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Polishing Amber with fur would cause it to pick up feathers
Greek word for Amber is ‘elektron’
Friction separates charges
http://www.mathopenref.com/thales.html
http://www-history.mcs.st-andrews.ac.uk/~history/Mathematicians/Thales.html
http://en.wikipedia.org/wiki/Thales
Born Boston, Mass.
Printer, Scientist, Inventor, Civic activist, diplomat & candle maker – also found time to be one of the founding fathers of USA.
Fluent in five languages, invented catheter, swimfins, glass harmonica & bifocal lenses.
Proposed that “Resinous” & “Vitreous” electrical fluid are the same under different pressures, labelled as positive and negative.
1750 Proposed experiment to prove lightning is electricity
1752 Flew kite in ‘storm like’ cloud & gathered charge.
Prof. Richmann (St. Petersburg) RIP
Invented lightning rod.
http://www.fi.edu/franklin/
http://www2.fi.edu/exhibits/permanent/electricity.php
en.wikipedia.org/wiki/Benjamin_Franklin
Lived in Bologna, Italy
Dispute as to first observation
  -- Experiments in static electricity
  -- Steel scalpel & copper stand
  -- Wife cooking frog soup
http://www.corrosion-doctors.org/Biographies/GalvaniBio.htm
http://www.geocities.com/bioelectrochemistry/galvani.htm
http://en.wikipedia.org/wiki/Galvani
Born in Lombardy, Italy
Studied chemistry
Discovered methane & experimented igniting gases with static electricity
1800 Developed battery
Initially wine goblets in series
then stack of zinc/silver/cardboard
Noted that electric tension increased as number of stages
Used tongue to test !!
Didn’t appreciate role of electrolyte in system
Different to static electricity – all conductors vs all insulators
Zinc Anode corrodes releasing zinc ions into solution, liberates electrons
Hydrogen ions from solution combine with electrons at cathode to form Hydrogen gas
Imbalance of electrons will flow through external circuit.
Can make similar cell with zinc/copper/lemon or potato
http://www.madsci.org/experiments/archive/889917606.Ch.html
http://inventors.about.com/library/inventors/blbattery.htm
Volta didn’t quite understand
1820- A key year in the history of electricity & communications
HC Oersted noticed an electric current deflected a compass needle.
Johann Schweigger invented galvanometer
 Wire coiled around compass è increased sensitive
http://en.wikipedia.org/wiki/Hans_Christian_%C3%98rsted
http://scienceworld.wolfram.com/biography/Oersted.html
http://chem.ch.huji.ac.il/~eugeniik/history/schweigger.html
b. near Lyon, France 1775
Child Prodigy – maths with pebbles
Learned Latin to study Euler & Bernoulli
Prof of physics & chemistry at Bourg in 1801 (age 26)
Prof of Maths in Lyon 1804
Prof of Maths in Paris 1809
1820 Oersted’s discovery – presented paper formalising EM theory to acadame Francais 1 week later.
http://www.corrosion-doctors.org/Biographies/AmperBio.htm
http://en.wikipedia.org/wiki/Andr%C3%A9-Marie_Amp%C3%A8re
1832 Baron Schilling von Canstedt (Russia), System had 6 galvanometers connected by 8 wires to transmitting station – across apartment.
1833 Carl Friedrich Gauss & Wilhelm Weber 1km
single pair of wires, 4 amplitudes & direction of current – developed code
Charles Wheatstone  & William Cooke
Both had been working on systems based on Schilling’s, joined forces in 1837.   5 needle system (25 letters) Euston Stn – Camden (2.4km) NWR not impressed despite good demo. 6 wires = 5 signals + return
Needles point to letter being transmitted
1839. System installed for GWR from Paddington to West Drayton (21km) extended to Slough in 1841
Arrest of John Tawell for murder of Sarah Hart. Boarded train at Slough for London. Police sent “He is the garb of a kwaker with a brown coat on which reaches nearly to his feet.”
Tried & executed è good publicity for telegraphy !!
http://www.connected-earth.com/Galleries/Telecommunicationsage/Thetelegraph/index.htm
http://chem.ch.huji.ac.il/~eugeniik/history/wheatstone.html
http://www.kcl.ac.uk/depsta/iss/library/speccoll/host/wheatstone.html
Sturgeon
Born Lancashire, 1783
Army 1802
1824 Lecturer at military college, Addiscombe Surrey
Scottish American
Greatest American scientist since Franklin
Unit of inductance named after him.
Schoolmaster in Albany, NY
First to coil insulated wire tightly to make strong electromagnet
Used wife’s petticoats to insulated wire
1828 – 9lbs
1830 – 750lbs
1831 - 1500lbs
1837 Invents relay by using electromagnet to operate switch
Form of amplification, enables long distance telegraphy
Electric Universe: David Bodanis Abacus (19 Jan 2006)
ISBN: 0349117667
http://www.davidbodanis.com/pages/books_pg.html
http://etcweb.princeton.edu/CampusWWW/Companion/henry_joseph.html
http://experts.about.com/e/j/jo/Joseph_Henry.htm
Samuel Morse (20) lived off parents money studied fine arts in Yale.
“My ambition is to be among those who shall revive the splendour of the fifteenth century; to rival the genius of a Raphael, a Michelangelo, or a Titian”
Calvinist, believed secret conspiracies of Catholics & Jesuits were destroying America. Ran for mayor of New York in 1836 “We have to resist this monstrous evil that threatens us”
Develop telegraph as way of fighting back…
Visited Henry in Princetown & got most of his ideas – patented them
Formed partnership with Vail
1838 – first system
1844 line opened, message sent from Washington to Baltimore
“What hath God wrought” – from Numbers 23:23
Farmers destroyed lines in Kentucky 1849 – remove electricity from air & stop rain.
http://home.clara.net/rod.beavon/samuel.htm
http://en.wikipedia.org/wiki/Samuel_Morse
http://www.juliantrubin.com/bigten/morsetelegraph.html
http://www.hrw.com/si/social/si_1914/si_informationage/si_img/TELGRH.GIF
http://memory.loc.gov/mss/mcc/019/0001.gif