Rittmann was the son of a dentist in
Basel,
Switzerland. He studied music and natural science at the
University of Basel and later he changed to the
University of Geneva. He received his PhD there (1922) for work on
ultramafic rocks of the
Ural Mountains. Rittmann left Geneva to study with
Alfred Lacroix in Paris,
Friedrich Johann Karl Becke in
Vienna,
Ernst Anton Wülfing and
Victor Mordechai Goldschmidt in Heidelberg. In 1926, the rich banker
Immanuel Friedländer founded the Institute for Volcanology in Naples and Rittmann became leading scientist of the institute. His work focused on the
Mount Vesuvius and on the island of
Ischia. This resulted in his first great work: "Evolution und Differentiation des Somma-Vesuvmagmas" (Rittmann, 1933). He drew the right conclusion that
orogenic uplift volcanism (
igneous rocks of the calc series), lacks alkaline
basalts (igneous rocks of the sodic series). At the annual meeting of the German Geological Society in January 1939, he was right opposing the idea that the
Mid-Atlantic Ridge was an orogenic uplift by compression, and his opposition to disregard the
Continental drift theory raised doubts. The work "Über den Zustand des Erdinnern und seine Entstehung aus einem homogenen Urzustand" (Kuhn and Rittmann, 1941) defended the non existence of an iron-nickel
Earth core. His work "Orogénèse et volcanisme" (Rittmann, 1951) with collaboration of W. Kuhn demonstrated that crystalline
mantle is able to creep under its pressure and temperature. His book "Vulkane und ihre Tätigkeit" was translated in five languages (2 ed.) and it was a standard work on volcanism. He received the Gustav-Steinmann-Medaille (1965) and the
doctor honoris causa from the
University of Bern (1959). The Antarctic volcano
Mount Rittmann and the mineral
rittmannite (IMA 1987–048, 08.DH.15) were named in his honour. His daughter Loredana Rittmann is too a volcanologist. ==Quote==