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54-639: De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure ( On the Magnet and Magnetic Bodies, and on That Great Magnet the Earth ) is a scientific work published in 1600 by the English physician and scientist William Gilbert . A highly influential and successful book, it exerted an immediate influence on many contemporary writers, including Francis Godwin and Mark Ridley . In De Magnete , Gilbert described many of his experiments with his model Earth called

108-566: A crusader ; and the attack on Lucera of 1269 had been sanctioned as a crusade by the Pope . So Petrus Peregrinus may have served in that army. "You must realize, dearest friend," Peregrinus writes, "that while the investigator in this subject must understand nature and not be ignorant of the celestial motions, he must also be very diligent in the use of his own hands, so that through the operation of this stone he may show wonderful effects." In his letter of 1269, Peregrinus explains how to identify

162-471: A dip instrument . At the equator it is level and increases towards the poles as he has shown earlier with his terrella. Terrestrial rotation . Heraclides and others held that the Earth rotates from west to east and this is supported by Copernicus (the "restorer of astronomy"), but Aristotle said otherwise. "If the rotations of the earth seems headlong and not to be permitted by nature because of its rapidity, then worse than insane, both as regards itself and

216-402: A marginal gloss to Bacon's Opus tertium and only in one of the five manuscripts used in the critical edition, which leads us to conclude that it was a later comment added by someone else. That Bacon's praise was for Peregrinus is open to serious debate. The influence of Peregrinus's astrolabe was virtually nil. His reputation derives mainly from his work on magnetism. The De magnete became

270-417: A "dry" pivoted compass in some detail. He also attempts to prove that with the help of magnets it is possible to realize perpetual motion (see History of perpetual motion machines ). His device is a toothed wheel which passes near a lodestone so that the teeth are alternately attracted by one pole and repelled by the other. The Nova Compositio Astrolabii Particularis (found in only 4 manuscripts) describes

324-426: A more distinct statement of the attraction of one body by another. "The force which emanates from the moon reaches to the earth, and, in like manner, the magnetic virtue of the earth pervades the region of the moon: both correspond and conspire by the joint action of both, according to a proportion and conformity of motions, but the earth has more effect in consequence of its superior mass; the earth attracts and repels,

378-503: A new magnet with north and south poles. In Book 6, Chapter 3 , he argues in support of diurnal rotation though he does not talk about heliocentrism, stating that it is an absurdity to think that the immense celestial spheres (doubting even that they exist) rotate daily, as opposed to the diurnal rotation of the much-smaller Earth. He also posits that the "fixed" stars are at remote variable distances rather than fixed to an imaginary sphere. He states that, situated "in thinnest aether, or in

432-666: A new system of natural philosophy upon the ruins of the Aristotelian doctrine. William Whewell says in his History of the Inductive Sciences (1859): Gilbert, in his work, De Magnete printed in 1600 has only some vague notions that the magnetic virtue of the earth in some way determines the direction of the earth's axis, the rate of its diurnal rotation, and that of the revolution of the moon about it. Gilbert died in 1603, and in his posthumous work ( De Mundo nostro Sublunari Philosophia nova , 1631) we have already

486-518: A philosophy out of observations of the lodestone. [Gilbert] has himself become a magnet; that is, he has ascribed too many things to that force and built a ship out of a shell. Thomas Thomson writes in his History of the Royal Society (1812): The magnetic laws were first generalized and explained by Dr. Gilbert, whose book on magnetism published in 1600, is one of the finest examples of inductive philosophy that has ever been presented to

540-412: A physician, in his Latin treatise on the magnet, not only collected all the knowledge which others had possessed on that subject, but became at once the father of experimental philosophy in this island, and by a singular felicity and acuteness of genius, the founder of theories which have been revived after the lapse of ages, and are almost universally received into the creed of the science. The magnetism of

594-400: A quarto volume of 316 pages entitled De Mundo Nostro Sublunari Philosophia Nova (New Philosophy about our Sublunary World), edited – some say by his brother William Gilbert Junior, and others say, by the eminent English scholar and critic John Gruter – from two manuscripts found in the library of Sir William Boswell . According to John Davy , "this work of Gilbert's, which is so little known,

