Sketching the History of Classical Electromagnetism (Optics, Magnetism, Electricity, Electromagnetism)

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Anti- quity	Many things are known about optics: the rectilinearity of light rays; the law of reflection; transparency of materials; that rays passing obliquely from less dense to more dense medium is refracted toward the perpendicular of the interface; general laws for the relationship between the apparent location of an object in reflections and refractions; the existence of metal mirrors (glass mirrors being a 19th century invention).
ca 300 BC	Euclid of Alexandria (ca 325 BC - ca 265 BC) writes, among many other works, Optics, dealing with vision theory and perspective. Convex lenses in existence at Carthage.
1st cent BC	Chinese fortune tellers begin using loadstone to construct their divining boards, eventually leading to the first compasses. (Mentioned in Wang Ch'ung's Discourses weighed in the balance of 83 B.C.)
1st cent	South-pointing divining boards become common in China.
2nd cent	Hero of Alexandria writes on the topics of mirrors and light. Claudius Ptolemy (ca 85 - ca 165) writes Optics, an experimental and mathematical treatment, extending earlier work on reflection by Euclid and Hero, including both concave and convex spherical and cylindrical mirrors, and doing original research on refraction.
ca 271	True compasses come into use by this date in China.
6th cent	(China) Discovery that loadstones could be used to magnetize small iron needles.
11th cent	Abu Ali al-Hasan ibn al-Haitam (Alhazen) (965-1039) writes Kitab al-manazir (translated into Latin as Opticae thesaurus Alhazeni in 1270) on optics, dealing with reflection, refraction, lenses, parabolic and spherical mirrors, aberration and atmospheric refraction. He adapts the mathematical extramission theory (which he rejects) to the intramission framework. (China) Iron magnetized by heating it to red hot temperatures and cooling while in south-north orientation.	al-Haitam (Alhazen)
1086	Shen Kua's Dream Pool Essays make the first reference to compasses used in navigation.
1150s	Earliest explicit reference to magnets per se, in Roman d'Enéas. (see reference)
1190s	Alexander Neckam's De naturis rerum contains the first western reference to compasses used for navigation, and it had by this time been in common use.
13th cent	Robert Grosseteste (1168-1253) writes De Iride and De Luce on optics and light, experimenting with both lenses and mirrors. Roger Bacon (1214-1294) writes many works on the nature of light and optics (and some on magnetism). Greatly furthering the work of Grosseteste and Alhazen, and having access to and mastery of the major literature on optics, Bacon develops a unified framework for the understanding of light and geometric optics. Pierre de Maricourt, a.k.a. Petri Pergrinus (fl. 1269) writes Letter on the magnet of Peter the Pilgrim of Maricourt to Sygerus of Foucaucourt, Soldier, the first western analysis of polar magnets and compasses. He demonstrates in France the existence and fundamental role of two poles of a magnet by tracing the directions of a needle laid on to a natural magnet. Witelo (d after 1281) writes Perspectiva around 1270, treating geometric optics, including reflection and refraction. He also reproduces the data given by Ptolemy on optics, though was unable to generalize or extend the study. John Pecham's (d. 1292) work on optics and light. Theodoric of Freiberg (ca 1250 - ca 1310), working with prisms and transparent crystalline spheres, formulates a sophisticated theory of refraction in raindrops which is close to the modern understanding, though it did not become very well known. (Descartes presents a nearly identical theory roughly 450 years later.) Eyeglasses, convex lenses for the far-sighted, first invented in or near Florence (as early as the 1270s or as late as the late 1280s - concave lenses for the near-sighted appearing in the late 15th century).
16th cent	Girolamo Cardano (1501-1576) elaborates the difference between amber and loadstone.
1558	Giambattista Della Porta (1535-1615) publishes his major work, Magia naturalis, analyzing, among many other things, magnetism.
