1842 in science

The year 1842 in science and technology involved some significant events, listed below.

Botany

 * Nathaniel Bagshaw Ward publishes On the Growth of Plants in Closely Glazed Cases in London, promoting his concept of the Wardian case.

Exploration

 * Antarctic explorer James Clark Ross charts the eastern side of James Ross Island and on January 23 reaches a Farthest South of 78°09'30"S.

Medicine

 * January – American medical student William E. Clarke of Berkshire Medical College becomes the first person to administer an inhaled anesthetic to facilitate a surgical procedure (dental extraction).
 * March 30 – American physician and pharmacist Crawford Long administers an inhaled anesthetic (diethyl ether) to facilitate a surgical procedure (removal of a neck tumor).
 * English surgeon William Bowman publishes On the Structure and Use of the Malpighian Bodies of the Kidney, identifying Bowman's capsule, a key component of the nephron.
 * Edwin Chadwick's critical Report on an inquiry into the Sanitary Condition of the Labouring Population of Great Britain is published by the Poor Law Commission.

Paleontology

 * Palaeontologist Richard Owen coins the name Dinosauria, hence the Anglicized dinosaur.

Physics

 * Christian Doppler proposes the Doppler effect.
 * Julius Robert von Mayer proposes that work and heat are equivalent. This is independently discovered in 1843 by James Prescott Joule, who names it "mechanical equivalent of heat".

Technology

 * January 8 – Delft University of Technology established by William II of the Netherlands as a 'Royal Academy for the education of civilian engineers'.
 * February 21 – John Greenough is granted the first U.S. patent for the sewing machine.
 * June – James Nasmyth patents his design of steam hammer in England and introduces an improved planing machine.
 * John Herschel discovers the cyanotype (blueprint) photographic process in England.

Events

 * September 14–17 – English naturalist Charles Darwin and his family settle at Down House in Kent.

Awards

 * Copley Medal: James MacCullagh
 * Wollaston Medal: Leopold von Buch

Births

 * February 2 – Julian Sochocki (died 1927), Polish mathematician.
 * February 10 – Agnes Mary Clerke (died 1907) Irish astronomer and author.
 * February 22 – Camille Flammarion (died 1925), French astronomer.
 * March 17 – Rosina Heikel (died 1929), Finnish physician.
 * March 23 – Susan Jane Cunningham (died 1921), American mathematician.
 * April 4 – Édouard Lucas (died 1891, French mathematician.
 * May 7 – Isala Van Diest (died 1916), Belgian physician.
 * May 8 – Emil Christian Hansen (died 1909), Danish fermentation physiologist.
 * June 11 – Carl von Linde (died 1934), German refrigeration engineer.
 * August 23 – Osborne Reynolds (died 1912), Irish-born physicist.
 * September 9 – Elliott Coues (died 1899), American ornithologist.
 * September 20
 * James Dewar (died 1923), Scottish-born chemist.
 * Charles Lapworth (died 1920), English geologist.
 * October 17 – Gustaf Retzius (died 1919), Swedish anatomist.
 * October 24 (O.S. October 12) – Nikolai Menshutkin (died 1907), Russian chemist.
 * November 12 – John William Strutt, 3rd Baron Rayleigh (died 1919), English Nobel Prize-winning physicist.
 * December 3 – Ellen Swallow Richards (d. 1911), American chemist.
 * December 17 – Sophus Lie (died 1899), Norwegian mathematician.

Deaths

 * February 15 – Archibald Menzies (born 1754), Scottish-born botanist.
 * April 28 – Charles Bell (born 1774), Scottish-born anatomist.
 * May 8 – Jules Dumont d'Urville (born 1790), French explorer.
 * June 9 - Maria Dalle Donne (born 1778), Bolognese physician
 * June 30 – Thomas Coke, Earl of Leicester (born 1754), English agriculturalist and geneticist.
 * July 19 – Pierre Joseph Pelletier (born 1788), French chemist.
 * July 25 – Dominique Jean Larrey (born 1766), French military surgeon, pioneer of battlefield medicine.