**Lóránd Eötvös** was a Hungarian mathematician and physicists who published works on surface tension and gravitation.

- Had he only published in Hungarian, Eötvös would have achieved far less in the way of an international reputation so he published his most important results in German as well as Hungarian.
- To international scientists, therefore, he is known by the name which appeared on these German papers, namely Roland, Baron Eötvös.
- His full title is, however, far more grand: in Hungarian Vásárosnaményi Báro Eötvös Lóránd; in English Roland, Baron Eötvös of Vásárosnaményi.
- Lóránd rapidly showed talents in a whole range of artistic pursuits, and he became highly skilled at drawing, and wrote poetry.
- At school Eötvös studied Hungarian, German, mathematics, history, geography, biology, mineralogy, and physics.
- Eötvös was always more interested in mathematics and science than in law and while he studied law in courses at the university, he took private lessons in mathematics from Otto Petzval.
- Helmholtz liked to spend as much time as possible with his students and showed Eötvös the value of individual discussions.
- Eötvös published on surface tension between 1876 and 1886, a topic he had become interested in while studying with Franz Neumann in Königsberg.
- At this time Eötvös had devised an instrument to measure the constant of surface tension.
- Presenting his ideas in Franz Neumann's seminar had led to him receiving praise from his professor, and Eötvös began to consider problems in the topic.
- He discovered Eötvös's law of surface tension which states that the temperature coefficient of the molecular surface energy of a liquid is independent of the nature of simple unassociated liquids.
- He invented the Eötvös balance and showed that, to a high degree of accuracy, gravitational mass and inertial mass are equivalent.
- By developing the complete theory of the Eötvös balance, he was able to push its sensitivity to such a point that it took decades to devise methods for exceeding his precision.
- Eötvös, and his team of researchers, did indeed check this old claim of Galileo with very much higher accuracy than had previously been achieved.
- From June 1894 to January 1895 Eötvös was the minister of public instruction in the Cabinet of Sandor Wekerle.
- One of the main achievements of his short period of office was the founding of the Eötvös Collegium to improve the teaching of Hungarian secondary school teachers.
- Eötvös founded the Hungarian Society for Mathematics in 1885 and after physicists also wished to be part of the Society, he founded the Mathematical and Physical Society in 1891.
- After Eötvös died in 1919, the Society was renamed the Eötvös Lóránd Mathematical and Physical Society.
- What was once the Péter Pázmány University in Budapest is now known as the Lóránd Eötvös University.
- In 1873 Eötvös became a corresponding member of the Hungarian Academy of Sciences, being elected as a full member in 1883.
- Although this was a three year term, Eötvös continued to be re-elected to the position for sixteen years until he resigned in 1905.
- Eötvös had several hobbies.
- This was not simply a little recreation, for Eötvös soon gained the reputation as one of Europe's most famous mountaineers.
- Climbing also fitted in with another of Eötvös's hobbies, namely photography.
- Since on such occasions he would take the photographs, they tend to show other members of Eötvös's party but not Eötvös himself.

Born 27 July 1848, Pest (now part of Budapest), Hungary. Died 8 April 1919, Budapest, Hungary.

View full biography at MacTutor

Origin Hungary

**O’Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive