Ressel, Josef

Born June 29, 1793, in Chrudim, Bohemia; died Oct. 10, 1857, in Ljubljana. Czech inventor.

Ressel studied at the University of Vienna and at the Vienna Forestry Academy and graduated from the latter institution in 1817. He worked as a forester near Trieste. In 1812, Ressel worked out a design for a ship whose propulsion was based on the use of Archimedes’ screw. He successfully tested a screw propeller on a boat in 1826 and obtained the Austrian patent for this propeller in 1827. In 1829 he built the screw-steamer Civetta, which had a displacement of 33 tons. Ressel’s new propeller permitted the vessel to attain a speed of approximately 6 knots. Further work was halted because of damage to the ship’s steam engine and lack of funds.