Book II Chapter 72015-05-24
On the Potency of the Magnetick Virtue, and on its nature capable of spreading out into an orbe. F rom about a magnetical body the virtue magnetical is poured out on every side around in an orbe; around a terrella; in the case of other shapes of stones, more confusedly and unevenly. But yet there exi
Book II Chapter 82015-05-24
On the geography of the Earth, and of the Terrella. D esiring that what follows may be better understood, we must now say something also about magnetick circles and limits. Astronomers, in order to understand and observe methodically the motion of the planets and the revolution of the heavens, and to
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