Editing William Gilbert (physicist) (section)

== Life and work ==
[[File:Tymperleys, 15th Century house in Colchester - geograph.org.uk - 189178.jpg|thumb|upright=1.25|right|Timperleys, the 15th-century home of the Gilbert family in Colchester.]]
[[File:Willian Gilberd, M.D., demonstrating his experiments to queen Elizabeth A. Auckland Hunt.jpg|thumb|
William Gilbert M.D. demonstrating his experiments before Queen Elizabeth I (painting by A. Auckland Hunt).
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Gilbert was born in Colchester to Jerome Gilberd, a borough [[Recorder (judge)|recorder]]. He was educated at [[St John's College, Cambridge]].<ref>{{acad|id=GLBT558W|name=Gilbert, William}}</ref> After gaining his [[Doctor of Medicine|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.<ref name=Mottelay>Mottelay, P. Fleury (1893). "Biographical memoir". In {{harvnb|Gilbert|1893|pp=ix–xxvii}}</ref> He was [[Elizabeth I of England|Elizabeth I]]'s own physician from 1601 until her death in 1603, and [[James I of England|James VI and I]] renewed his appointment.<ref name=Pumfrey>{{cite book |last=Pumfrey |first=Stephen |year=2002 |title=Latitude & the Magnetic Earth |publisher=Icon Books |isbn=1-84046-486-0}}</ref>{{rp|30}}

His primary scientific work – much inspired by earlier works of [[Robert Norman]]<ref>{{cite journal |last=Zilsel |first=Edgar |title=The Origin of William Gilbert's Scientific Method |journal=Journal of the History of Ideas |volume=2 |issue=1 |pages=1–32 |year=1941 |jstor=2707279 |url=http://philoscience.unibe.ch/documents/MaterialHS11/PSWissRev/Zilsel1941.pdf |url-status=dead |archive-url=https://web.archive.org/web/20140714194058/http://philoscience.unibe.ch/documents/MaterialHS11/PSWissRev/Zilsel1941.pdf |archive-date=14 July 2014 |doi=10.2307/2707279 }}</ref><ref>Roller, Duane H D (1959) ''The De Magnete of William Gilbert'', Amsterdam.</ref> – was ''[[De Magnete|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 the [[terrella]]. From these experiments, he concluded that [[Earth's magnetic field|Earth]] was itself [[magnetic]], and that this was the reason why [[compass]]es 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 a new magnet with north and south poles.

In [[De Magnete#Book 6, Chapter III: Of the Daily Magnetic Rotation of the Globes|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 the most subtle fifth essence, or in vacuity&nbsp;– 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 [[Thomas Browne|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 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.<ref name="Heathcote">{{cite journal |last=Heathcote |first=Niels H. de V. |doi=10.1080/00033796700203316 |volume=23 |issue=4 |page=261 |title=The early meaning of ''electricity'': Some ''Pseudodoxia Epidemica'' – I |journal=[[Annals of Science]] |date=1967}}</ref>

{{blockquote|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 the body emitting the effluvium.|{{harvnb|Gilbert|1600}}<ref>{{harvnb|Gilbert|1893|p=92}}</ref>}}

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]]''.<ref>{{harvnb|Gilbert|1893|p=79}}</ref>

Like other people of his day, he believed that crystal (clear [[quartz]]) was an especially hard form of water, formed from compressed ice:

{{blockquote|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.|''[[De Magnete]]'', English translation by [[Silvanus Phillips Thompson]], 1900}}

Gilbert argued that electricity and magnetism were not 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]] 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 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.<ref>Bochenski, Leslie (April 1996) [http://uias.astro.illinois.edu/s-m/sm-apr-96.html "A Short History of Lunar Cartography"] {{webarchive|url=https://web.archive.org/web/20100803073221/http://uias.astro.illinois.edu/s-m/sm-apr-96.html |date=3 August 2010 }}. University of Illinois Astronomical Society</ref>

[[File:Demundo.png|thumb|right|Diagram of the universe appearing on p202 of ''De Mundo'']]
Besides Gilbert's ''De Magnete'', there appeared at Amsterdam in 1651 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 (chemist)|John Davy]], "this work of Gilbert's, which is so little known, 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 [[Francis Bacon|Bacon]], his opposition to the philosophy of [[Scholasticism|the schools]] was more searching and particular, and at the same time probably little less efficient." In the opinion of [[John Robison (physicist)|Prof. John Robison]], ''De Mundo'' consists of an attempt to establish a new system of natural philosophy upon the ruins of the Aristotelian doctrine.<ref name=Mottelay/>

[[William Whewell]] says in his ''History of the Inductive Sciences'' (1859):<ref>Whewell, William (1859) ''History of the Inductive Sciences''. D. Appleton.  [https://books.google.com/books?id=vdQyAQAAMAAJ& Vol. 1]. p. 394</ref>

<blockquote>
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.<ref>Gilbert, William ''De Magnete'', Book 6, Ch. 6,7</ref> Gilbert died in 1603, and in his posthumous work (''De Mundo nostro Sublunari Philosophia nova'', 1631) we have already a more distinct statement of the attraction of one body by another.<ref>Gilbert, William ''De Mundo'', Book 2, Ch. 19</ref> "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, 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.<ref>{{harvnb|Gilbert|1893|p=346}}</ref>
</blockquote>

Gilbert died on 30 November 1603 in London.  His cause of death is thought to have been the [[bubonic plague]].<ref>[http://www.magnet.fsu.edu/education/tutorials/pioneers/gilbert.html William Gilbert] {{Webarchive|url=https://web.archive.org/web/20070426151912/http://www.magnet.fsu.edu/education/tutorials/pioneers/gilbert.html |date=26 April 2007 }}. National High Magnetic Field Laboratory</ref><ref>[https://www.bbc.co.uk/history/historic_figures/gilbert_william.shtml William Gilbert (1544–1603)]. BBC</ref>

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.<ref>{{cite web|last1=Ross|first1=David|title=Colchester, Holy Trinity Church {{!}} Historic Essex Guide|url=http://www.britainexpress.com/counties/essex/churches/colchester-holy-trinity.htm|website=Britain Express|access-date=29 October 2016}}</ref>