Events in History
- Apr 22 Madame du Barry becomes King Louis XV's "official" mistress
Historic Invention
Apr 29 Scottish engineer James Watt's patent for a steam engine with a separate condenser enrolled (Patent 913)

James Watt
Birthdays in History
- Apr 3 Christian Günther von Bernstorff, Danish-Prussian statesman and diplomat, born in Copenhagen, Denmark (d. 1835)
- Apr 13 Thomas Lawrence, English portrait painter, born in Bristol, England (d. 1830)
- Apr 25 Marc Isambard Brunel, French-born English engineer (Thames Tunnel), born in Hacqueville, France (d. 1849)