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648-464: A very popular work from the Middle Ages onwards, as witnessed by the large number of manuscript copies. The first printed edition of it was issued at Augsburg , in 1558, by Achilles Gasser . In 1562, Jean Taisner published from the press of Johann Birkmann of Cologne a work entitled Opusculum perpetua memoria dignissimum, de natura magnetis et ejus effectibus, Item de motu continuo . This

702-459: Is a very remarkable one both in style and matter; and there is a vigor and energy of expression belonging to it very suitable to its originality. Possessed of a more minute and practical knowledge of natural philosophy than Bacon , his opposition to the philosophy of the schools was more searching and particular, and at the same time probably little less efficient." In the opinion of Prof. John Robison , De Mundo consists of an attempt to establish

756-437: Is considerable variation. Using the terrella he shows that variations in the height of the surface can lead to differences but insists that variation is a global issue. In the midst of the ocean or continent there is no variation. He shows how to measure variation and the sources of common errors. Magnetic dip . The angle of inclination (dip) of a compass to the horizon differs according to latitude . He shows how to construct

810-623: Is considered a piece of plagiarism , as Taisnier presents, as though his own, the Epistola de magnete of Peregrinus and a treatise on the fall of bodies by Gianbattista Benedetti . William Gilbert acknowledged his debt to Peregrinus and incorporated this thirteenth-century scientist's experiments on magnetism into his own treatise, called De magnete . The Epistola de magnete was later issued by Guillaume Libri ( Histoire des sciences mathématiques en Italie , vol 2 [Paris, 1838], pp. 487–505), but, based on only one manuscript, this edition

864-403: Is divided into two parts. Part One (10 chapters): This is a section that serves as a model of inductive reasoning based on definite experiences, and setting forth the fundamental laws of magnetism. He did not discover these laws, but presented them in logical order. Part One discusses the physical (but not the occult) properties of the lodestone and provides the first extant written account of

918-490: Is thought to have been the bubonic plague . Gilbert was buried in his home town, in Holy Trinity Church, Colchester. His marble wall monument can still be seen in this Saxon church, now deconsecrated and used as a café and market. Francis Bacon never accepted Copernican heliocentrism , and was critical of Gilbert's philosophical work in support of the diurnal motion of Earth. Bacon's criticism includes

972-437: Is very complicated, and since it is probable that most sophisticated users were not frequent travelers, they were more likely happier with the traditional (and simpler) stereographic planispheric astrolabe. The literature often mentions that Peregrinus was praised by Roger Bacon , who called him a "perfect mathematician" and one who valued experience over argument. But the association of the praise with Peregrinus appears only in

1026-672: The terrella . Gilbert made the claim that gravity was due to the same force and he believed that this held the Moon in orbit around the Earth. The work then considered static electricity produced by amber . Amber is called elektron in Greek, and electrum in Latin, so Gilbert decided to refer to the phenomenon by the adjective electricus . De Magnete consists of six books. Historical survey of magnetism and theory of Earth's magnetism . The lodestone in antiquity from Plato onwards and

1080-401: The polarity of magnets. He was thus the first to use the word " pole " in this context. He provides methods for determining the north and south poles of a magnet, and he describes the effects magnets have upon one another, showing that like poles repel each other and unlike poles attract each other. He also treats the attraction of iron by lodestones, the magnetization of iron by lodestones, and

1134-463: The terrella . From these experiments, he concluded that Earth was itself magnetic , and that this was the reason why compasses point north (previously, some people believed that it was the pole-star Polaris , or a large magnetic island on the north pole that attracted the compass). He was the first person to argue that the center of Earth was iron, and he considered an important and related property of magnets, being that they can be cut, each forming

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1188-473: The Earth's pole to the ecliptic produces the seasons. He explains the precession of the equinoxes as the movement of the Earth's axis. In Chapter III, Gilbert argues in favor of the Copernican System . He posits that due to the inordinate distance of the celestial spheres, if in fact the spheres exist at all, it is an absurd idea that they would rotate every 24 hours, as opposed to the rotation of

1242-550: The Magnet"). The letter is addressed to an otherwise unknown Picard countryman named Sygerus (Sigerus, Ysaerus) of Foucaucourt , possibly a friend and neighbor of the author; Foucaucourt borders on the home area of Peregrinus around Maricourt, in the present-day department of the Somme , near Péronne . In only one of the 39 surviving manuscript copies the letter also bears the closing legend Actum in castris in obsidione Luceriæ anno domini 1269º 8º die augusti ("Done in camp during

