József Károly Hell

József Károly Hell (1713 to 1789) was a Hungarian mining engineer and inventor who worked in the mining region around Selmecbánya, today Banská Štiavnica in Slovakia. He is credited with inventing the water-pillar engine, a water pumping machine devised in 1749 and first used in 1753. His first machine could pump water up from a depth of 212 meters, and the pumping machines he built between 1749 and 1768 belonged to the best technology in the field worldwide. He also proposed the construction of the tajchy reservoirs around Selmecbánya, which stored water for the mines, and he had been a student of Sámuel Mikoviny from 1737. Both Hungarian and Slovak sources claim him with pride, and the water-pillar principle is still used today, mainly in oil extraction.