|Died||9 October 1857 (aged 64)|
|Known for||marine propeller|
Joseph Ludwig Franz Ressel (Czech: Josef Ludvík František Ressel; 29 June 1793 – 9 October 1857) was an Austrian forester and inventor of Czech-German descent, who designed one of the first working ship's propellers.
Ressel was born in Chrudim, Bohemia then part of the Holy Roman Empire ruled by the Habsburg Monarchy, which became part of the Austrian Empire at his death (now the Czech Republic). His father Anton Hermann Ressel was a native German speaker, and his mother Marie Anna Konvičková was a native Czech speaker. He studied in the Linz Gymnasium, Budweis (in today's České Budějovice) artillery school, University of Vienna and the Mariabrunn Forestry Academy at Mariabrunn Monastery then near (now in) Vienna.
He worked for the Austrian government as a forester in the more southern parts of the monarchy, including in Motovun, Istria (modern-day Croatia). His work was to secure a supply of quality wood for the Navy. He worked in Landstrass (Kostanjevica on the Krka river in Carniola in modern-day Slovenia), where he tested his ship propellers for the first time. In 1821 he was transferred to Trieste (modern-day Italy), the biggest port of the Austrian Empire, where his tests were successful. He was awarded a propeller patent in 1827. He modified a steam-powered boat Civetta by 1829 and test-drove it in the Trieste harbor at six knots before the steam conduits exploded. Because of this misfortune, the police banned further testing. The explosion was not caused by the tested propeller as many believed at the time.
As early as 1804, the American John Fitch is credited with a screw propeller, which was unsuccessful. In 1836, the Englishman Francis Pettit Smith tested a screw propeller similar to Ressel's. The first transatlantic journey of a ship powered by a screw-propeller was by the SS Great Britain in 1845. Propeller design stabilized in the 1880s.
Besides having been called "the inventor of the propeller", he was also called the inventor of the steamship and a monument to him in a park in Vienna commemorates him as “the one and only inventor of the screw propeller and steam shipping”. He was also commemorated on Austria's 500 Schilling banknote in the mid 1960s (P139), which shows him on the front and the ship "Civetta" on the back.
Among other Ressel's inventions are pneumatic post and ball and cylinder bearings. He was granted numerous patents during his life.
- Josef Ressel Relevant Non-Istrians, istria.net, accessed 2012-07-30
- Erhard Marschner: "Josef Ressel. Erfinder der Schiffsschraube - Seine Vorfahren und Nachkommen" [Josef Ressel. One of the designers of a ship's propeller - its ancestors and descendants], 1979, ISBN 3-7686-6016-8.
- Václav Gutwirth: "Vynálezce Josef Ressel" [Inventor Josef Ressel], 1943, Prague.
- Jiří Charvát, Pavel Kobetič et al.: "Josef Ressel a Chrudim" [Josef Ressel and Chrudim], 1986, published by the Chrudim Regional Museum. The museum keeps collection of porpotions about Ressel.