1296-610: The Magnet", [London: Chiswick Press, 1902]); by Brother Arnold [=Joseph Charles Mertens] ("The Letter of Petrus Peregrinus on the Magnet, A.D. 1269", with introductory note by Brother Potamian [= M. F. O'Reilly], [New York, 1904]); and H. D. Harradon, ("Some Early Contributions to the History of Geomagnetism - I," in Terrestrial Magnetism and Atmospheric Electricity [now Journal of Geophysical Research ] 48 [1943], 3–17 [text pp. 6–17]). The modern critical edition of

1350-417: The ability to reverse the polarity in such an induced magnet. Peregrinus attributed the Earth's magnetism to the action of celestial poles, rather than to the terrestrial poles of the planet itself. Part Two (three chapters): This section describes three devices that utilize the properties of magnets. He treats the practical applications of magnets, describing the "wet" floating compass as an instrument, and

1404-497: The angle of the ecliptic and precession of the equinoxes are caused by magnetism. A lodestone cut out of rock and floated in water returns to the same direction. Iron heated to white heat and cooled lying along a meridian also acquires magnetism. But stroking with other materials fails—he proved this with an experiment with 75 diamonds in front of witnesses. The best way to magnetize a compass (magnetized versorium). Declination . The compass does not always point to true north. There

1458-690: The astrolabe text was prepared by Ron B. Thomson and appears in Petrus Peregrinus de Maricourt, Opera (Pisa, 1995), pp. 119–196. The philosopher and scientist Charles S. Peirce made a thorough study the Epistle of Petrus Peregrinus on the lodestone (MS. No. 7378; See Eisele, C. (1957) The Charles S. Peirce-Simon Newcomb Correspondence. Proceedings of the American Philosophical Society, Vol. 101, No. 5. p. 411). The European Geosciences Union (EGU) established

1512-409: The body emitting the effluvium. In his book, he also studied static electricity using amber ; amber is called elektron in Greek, so Gilbert decided to call its effect the electric force . He invented the first electrical measuring instrument , the electroscope , in the form of a pivoted needle he called the versorium . Like other people of his day, he believed that crystal (clear quartz )

1566-498: The construction and use of a universal astrolabe which could be used at a variety of latitudes without changing the plates. Unlike al-Zarqālī 's more famous universal astrolabe in which vertical halves the heavens were projected onto a plane through the poles, this one had both the northern and southern hemispheres projected onto a plane through the equator (which was also the limit of projection). There are no known surviving astrolabes based on this treatise. The use of such an astrolabe

1620-437: The earth itself, his own original hypothesis, nova illa nostra et inaudita de tellure sententia [our new and unprecedented view of the planet]... was by no means one of those vague conjectures that are sometimes unduly applauded... He relied on the analogy of terrestrial phenomena to those exhibited by what he calls a terrella , or artificial spherical magnet. ...Gilbert was also one of our earliest Copernicans, at least as to

1674-435: The effects of cutting a spherical lodestone (which he calls a terrella ) through the poles and equator and the direction of attraction at different points. Magnets act at a distance but the force has no permanent presence and is not hindered like light. Materials including gold, silver and diamonds are not affected by magnets, nor can one produce perpetual motion . The Earth's normal magnetism. He proposes (incorrectly) that

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1728-466: The following two statements. The first was repeated in three of his works, namely In the Advancement of Learning (1605), Novum Organum (1620), and De Augmentis (1623). The more severe second statement is from History of Heavy and Light Bodies published after Bacon's death. The Alchemists have made a philosophy out of a few experiments of the furnace and Gilbert our countryman hath made

1782-479: The gradual identification of iron ores. The south pole of a lodestone points to the north pole of the Earth and vice versa as the terrestrial globe is magnetic. Distinction between electricity and magnetism. An amber stick when rubbed affects a rotating needle made of any type of metal (a versorium ) and attracts paper, leaves and even water. But electricity is different from heat and to magnetism which only attracts iron-bearing materials (he calls it coition). He shows

