Editing 1808 in science (section)

==Mathematics==
* French mathematician [[Christian Kramp]] introduces the notation ''n''<nowiki>!</nowiki> in [[factorial]]s.<ref>''Elements d'arithmétique universelle.'' {{citation|title=Number Story: From Counting to Cryptography|last=Higgins|first=Peter|year=2008|publisher=Copernicus|location=New York|isbn=978-1-84800-000-1|page=12}}</ref>
* German mathematician [[Carl Friedrich Gauss]] publishes ''Theorematis arithmetici demonstratio nova'', introducing [[Gauss's lemma (number theory)|Gauss's lemma]] in the third proof of [[quadratic reciprocity]].
* [[Irish American]] mathematician [[Robert Adrain]] produces a formulation of the method of [[least squares]].<ref>Published in his own journal, ''The Analyst, or, Mathematical Museum'' '''1'''(4), probably issued in 1809. {{cite ODNB|first=Stephen M.|last=Stigler|title=Adrain, Robert (1775–1843)|year=2004|url=http://www.oxforddnb.com/view/article/172|accessdate=2012-01-23|doi=10.1093/ref:odnb/172}}</ref>