A Short History of Electricity

8/12/2019 A Short History of Electricity

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A Ridiculously Trite History of

Electricity


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Any discussion of the history of electricity from antiquity

accompanying topics of light and the aether(ether).

We will make three journeys through history:One for electricity

One for light

One for the ether


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Electricit Ma netism

Static

Charges

Moving

Charges

Electromagnetism


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Newton (late 1600s)

ec r c y an agne sm g

Particles

WavesFluids

Fields

Electromagnetic PhenomenaMaxwell (late 1800s)


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The Ether

, , .

e ree s:

How can nothing be something?

.

Ether must fill the heavens


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900 BC - Magnus walks across a field of black stones

which pull the iron nails out of his sandals . This region

becomes known as Magnesia.

600 BC - Thales of Miletos rubs amber with cat fur

1600 - William Gilbert discovers that the earth is agiant magnet explaining how compasses work. He also

discusses static electricity and invents the idea of an

e ec r c u w c s era e y ru ng.


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1729 - Stephen Gray shows that electricity doesn't

have to be made in place by rubbing but can also be

transferred from place to place with conducting wires.

resides on their surfaces.

1733 - Charles Francois du Fay discovers that

electricity comes in two kinds which he calledresinous(-) and vitreous(+).

- e ean- n o ne o e nven s etwo-fluid theory electricity.


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-one-fluid electricity in which one of Nollet's fluids exists

.

the principle of conservation of charge and calls the fluidthat exists and flows ``positive''. This educated guess

ensures that undergraduates will always be confused

about the direction of current flow. He also discovers thate ec r c y can ac a a s ance n s ua ons w ere u

flow makes no sense.


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1748 - Sir William Watson uses an electrostatic

machine and a vacuum pump to make the first

glowing discharge tube. His glass vessel is three feet

and three inches in diameter; the first fluorescent light bul

1752 - Johann Sulzer puts lead and silver together in`` ''

a battery.

1759 - Francis Ulrich Theodore Aepinus shows that

electrical effects are a combination of fluid flow confined

o ma er an ac on a a s ance. e a so scoverscharging by induction.


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1775 - Henry Cavendish invents the idea of capacitance

and resistance (the latter without any way of measuring

current other than the level of personal discomfort).

But being indifferent to fame he is content to wait for his

.

-

with static electricity, then also discovers that the same

twitching can be caused by contact with dissimilar metals.His followers invent another invisible fluid, that

of ``animal electricity'', to describe this effect.


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1785 - Charles Augustin Coulomb uses a torsion

balance to verify that the electric force law is

inverse square. He also proposes a combined

fluid/action-at-a-distance theory with two conducting

.

Force = 1 q1 q24o r


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1793 - Alessandro Volta makes the first batteries.

electricity flowing through the frog legs. In 1800 he

develo s the Voltaic ile dissimilar metals se arated b

wet cardboard) which greatly increases the magnitudeof the effect.

1807 - Humphrey Davy shows that the essential'

gives no effect. He argues that chemical effects are


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1812 - Michael Faraday, a bookbinders apprentice,

scientific assistant. Davy interviews Faraday and finds

that he has educated himself by reading the books he

was supposed to be binding. He gets the job.

1820 - Hans Christian Oersted, during a public lecture,

compass needle to deflect.


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1820 - Andre Marie Ampere, one week afterhearing of Oersted's discovery, shows that

opposite currents attract.

1821 - Humphrey Davy shows that direct currentis carried throughout the volume of a conductorand establishes that

=

is increased as the temperature rises.


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1834 - Faraday discovers self inductance.

1841 - James Prescott Joule shows that energy

is conserved in electrical circuits involving current flow,

thermal heating, and chemical transformations.

notably Faraday, Ampere, Biot, Savard in what has

description of electromagnetism. It is now widely

accepted that light is an electromagnetic wave.


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1881 - Helmholtz, in a lecture in London, points out that

the idea of charged particles in atoms can be consistent

with Maxwell's and Faraday's ideas, helping to pave the

way for our modern picture of particles and fields

disturbance of the aether, as was popular after Maxwell.

And now, Tesla.....................

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A Short History of Electricity