1836-420: The idea of magnetic attraction to the planets. Peter of Maricourt Peregrinus's text on the magnet is entitled in many of the manuscripts of it Epistola Petri Peregrini de Maricourt ad Sygerum de Foucaucourt, militem, de magnete ("Letter of Peter Peregrinus of Maricourt to Sygerus of Foucaucourt, Soldier, on the Magnet") but it is more commonly known by its short title, Epistola de magnete ("Letter on

1890-463: The moon attracted the water, but that “subterranean spirits and humors, rising in sympathy with the moon, cause the sea also to rise and flow to the shores and up rivers”. It appears that an idea, presented in some such way as this, was more readily received than a plain statement. This so-called philosophical method was, in fact, very generally applied, and Kepler , who shared Galileo’s admiration for Gilbert’s work, adopted it in his own attempt to extend

1944-480: The moon, and the moon within certain limits, the earth; not so as to make the bodies come together, as magnetic bodies do, but so that they may go on in a continuous course." Though this phraseology is capable of representing a good deal of the truth, it does not appear to have been connected... with any very definite notions of mechanical action in detail. Gilbert died on 30 November 1603 in London. His cause of death

1998-408: The most subtle fifth essence, or in vacuity – how shall the stars keep their places in the mighty swirl of these enormous spheres composed of a substance of which no one knows aught?" The English word "electricity" was first used in 1646 by Sir Thomas Browne , derived from Gilbert's 1600 Neo-Latin electricus , meaning "like amber ". The term had been in use since the 13th century, but Gilbert

2052-538: The poles of the compasses. He also describes the laws of magnetic attraction and repulsion . The letters also contain a description of an experiment with a repaired magnet, as well as a number of compasses, one of which "you will be able to direct your steps to cities and islands and to any place whatever in the world." Indeed, the increasing perfection of magnetic compasses during the thirteenth century allowed navigators such as Vandino and Ugolino Vivaldi to strike out on voyages to unknown lands. The Epistola de magnete

2106-426: The relatively tiny sphere of the Earth. He states, "How far away from the earth are those remotest of stars: they are beyond the reach of eye, or man's devices, or man's thought. What an absurdity is this motion (of spheres)." He also argues for the extreme variability of the distance to the various heavenly bodies and states that situated "in thinnest aether, or in the most subtle fifth essence, or in vacuity – how shall

2160-486: The rotation of the earth; and with his usual sagacity inferred, before the invention of the telescope, that there are a multitude of fixed stars beyond the reach of our vision. Walter William Bryant of the Royal Observatory, Greenwich, wrote in his book Kepler (1920): When Gilbert of Colchester, in his “New Philosophy,” founded on his researches in magnetism, was dealing with tides, he did not suggest that

2214-476: The same thing. For evidence, he (incorrectly) pointed out that, while electrical attraction disappeared with heat, magnetic attraction did not (although it is proven that magnetism does in fact become damaged and weakened with heat). Hans Christian Ørsted and James Clerk Maxwell showed that both effects were aspects of a single force: electromagnetism. Maxwell surmised this in his A Treatise on Electricity and Magnetism after much analysis. Gilbert's magnetism

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2268-558: The science [of magnetism], so fully examined, indeed, that even at this day we have little to add to them. Historian Henry Hallam wrote of Gilbert in his Introduction to the Literature of Europe in the Fifteenth, Sixteenth, and Seventeenth Centuries (1848): The year 1600 was the first in which England produced a remarkable work in physical science; but this was one sufficient to raise a lasting reputation to its author. Gilbert,

2322-423: The siege of Lucera , August 8, 1269"), which might indicate that Peregrinus was in the army of Charles , duke of Anjou and king of Sicily, who in 1269 laid siege to the city of Lucera. However, given that only one manuscript attests this, the evidence is weak. There is no indication of why Peter received the sobriquet Peregrinus (or "pilgrim"), but it suggests that he may have been either a pilgrim at one point or

2376-655: The stars keep their places in the mighty swirl of these enormous spheres composed of a substance of which no one knows aught?". De Magnete was influential because of the inherent interest of its subject matter, but also for the rigorous way in which Gilbert described his experiments and his rejection of ancient theories of magnetism. Gilbert nevertheless acknowledged his debt to Peter of Maricourt and incorporated this 13th-century scientist's experiments on magnetism into his own treatise. William Gilbert (astronomer) William Gilbert ( / ˈ ɡ ɪ l b ər t / ; 24 May 1544? – 30 November 1603), also known as Gilberd ,

