The year 1843 in science and technology involved
some significant events, listed below.
== Astronomy ==
March 11–14 – Eta Carinae flares to become
the second brightest star.
February 5–April 19 – "Great March Comet"
observed.
Heinrich Schwabe reports a periodic change
in the number of sunspots: they wax and wane
in number according to a ten-year cycle.
== Chemistry ==
Jean-Baptiste Dumas names lactose.
Carl Mosander discovers Terbium and Erbium.
John J. Waterston produces an account of the
kinetic theory of gases.
== Mathematics ==
September – Ada Lovelace translates and
expands Menabrea’s notes on Charles Babbage's
analytical engine, including an algorithm
for calculating a sequence of Bernoulli numbers,
regarded as the world's first computer program.
October 16 – William Rowan Hamilton discovers
the calculus of quaternions and deduces that
they are non-commutative.
Arthur Cayley and James Joseph Sylvester found
the algebraic invariant theory.
John T. Graves discovers the octonions.
Pierre-Alphonse Laurent discovers and presents
the Laurent expansion theorem.
== Physics ==
James Prescott Joule experimentally finds
the mechanical equivalent of heat.
Ohm's acoustic law was proposed by German
physicist Georg Ohm.
== Physiology and medicine ==
British surgeon James Braid publishes Neurypnology:
or the Rationale of Nervous Sleep, a key text
in the history of hypnotism.
Oliver Wendell Holmes, Sr., argues that puerperal
fever is spread by lack of hygiene in physicians.
== Technology ==
March 25 – Completion of the Thames Tunnel,
the first bored underwater tunnel in the world
(engineer: Marc Isambard Brunel).
July 19 – Launch of SS Great Britain, the
first iron-hulled, propeller-driven ship to
cross the Atlantic Ocean (designer: Isambard
Kingdom Brunel).
November 21 – Thomas Hancock patents the
vulcanisation of rubber using sulphur in the
United Kingdom
The steam powered rotary printing press is
invented by Richard March Hoe in the United
States.
Robert Stirling and his brother James convert
a steam engine at a Dundee factory to operate
as a Stirling engine.
The first public telegraph line in the United
Kingdom is laid between Paddington and Slough.
== Publications ==
October – Anna Atkins begins publication
of Photographs of British Algae: Cyanotype
Impressions, a collection of contact printed
cyanotype photograms of algae which forms
the first book illustrated with photographic
images.
== Awards ==
Copley Medal: Jean-Baptiste Dumas
Wollaston Medal for Geology: Jean-Baptiste
Elie de Beaumont; Pierre Armand Dufrenoy
== Births ==
January 13 – David Ferrier (died 1928),
Scottish neurologist.
May 6 – G. K. Gilbert (died 1918), American
geologist.
June 12 – David Gill (died 1914), Scottish
astronomer.
June 23 – Paul Heinrich von Groth (died
1927), German mineralogist.
July 24 – William de Wiveleslie Abney (died
1920), English astronomer.
August 17 – Alexandre Lacassagne (died 1924),
French forensic scientist.
November 30 – Martha Ripley (died 1912),
American physician.
December 11 – Robert Koch (died 1910), German
physician, famous for the discovery of the
tubercle bacillus (1882) and the cholera bacillus
(1883) and for his development of Koch's postulates;
awarded the Nobel Prize in Physiology or Medicine
in 1905
Adelaida Lukanina (died 1908), Russian chemist.
== Deaths ==
July 25 – Charles Macintosh (born 1766),
Scottish inventor of a waterproof fabric.
August 10 – Robert Adrain (born 1775), Irish
American mathematician.
September 11 – Joseph Nicollet (born 1786),
French geographer, explorer, mathematician
and astronomer.
September 19 – Gaspard-Gustave Coriolis
(born 1792), French mathematician and discoverer
of the Coriolis effect.
September 30 – Richard Harlan (born 1796),
American zoologist.
November 16 – Abraham Colles (born 1773),
Anglo-Irish surgeon
