|
1550
|
Girolamo
Cardano distinguishes between magnetism and the amber effect. |
| 1600 |
William
Gilbert published De Magnette, offering an effluvium theory
of electricity; debunks "occult quality" and "fatty humor"
theories. |
| 1629 |
Niccolo
Cabeo (Philososphia Magnetica) observes repulsion without
understanding it; promotes air-displacement theory. |
| 1672 |
Otto
von Guericke transmits electricity several feet though a
piece of thread. |
| 1705 |
Francis
Hauksbee discovers "electrification by influence" (i.e.
across a space). |
| 1720s |
Stephen
Gray transmits an electrical effect up to 650 feet through
packthread; discovers the principle of conductor and insulator. |
| 1733 |
Charles
Dufay postulates two kinds of electricity (called vitreous
and resinous electricities). |
| 1745 |
E.G.
von Kleist builds a condenser by driving a nail through
the seal of a water bottle. |
| 1746 |
Pieter
van Musschenbroek invents the "Leyden jar". Benjamin Franklin
begins experiments that produce his plus/minus (one-fluid)
theory of electricity. |
| 1780 |
Allessandro
Volta invents the "voltaic pile" (a crude battery). |
| 1785 |
Auguste
Coulomb shows that electricity (like gravity) follows the
inverse square law of attraction. |
| 1819-27 |
Oersted,
Ampere, Biot, Savart & Ohn describe the relationships between
magnetism, voltage, current, and electrical resistance. |
| 1822 |
Charles
Babbage builds a mechanical predecessor of the computer. |
| 1831 |
Michael
Faraday invents a crude generator (converting mechanical
energy to electrical energy). |
| 1832 |
Gauss
develops a measure for magnetism; in 1840 Weber does so
for electricity. |
| 1861 |
Johann
Reis builds a machine to transmit a voice signal (called
a "telephone"); A.G. Bell in 1876 receives a U.S. patent
for a different and much better telephone design |
| 1873 |
J.C.
Maxwell develops mathematical laws governing all of electromagnetism.
|
| 1879 |
Thomas
Edison invents a commercially viable carbon-filament incandescent
bulb. |
| 1888 |
Nicholas
Tesla invents alternating current and the induction motor. |
| 1897 |
J.J.
Thomson proposes that electricity is composed not of waves
but of particles, which we now call "electrons". |
| 1942-5 |
ENIAC,
the first electronic computer, is built. |
| 1948 |
The
transistor is developed at Bell Laboratories. |
| 1970s |
The
microprocessor and other integrated circuits become the
basis of personal computers. |