1600	William Gilbert (1544-1603), after 18 years of experiments with magnetic and electrical materials, finishes his book De Magnete. The work included: the first major classification of electric and non-electric materials; gives the name "electric" to the substance behind electrical phenomena; a comarative study of electric and magnetic field effects; the relation of moisture and electrification; showing that electrification effects metals, liquids and smoke; noting that electrics were the attractive agents (as opposed to the air between objects); that heating dispelled the attractive power of electrics; and showing the earth to be a magnet.	William Gilbert
1606	Della Porta first describes the heating effects of light rays.
1618	April 2nd, Francesco Maria Grimaldi discovers diffraction patterns of light and becomes convinced that light is a wave-like phenomenon. The theory is given little attention.
1621	Willebrord van Roijen Snell (1580-1626) experimentally determines the law of angles of incidence and reflection for light and for refraction between two media.
1629	Nicolo Cabeo (1586-1650) publishes his observations on electrical repulsion, noting that attracting substances may later repel one another after making contact.
1630	Vincenzo Cascariolo discovers a substance that shines in the dark after exposure to sunslight, the so-called Bologna phosphorus.
1637	René Descartes publishes his Dioptics and On Meteors as appendices to his Discourse on a Method, detailing a theory of refraction and going over a theory of rainbows which, while containing nothing essentially new, encouraged experimental exploration of the subject.
1644	Descartes' Principia philosophiae, describing magnetism as the result of the mechanical motion of channel particles and their displacements, and proposing the absence of both void and action at a distance.
1646	Thomas Browne (1605-1682) coins the term "electricity" in his Pseudodoia Epidemica.
1657	Pierre de Fermat (1601-1665) formulates the principle of least time for understanding the way in which light rays move.	Pierre de Fermat
1660	Otto von Guericke (1602-1686) builds the first electrical machine, a rotating frictional generator.
1661	Fermat is able to apply his principle of least time to understand the refractive indices of different materials.
1664	Robert Hooke (see also: Robert Hooke) (1635-1703) puts forth a wave theory of light in his Micrographia, considering light to be a very high speed rectilinear propagation of longitudinal vibrations of a medium in which individual wavelets spherically spread. He also introduces wave-front analysis, the nation of a material's optical density and a theory of color.
1665	Francesco Maria Grimaldi's Prysico-mathesis de lumine coloribus et iride describes experiments with diffraction of light and states his wave theory of light.
1669	Erasmus Bartholin publishes A Study of Iceland Spar, about his discovery of double refraction.
1671	Isaac Newton presents his observations on color and suggests color to be a property of light rays.
1672	Newton presents a corrected account of Huygen's discover of polarization phenomena.
1675	Robert Boyle (1627-91) writes Experiments and Notes about the Mechanical Origine or Production of Electricity. Electrical attraction, it was written, was "a Material Effluvium issuing from and returning to, the Electrical Body."
1676	Ole Christensen Rømer (1644-1710) demonstrates the finite speed of light via observations of the eclipses of the satellites of Jupiter. While not calculating a speed for light, he estimates the Sun-Earth transit time for light to travel as roughly 11 minutes.	Chirstiaan Huyghens
1677	Christiaan Huyghens (1629-95) extends the wave theory of light in his work Treatise on Light, unpublished until 1690.
1687	Newton (1642-1727) notes magnetism to be a non-universal force and derives an inverse cubed law for two poles of a magnet.
1690	Publication of Huyghens' work Treatise on Light. This work includes a wave theory of light with a finite speed, giving the first numerical quote for the speed of light to be 2.3 x 108 m/s (often mistakenly attributed to Rømer). The work also gives explanations of wave propagation, reflection, refraction, double-refration, and polarization.
1699	Nicolas Malebranche (1638-1715) proposes monochromatic light to depend on periodic vibrations and that brightness is in proportion to their amplitude.
1704	Newton's research on light culminates in the publication of his Optics, describing light both in terms of wave theory and his corpuscular theory.
1709	Francis Hauksbee's (1666-1713) Physico-Mechanical Experiments on Various Subjects.
1728	James Bradley (1693-1762) discovers the phenomenon of steller aberration, confirming earlier suggestions by Rømer that the speed of light is finite.
