Jenő Klupathy

* Košice, 21 October 1861 – † Budapest, 2 March 1931 / physicist, university professor, member of the Hungarian Academy of Sciences (1908) ; ; He completed his secondary school studies at the Košice General Real Gymnasium, where József Sztoczek (1819–1890) was the presiding officer of the graduation examination. This fortunate circumstance also contributed to the fact that between 1876 and 1880 he was able to attend lectures at both the Budapest University of Science and Technology and obtain a teaching certificate. He became Loránd Eötvös's assistant professor, and in 1886 he received his doctorate under him. In the meantime, in 1891 he studied at the Sorbonne in Paris. On his return home, he was appointed as a substitute professor at the university, and then in 1894, when Loránd Eötvös became Minister of Culture, Klupathy replaced him in the department. Meanwhile, he also taught physics at the Barcsay Street High School and held a special electricity course for specialists in the developing postal network, and wrote notes for it. From 1903 he was the first extraordinary teacher of the newly organized practical physics department at the university, and from 1908 he was a regular teacher. In 1910 he was the organizer and director of the practical physics institute. He retired in 1921. ; In 1898 he founded the Budapest University Athletic Club (BEAC), and was its president until 1912. In 1900 he started and edited the journal Uránia until 1912. He achieved results in the field of examining the surface tension of liquids. He had several inventions related to electricity, such as improving the efficiency of the arc lamp used for projection purposes by repositioning the carbon rods. He made the first X-rays in Hungary in 1895, including of the hand of Loránd Eötvös. In his scientific work, he was mainly interested in the practical and technical side of physics. His innovation that he placed one of the carbons of the arc lamps used in projectors horizontally (1895) proved to be successful in practice. In this way, the positive crater radiates its strong light forward, and when the carbon runs out, the position of the light source remains constant relative to the optical axis. His invention related to underwater signals was also presented in New York. ; In the 1900s, he thoroughly studied the operating principle of the Wehnelt electrolytic current interrupter (in the contemporary term: current interrupter) applied to spark inductors that cause spark discharge, and showed that the flowing electric current caused the Peltier phenomenon. The essence of this is that the temperature at the contact point of electrical conductors made of different materials in the circuit increases or decreases depending on the direction of the current. In 1907, while examining the laws of electrons flowing towards the cathode, he established the effect of cathode radiation on the magnetic field. Another significant invention of his was the electrical remote switching using sound, which he patented together with Krisztián Berger in 1908, and for its practical use, the Submarine Wireless Company was established in 1912 in Albany, USA. He was a member of the Hungarian Academy of Sciences from 1908. ; ; His main works: ; Az elektroszág és magnetzég tana, 1891, ; Physikai méresek, 1912.