1742 in science

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The year 1742 in science and technology involved some significant events.

Astronomy[]

January 14 – Death of Edmond Halley; James Bradley succeeds him as Astronomer Royal in Great Britain.

June – Christian Goldbach produces Goldbach's conjecture.^[1]
Colin Maclaurin publishes his Treatise on Fluxions in Great Britain, the first systematic exposition of Newton's methods.

Anders Celsius publishes his proposal for a centigrade temperature scale originated in 1741.^[2]

Surgeon Joseph Hurlock publishes his A Practical Treatise upon Dentition, or The breeding of teeth in children in London, the first treatise in English on dentition.

Benjamin Robins publishes his New Principles of Gunnery, containing the determination of the force of gun-powder and an investigation of the difference in the resisting power of the air to swift and slow motions in London, containing a description of his ballistic pendulum and the results of his scientific experiments into improvements in ballistics.^[3]^[4]^[5]
The first large (12 ft focal length) reflecting telescope is made, in Gregorian form, by James Short, for use by Charles Spencer, 3rd Duke of Marlborough, in London.^[6]

March 15 (bapt.) – John Stackhouse, English botanist (died 1819).
May 18 – Lionel Lukin, English inventor (died 1834).
December 3 – James Rennell, English geographer, historian and oceanographer (died 1830).
December 9 – Carl Wilhelm Scheele, Swedish chemist (died 1786).
December 26 – Ignaz von Born, Hungarian metallurgist (died 1791).

^ Crilly, Tony (2007). 50 Mathematical Ideas you really need to know. London: Quercus. p. 37. ISBN 978-1-84724-008-8.
^ Celsius, Anders (1742). "Observationer om twänne beständiga grader på en thermometer" (Observations about two stable degrees on a thermometer). Kungliga Svenska Vetenskapsakademiens Handlingar (Proceedings of the Royal Swedish Academy of Sciences) 3:171-180 and [1].
^ Jervis-Smith, Frederick John (1911). "Chronograph" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 6 (11th ed.). Cambridge University Press. p. 302.
^ Routh, Edward John (1905). The Elementary Part of A Treatise on the Dynamics of a System of Rigid Bodies. London: Macmillan.
^ Ferguson, Niall (2011). Civilization: The West and the Rest. London: Allen Lane. ISBN 978-1-84614-273-4.
^ Museum of the History of Science, Oxford, inventory 98721 (exhibit label noted 2012).
^ "Copley Medal | British scientific award". Encyclopedia Britannica. Retrieved 21 July 2020.