2637 B.C.
Hoang-ti, founder of the Chinese empire, uses a magnetic chariot
(legend).
600 B.C.
Thales of Miletus (640-546), Greek scientist and philosopher,
discovers attractive power of charged amber.
1269 A.D.
Petrus Peregrinus discovers properties of magnetism and shows that
like poles (his own term) repel and unlike poles attract.
1492
Christopher Columbus
(1451-1506) shows that the declination of a compass needle varies for different parts of
the world.
1600
William Gilbert (1540-1603), English physician and physicist,
publishes De Magnete, six volumes describing the earth as having the properties
of a huge magnet (and thereby explaining the behavior of the compass needle). Gilbert also
coined the word "electricity" from "electron", the Greek word for
amber.
1650
Otto van Guericke (1602-1686), German physicist, builds the first
static machine. Consisting of a large sulphur ball mounted on a shaft, this machine
produced static electricity when a pad was rubbed against the ball as rotated.
1729
Stephen Gray (1696-1736), English electrical experimenter, evolves
the concept of conductors and nonconductors. His theory led to the discovery of electrical
insulation.
1733
Charles François de Cisternay Du Fay (1698-1739) of Paris
discovers that there are only two kinds of electricity - vitreous (positive) and resinous
(negative) - and announces that like charges repel and unlike charges attract.
1745
Pieter van Musschenbroek (1692-1761), Dutch mathematician,
discovers principle of the Leyden jar. wherein charges of static electricity can be built
up and stored.
1747
Benjamin
Franklin (1706-1790), American statesman and philosopher, advances single fluid theory
of electricity, originates "plus" and "minus" designations, and
invents the lightning rod.
1771
Luigi
Galvani (1737-1798), Italian physiologist, discovers that frog's legs contract when
touched at different points by two dissimilar materials which also touch. Galvani advanced
theory of "animal electricity" in 1786.
1785
Charles
Augustin de Coulomb (1736-171806), French physicist, proves the law of inverse
squares, which states that the force exerted between two charged spheres is directly
proportional to the product of their charges and is inversely proportional to the square
distance between them. coulomb also proved that the internal surface of a body
cannot be charged with static electricity.
1800
Alessandro
Volta (1745-1827), Italian physicist, discovers the first practical method of generating electricity.
The voltaic pile (named in his honor) consists of a stack of silver and zinc plats
separated from each other by cloth or paper saturated with a salt solution.
1819
Hans Christian Oersted (1777-1851), Danish physicist, discovers
that a magnetic field is caused by electric current, thus proving that electricity and
magnetism are related.
1820
André Marie
Ampère (1775-1836), French physicist, shows that the forces between currents and
magnets and also between two currents can be determined by assuming that each element of
the circuit exerts a force on a magnetic pole and on every other current element in the
circuit. This discovery established the relationship between electricity and magnetism.
Ampère also developed the solenoid.
1820
Dominique François Jean Arago (1786-1853), French physicist,
discovers that a magnet can be made from an iron or steel bar placed inside a solenoid
through which current is flowing.
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1821
Michael
Faraday (1791-1867), English chemist and physicist, shows that the flow of current in
a wire can cause a magnet to revolve around the wire and that a current-carrying wire
tends to revolve around a fixed magnet.
1823
Thomas Johann Seebeck
(1770-1831), German physicist, discovers that an electric current is produced when two
dissimilar metals are joined and their junction point is heated.
1827
George
Simon Ohm (1787-1854), German physicist, discovers the relation between current,
voltage, and resistance in an electric circuit, now known as Ohm's law, which states that
the electromotive force divided by the rate of current flow through a conductor represents
the resistance of
the conductor.
1831
Joseph Henry
(1797-1878), professor of physics in Albany, N.Y., and Michael Faraday make numerous
electromagnetic discoveries, such as the principle of self-inductance, the transformer,
the generation of electricity by magnetism, the disk dynamo, and many others.
1833
Karl Friedrich
Gauss (1777-1855), German physicist and mathematician, develops an exact mathematical
formula for the magnetic field.
1834
Heinrich Friedrich Emil Lenz (1804-1865), German-Russian physicist,
establishes a method of determining the directions of induced current in a circuit, now
known as Lenz's law.
1840
Samuel F.B.
Morse (1791-1872), American artist and inventor, makes first lead-acid storage cell to
store electrical energy.
1859
Gaston Planté (1834-1899) French inventor, makes first lead-acid
storage cell to store electrical energy.
1865
James Clerk Maxwell
(1831-1879), Scottish physicist, explains in mathematical terms the transmission of
electric and magnetic fields through vacuum.
1875
Alexander Graham Bell
(1847-1922), American inventor, develops the electric telephone.
1879
Thomas Alva
Edison (1847-1931), American inventor, develops a dynamo and the incandescent lamp.
Edison also invented the phonograph, an improved telegraph system, talking pictures, the
alkaline storage battery, and many other electrical devices.
1887
Heinrich Rudolf Hertz (1857-1894), German physicist, discovers that
certain metals give off electric energy when struck by light. Hertz also discovered in
1888 that electricity may be transmitted by electromagnetic waves.
1888
Nicola Tesla (1856-1943), American engineer and inventor, announces
discovery of the principles of the rotating magnetic field, on which the induction motor
is based.
1895
Guglielmo Marconi (1874-1937), Italian inventor, begins experiments
in wireless telegraphy.
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A word of explanation: The reason we stop our
chronology at this point is that by the time of the invention of wireless telegraphy, the
basic principles of electricity had been formulated. Beyond them lies the field of
electronics, a subject outside the scope of this book.
P.S. If you know about interesting and
useful web sites, that might be linked to this page, please let me know about them!
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Resources on Project-Based Instruction 
E-mail me: marinamb@physics.utexas.edu