Chronomedia: 1820-1824

1820	Chronomedia index Numbers after entries link to the list of references.	links and notes
•	Manchester Guardian newspaper is founded as a liberal weekly by J E Taylor.	It becomes a daily in 1855
August 4	Saturday Evening Post weekly magazine is launched in the US.	It continues until 1969.
•	Principles of electromagnetic rotation discovered by Michael Faraday (1791-1867).
•	Augustin Fresnel (1788-1827), in his research into the theory of polarised light, discovers that light waves vibrate transversely, at right angles to the direction of propagation, and not longitudinally (like sound).
•	Charles Wheatstone (1802-1875) [right] demonstrates sound reproduction.

1822
July	First Diorama, combining partially translucent paintings with lighting effects, opened in Paris by Louis-Jacques Mandé Daguerre (1759-1851) and Claude-Marie Bouton.
•	J N Nièpce’s first photograph, requiring nine hours’ exposure, is made using a glass plate coated with bitumen of Judea, which hardens when exposed to light.	> 1827
•	The Sunday Times newspaper is founded in London.
	A multifaceted lens for use in lighthouses is invented in France by Augustin Fresnel.

1823
August 2	Weekly New York Mirror and Ladies Literary Gazette, forerunner of the New York Mirror daily newspaper is first published.
September	Second Daguerre/Bouton Diorama opens in Regents Park, London.
•	First British illustrated annual, Forget-me-not, published.
•	Charles Babbage makes his first attempts to construct a calculating machine.

1824
•	Le Globe newspaper founded in Paris.
December	Peter Mark Roget (of Thesaurus fame) presents a paper on the persistence of vision to the Royal Society in London, illustrated with a thaumatrope.
•	Première of Beethoven’s Ninth Symphony ('The Choral') Op.127 in Vienna.