2430-468: The whole universe is the motion of the primum mobile ." He rejects the idea of a sphere of the fixed stars for which no proof has been offered and leaves aside the question of other movements of the Earth but "infers not with mere probability, but with certainty the diurnal revolution of the earth." He states that "the cause of the diurnal motion are to be found in the magnetic energy and the alliance of bodies" but offers no further guidance. The inclination of

2484-473: The world. It is the more remarkable, because it preceded the Novum Organum of Bacon, in which the inductive method of philosophizing was first explained. William Whewell writes in his History of the Inductive Sciences (1837/1859): Gilbert... repeatedly asserts the paramount value of experiments. He himself, no doubt, acted up to his own precepts; for his work contains all the fundamental facts of

2538-508: Was Elizabeth I 's own physician from 1601 until her death in 1603, and James VI and I renewed his appointment. His primary scientific work – much inspired by earlier works of Robert Norman – was De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure ( On the Magnet and Magnetic Bodies, and on the Great Magnet the Earth ) published in 1600. In this work, he describes many of his experiments with his model Earth called

2592-594: Was an English physician, physicist and natural philosopher . He passionately rejected both the prevailing Aristotelian philosophy and the Scholastic method of university teaching. He is remembered today largely for his book De Magnete (1600). A unit of magnetomotive force , also known as magnetic potential , was named the Gilbert in his honour; it has now been superseded by the Ampere-turn . Gilbert

2646-473: Was an especially hard form of water, formed from compressed ice: Lucid gems are made of water; just as Crystal, which has been concreted from clear water, not always by a very great cold, as some used to judge, and by very hard frost, but sometimes by a less severe one, the nature of the soil fashioning it, the humour or juices being shut up in definite cavities, in the way in which spars are produced in mines. Gilbert argued that electricity and magnetism were not

2700-533: Was born in Colchester to Jerome Gilberd, a borough recorder . He was educated at St John's College, Cambridge . After gaining his MD from Cambridge in 1569, and a short spell as bursar of St John's College, he left to practice medicine in London, and he travelled on the continent. In 1573, he was elected a Fellow of the Royal College of Physicians . In 1600, he was elected President of the college. He

2754-704: Was full of defects; corrected editions were published by Timoteo Bertelli (in Bulletino di bibliografia e di storia delle scienze matematiche e fisiche pubblicata da B. Boncampagni, 1 (1868), 70–80) and G. Hellmann ( Rara magnetica 1269-1599 [Neudrucke von Schriften und Karten über Meteorologie und Erdmagnetismus, 10], [Berlin, 1898]) . The modern critical edition was prepared by Loris Sturlese and appears in Petrus Peregrinus de Maricourt, Opera (Pisa, 1995), pp. 63–89. A translation into English has been made by Silvanus P. Thompson ("Epistle of Peter Peregrinus of Maricourt, to Sygerus of Foucaucourt, Soldier, concerning

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2808-452: Was published in 1543) (see external reference below). Gilbert made the first attempt to map the surface markings on the moon in the 1590s. His chart, made without the use of a telescope, showed outlines of dark and light patches on the moon's face. Contrary to most of his contemporaries, Gilbert believed that the light spots on the moon were water, and the dark spots were land. Besides Gilbert's De Magnete , there appeared at Amsterdam in 1651

2862-591: Was the first to use it to mean "like amber in its attractive properties". He recognized that friction with these objects removed a so-called "effluvium", which would cause the attraction effect in returning to the object, though he did not realize that this substance ( electric charge ) was universal to all materials. The electric effluvia differ much from air, and as air is the earth's effluvium, so electric bodies have their own distinctive effluvia; and each peculiar effluvium has its own individual power of leading to union, its own movement to its origin, to its fount, and to

2916-445: Was the invisible force that many other natural philosophers seized upon, incorrectly, as governing the motions that they observed. While not attributing magnetism to attraction among the stars, Gilbert pointed out the motion of the skies was due to Earth's rotation, and not the rotation of the spheres, 20 years before Galileo (but 57 years after Copernicus , who stated it openly in his work De revolutionibus orbium coelestium , which

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