RESSEL, Josef

R. was the son of a tax official from the town of Chrudim (Moravia). He attended the gymnasium in Linz, where he graduated with honours. He enrolled at the Artillery School, which he had to leave after three years due to health problems.
Between 1812 and 1814 he studied technology and natural science at the University of Vienna. His whole life was characterised by his interest in technology. Unfortunately he had to interrupt his studies due to financial issues but was awarded a scholarship which allowed him to finish a two-year forestry academy in Mariabrunn.
On 16th March 1817 he entered the service of the district forest engineer in Pleterje, and between 1810-48 he also worked in Ljubljana, Trieste, Motovun (Croatia) and Venice.
As a forest engineer, R. supplied timber to the shipyards in the northern Adriatic and contributed to the introduction of modern forestry management within his area of service. In Slovenia he can be credited particularly with his reforestation work. In addition, he was also involved in soil improvement and planned extensive drainage works in the vicinity of Venice and in the Neretva Valley.
In addition, R. was committed to technical inventions, in particular the development of the Archimedes' screw into a ship propeller. He started to work on this idea during his stay in Vienna. He made the first experimental screw propeller in February 1827, for which he was awarded a patent that same year. In the autumn of 1829 he tested the screw propeller on the steam-powered boat Chivetta in the Bay of Trieste, but after only a few hundred metres, the steam pipes exploded.
Nevertheless, the screw propeller fundamentally proved itself in the experiment and R. designed improvements, in particular with regard to the design of the steam engines. His idea was to install the propeller longitudinally towards the ship’s stern to allow the vessel to be steered without a rudder.