1729	Stephen Gray (ca 1670-1736) shows static electricity to be transported via substances, especially metals.
1733	Charles-Francois de Cisternai du Fay (1698-1739) discovers that electric charges are of two types and that like charges repell while unlike charges attract.
1745	Ewald Kleist (1700-1748) invents the Leyden jar for storing electric charge.
1746	William Watson (1715-89) suggests conservation of electric charge. Jean Antoine Nollet's Essai sur l'electricité des corps.
1747	Benjamin Franklin (1706-90) proposes that electricity be modeled by a single fluid with two states of electrification, materials have more or less of a normal amount of electric fluid, independently proposing conservation of electric charge, and introducing the convention of describing the two types of charges as positive and negative. Watson passes electrical charge along a two mile long wire.
1750	John Michell (1724-93) demonstrates that the action of a magnet on another can be deduced from an inverse square law of force between individual poles of the magnet, published in his work, A Treatise on Artificial Magnets.
1759	Franz Ulrich Theodosius Aepinus (1724-1802) publishes An Attempt at a Theory of Electricity and Magnetism, the first book applying mathematical techniques to the subject.
1764	Johannes Wilcke invents the electrophorus, a device which can produce relatively large amounts of electric charge easily and repeatedly. (See Links)
1766	Joseph Priestley (1733-1804) deduces the inverse square law for electric charges using the results of experiments showing the absence of electrical effects inside a charged hollow conducting sphere.
1772	Henry Cavendish publishes, "An Attempt to Explain some of the Principal Phenomena of Electricity, by Means of an Elastic Fluid."
1775	Alessandro Guiseppe Antonio Anastasio Volta (1745-1827) invents an electrometer, a plate condenser and the electrophorus.	Charles de Coulomb
1777	Charles Augustin de Coulomb's (1736-1806) research sets a new direction in research into electricity and magnetism.
early 1780s	Luigi Galvani (1737-98) uses the response of animal tissue to begin studies of electrical currents produced by chemical action rather than from static electricity. The mechanical response of animal tissue to contact with two dissimilar metals is now known as galvanism.
1785	Coulomb independently invents the torsion balance to confirm the inverse square law of electric charges. He also verifies Michell's law of force for magnets and also suggests that it might be impossible to separate two poles of a magnet without creating two more poles on each part of the magnet.
1799	Volta shows that galvanism is not of animal origin but occurred whenever a moist substance is placed between two metals. This discovery eventually leads to the "Volta pile" a year later, the first electric batteries.
1800	Volta writes a paper on electricity by contact.
1801	Thomas Young's (1773-1829) work on interference revives interest in the wave theory of light. He also accounts for the recently discovered phenomenon of light polarization by suggesting that light is a vibration in the aether transverse to the direction of propagation. Johann Georg von Soldner (1776-1833) makes a calculation for the deflection of light by the sun assuming a finite speed of light corpuscles and a non-zero mass. (The result, 0.85 arc-sec, was rederived independently by Cavendish and Einstein (1911), but went unnoticed until 1921. )
1807	H Davy's lecture, "On Some Chemical Agents of Electricity," drawing close the possible relationships of chemical and electrical forces.
1812	Simeon-Denis Poisson (1781-1840) formulates the concept of macroscopic charge neutrality as a natural state of matter and describes electrification as the separation of the two kinds of electricity. He also points out the usefulness of a potential function for electrical systems.
1813	Measurements of specific heat of air as a function of pressure by Delarache and Bérard.
1814	Augustin Jean Fresnel (1788-1827) independently discovers the interference phenomena of light and explains its existence in terms of wave theory.	André Marie Ampère
1817	Fresnel predicts a dragging effect on light in the aether.
1818	Fresnel's essay on optics and the aether.
1820	(July 21) Hans Christian Oersted (1777-1851) notes the deflection of a magnetic compass needle caused by an electric current after giving a lecture demonstration. Oersted then demonstrates that the effect is reciprocal.This initiates the unification program of electricity and magnetism. July 27, André Marie Ampère (1775-1836) confirms Oersted's results and presents extensive experimental results to the French Academy of Science. He models magnets in terms of molecular electric currents. His formulation inaugurates the study of electrodynamics independent of electrostatics. Fall, Jean-Baptiste Biot (1774-1862) and Felix Savart (1792-1841) deduce the formula for the strength of the magnitec effect produced by a short segment of current carrying wire.
