Franz Serafin Exner (24 March 1849 – 15 October 1926) was an Austrian physicist. Life Exner came from one of the most important university families of the Austrian-Hungarian empire. The same Exner family included , , Sigmund Exner, and . Exner was youngest of the five children who survived to adulthood of parents Franz Serafin Exner (1802-1853) and Charlotte Dusensy (1816–1859). His father Franz Serafin was, from 1831 to 1848, a professor of philosophy in Prague and from 1848 onwards a member of the Board of Education in Vienna, becoming an influential reformer of Austrian university education. Franz Exner began his university Physics studies at Vienna in 1867. He received a doctorate from the University of Vienna in 1871, after an academic year at Zürich under August Kundt, also working alongside Wilhelm Conrad Röntgen, Kundt's student and, especially through the 1879s, regular research assistant/partner. The greatest influence on Exner's student career was probably the theoretical physicist Viktor von Lang, who had taken the University Chair in Physics at a still relatively young age in 1866, and who played a key role in encouraging and backing his gifted student. Exner received his habilitation in 1874 with a work entitled "On the Diffusion through Liquid Lamellas" ("Über die Diffusion durch Flüssigkeitslamellen"). He continued to work for von Lang as the latter's research assistant till 1879. Between 1874 and 1879 he also held a lectureship at the University of Natural Resources and Life Sciences, Vienna "k.k. Hochschule für Bodencultur" (loosely, "Imperial College for Earth Sciences") which provided both a welcome supplementary income and the chance to share his ideas and insights with the large audiences attracted by his lectures. In 1879, still only 30, Franz Exner accepted an Extraordinary Professorship at the university. In 1885 he was elected to corresponding membership of the Austrian Academy of Sciences and Humanities. Full membership would follow in 1896. Promotion came in 1891 when he was offered and accepted an "ordinary" (full) professorship at the university Chemical physics Institute in the Türkenstraße. He arrived in the post with a clear agenda for change, which he now implemented. He created a new "school for experimental physics" to which, through an rare combination of sound judgment and good fortune, he was able to entice a stellar generation of younger researchers. New laboratory courses were inaugurated for advanced student, notably in respect of Physics and Medicine. Exner'sappointment to the professorship