1825	Ampère 's memoirs are published on his research into electrodynamics.	By the 1820's, the concept of a luminiferous ether comes into common use by physicists and engineers.
1827	Georg Simon Ohm (1789-1854) formulates the relationship between current to electromotive force and electrical resistance.
1828	George Green (1793-1841) introduces the notion of potential and formulates what is now called Green's Theorem relating the surface and volume distributions of charge. (The work goes unnoticed until 1846.)
1831	Michael Faraday (1791-1867) begins his investigations into electromagnetism.
1832	Gauss (1777-1855) independently states Green's Theorem without proof. He also reformulates Coulomb's law in a more general form, and establishes experimental methods for measuring magnetic intensities.	Carl Friedrich Gauss
1835	Gauss formulates separate electrostatic and electrodynamical laws, including "Gauss's law." All of it remains unpublished until 1867.
1838	Faraday explains electromagnetic induction, electrochemistry and formulates his notion of lines of force, also criticizing action-at-a-distance theories. Wilhelm Eduard Weber (1804-91) and Gauss apply potential theory to the magnetism of the earth.
1839	The potential theory for magnetism developed by Weber and Gauss extented to all inverse-squared phenomena.
1842	William Thomson (Lord Kelvin, 1824-1907) writes a paper, "On the uniform motion of heat and its connection with the mathematical theory of electricity," based on the ideas of Fourier. The analogy allows him to formulate a continuity equation of electricity, implying a conservation of electric flux.
1845 to 1850	Michael Faraday introduces the idea of "contiguous magnetic action" as a local interaction, instead of the idea of instantaneous action at a distance, using concepts now known as fields. He also estabishes a connection between light and electrodynamics by showing that the transverse polarization direction of a light beam was rotated about the axis of propagation by a strong magnetic field (today known as "Faraday rotation"). G T Fechner proposes a connection between Ampère's law and Faraday's law in order to explain Lenz's law.
1846	Weber proposes a synthesis of electrostatics, electrodynamics and induction using the idea that electric currents are moing charged particles. The interactions are instantaneous forces. Weber's theory contains a limiting velocity of electromagnetic origin with the value Sqrt(2) * c. William Robert Grove's (1811-1896) Correlation of physical forces The partial-drag theory of George Gabriel Stokes (1819-1903) is revived for the explanation of stellar aberration.
1849	A.H.L. Fizeau begins experiments to determine the speed of light.
1851	Fizeau's interferometry experiment confirming Fresnel's theoretical results.
1852	Stokes names and explains the phenomena of fluorescence.
1854	Bernhard Riemann (1826-66) makes unpublished conjectures about an 'investigation of the connection between electricity, galvanism, light and gravity.'
1855	Weber and R Kohlrausch determine a limiting velocity which turns up in Weber's electrodynamic theory, and that it's value is about 439,450 km/s.	James Clerk Maxwell
1855 to 1868	James Clerk Maxwell (1831-79) completes his formulation of the field equations of electromagnetism. He established, among many things, the connection between the speed of propagation of an electromagnetic wave and the speed of light, and establishing the theoretical understanding of light.
1858	Riemann generalizes Weber's unification program and derives his results via a solution to a wave function of a electrodynamical potential (finding the speed of propagation, correctly, to be c). He claimed to have found the connection between electricity and optics. (Results published postumously in 1867.)
1861	Riemann uses Lagrange's theorem to deal with velocity-dependent electrical accelerations. Gustav Robert Kirchhoff (1824-1887) formulates the model of the black body.	Bernhard Riemann
1863	John Tyndall's Heat Considered as a Mode of Motion.
1864	Maxwell publishes A Dynamical Theory of the Electromagnetic Field, his first publication to make use of his mathematical theory of fields.
1865	Maxwell's A Dynamical Theory of the Electromagnetic Field, formulating an electrodynamical formulation of wave propagation using Lagrangian and Hamiltonian techniques, obtaining the theoretical possibility of generating electromagnetic radiation. (The derivation is independent of the microscopic structures which may underlie such phenomena.)
1870	Hermann Ludwig Ferdinand von Helmholtz (1821-94) developes a theory of electricity and shows Weber's theories to be inconsistent with the conservation of energy.
1873	The first edition of Maxwell's Treatise on Electricity and Magnetism is published.
1874	George J Stoney estimates the charge of an electron to be about 10-20 Coulombs and introduces the term "electron."	Hendrik Lorentz
1875	Hendrik Antoon Lorentz (1853-1928), in his doctoral thesis, derives the phenomena of reflection and refraction in terms of Maxwell's theory. W Crookes performs experiments on cathode rays.
1879	Maxwell suggests that an earth-based experiment to detect possible aether drifts could be performed, but that it would not be sensitive enough.
1881	A.A. Michelson begins his interferometry experiments to detect a luminiferous aether. Joseph John Thomson's (1856-1940) paper, "On the electric and magnetic effects produced by the motion of electrified bodies" explores inertial effects due to displacement currents.
1884	Heinrich Rudolf Hertz (1857-94) develops a reformulation of electrodynamics and shows his and Helmholtz's theories both amount to Maxwell's theory. John Henry Poynting (1852-1914) establishes a principle of electromagnetic radiation energy which can be localized and flow (the first such energy localization principle established); not confined to existing only in conductors, but throughout space, independent of matter.
1885 to 1887	Oliver Heaviside (1850-1925) writes Electromagnetic induction and its propagation over the course of two years, re-expressing Maxwell's results in 3 (complex) vector form, giving it much of its modern form and collecting together the basic set of equations from which electromagnetic theory may be derived (often called "Maxwell's equations"). In the process, He invents the modern vector calculus notation, including the gradient, divergence and curl of a vector.	Oliver Heaviside
1887	Heinrich Rudolf Hertz experimentally produces electromagnetic radiation with radio waves in the GHz range, also discovering the photoelectric effect and predicting that gravitation would also have a finite speed of propagation. W Voight, working through an analysis of Doppler effects using an elastic model of the luminiferous aether to describe optical properties, produces a set of relations between space and time intervals which are later rediscovered independently by Lorentz and now knows as the "Lorentz equations" (first so-called by Poincaré in 1904).
1889	George Francis FitzGerald (1851-1901) suggests that bodies contract in the direction of motion against the luminiferous aether by an amount which would account for the null results coming from the Michelson-Morley experiments on aether motion. (A more detailed calculation is performed independently by Lorentz in 1895.) FitzGerald also suggests that the speed of light is an upper bound on any possible speed. (This suggestion reappears in 1900 by Lorentz, in 1904 by Poincaré, and again in 1905 by Einstein.) John William Strutt (Lord Rayleigh, 1842-1919) presents a model for radiation in terms of wave propagation. Heaviside's "On the electromagnetic effects due to the motion of electrification through a dielectric," proposes part of inertial mass to be electromagnetic in origin and includes dependencies on higher-order terms in (v/c).
1890	Hertz publishes his memoirs on electrodynamics, simplifying the form of the electromagnetic equations, replacing all potentials by field strengths, and deduces Ohm's, Kirchoff's and Coulomb's laws.	JJ Thomson
1892 to 1904	Lorentz completes the description of electrodynamics by clearly separating electricity and electrodynamic fields and formulating the equations for charged particles in motion.
1893	Wilhelm Carl Werner Otto Fritz Franz Wien (1864-1928) gives his displacement law of blackbody radiation.
1896	Wien theoretically derives the radiation distribution law. Discovery of X-rays and Becquerel radiation. Discovery of the Zeeman effect.
1897	JJ Thomson experimentally determines the charge-to-mass ratio, e/m, of electrons.
1898	Jules Henri Poincaré (1854-1912) suggests that a complete measurement theory must formulate a notion of distant synchronization and discusses its relevance to the apparent constancy of the speed of light.
1899	Lorentz refines the transformation laws, formulating the notion of local time and local coordinate systems in electrodynamics. Thomson and Philipp Lenard begin experimental investigations of photoelectric radiation.	Hermann Minkowski
1900	Wien's "On the possibility of an electromagnetic foundation of mechanics." Poincaré's paper "The theory of Lorentz and the principle of reaction," showing electromagnetic radiation to have a momentum proportional to a field's Poynting vector, and that the momentum of a recoiling body to be vE/c2. Max Karl Ernst Ludwig Planck (1858-1947), studying blackbody radiation derives the correct radiation spectrum for blackbodies. Planck proposes the constant, h (Planck's constant), as a quantum of action in phase space.
1902	Max Abraham's (1875-1922) "The dynamics of electrons," also introducing the concept of electromagnetic momentum. Walter Kaufmann (1871-1947) performs experiments on the deflection of electrons by electric and magnetic fields and a determination of the ration e/m; In a second paper, he concludes that the mass of an electron is purely electromagnetic in origin.
1903	Abraham's "Principles of the dynamics of electrons," attempts to show, among other things, the electromagnetic foundation of mechanics.
1904	Poincaré uses light signals as a functional technique to establish distant synchronization in application to Lorentz's electron theory, also putting forth the first formulation of a principle of electrodynamic relativity.
1905	Albert Einstein (1879-1955) analyzes the phenomena of the photoelectric effect and theorizes that light may be taken to be made up of vast amounts of packets of electromagnetic radiation in discrete units. Einstein publishes several papers drawing out the symmetries of Maxwell, Hertz and Lorentz's electromagnetic theory, the underlying connection in measurement theory and the status of the electromagnetic aether.
1907	Hermann Minkowski (1864-1909), through considerations of the group properties of the equations of electrodynamics, reinterprets Einstein's relativity theory as a kind of geometry of spacetime, considered as a single medium. Planck gives a corrected derivation of the mass-energy relation using Poincaré's radiation momentum.
1908	Gilbert N Lewis (1875-1946) publishes "A revision of the fundamental laws of matter and energy," deriving dE = c2dm from considerations of radiation pressure.
1933	Experiments by Patrick Blackett (1897-1974) and Giuseppe Occhialini (1907-93) on pair production demonstrate the complete annihilation of matter into electromagnetic energy.

Sources:

Bellone, Enrico, A World on Paper: Studies on the Second Scientific Revolution, 1980, ISBN 0-262-02147-1, QC7.B4313 Brush, Stephen G, Statistical Physics and the Atomic Theory of Matter From Boyle and Newton to Landau and Onsager Doughty, Noel A, Lagrangian Interaction: An Introduction to Relativistic Symmetry in Electrodynamics & Gravitation, 1990, ISBN 0-201-41625-5 Gans, Paul J, The Medieval Technology Pages: Magnets, 1998 Jammer, Max, Concepts of Mass in Classical and Modern Physics, 1961, ISBN 0-486-29998-8 Lindberg, David C, (ed.) Science in the Middle Ages, 1978 Stauffer, Robert C, "Speculation and Experiment in the Background of Oersted's Discovery of Electromagnetism," Isis, 48, pp 35-50. Nobel Prizes in Physics The great MacTutor History of Mathematics Archive

Links:

Electromagnetism and Classical Optics Electrophorus and Accessories A Timeline of Electricity and Magnetism

Notes:

The early history of optics needs some work, ancient through medieval times. Static electricity needs some fleshing out between 1200 and 1700. The shift in theory in the last part of the 19th and early 20th century needs some more. work, including Lagrangian/Hamiltonian, manifold and group theory. 20th century advances in purely classical theory needs to be filled out. There's a hole in what I've found about fluroesence.