1965 deaths

Ernst Erich Jacobsthal (16 October 1882, Berlin – 6 February 1965, Überlingen) was a German mathematician, and brother to the archaeologist Paul Jacobsthal.
In 1906, he earned his PhD at the University of Berlin, where he was a student of Georg Frobenius, Hermann Schwarz and Issai Schur; his dissertation, Anwendung einer Formel aus der Theorie der quadratischen Reste (Application of a Formula from the Theory of Quadratic Residues), provided a proof that prime numbers of the form 4n + 1 are the sum of two square numbers. In 1934, he was fired from his professorship at the Technische Hochschule Berlin, because of his Jewish origins. In 1939 he fled to Norway and became after the war a professor at the Norwegian Institute of Technology in Trondheim.

Hans Meerwein (May 20, 1879 in Hamburg, Germany – October 24, 1965 in Marburg, Germany) was a German chemist.
Several reactions and reagents bear his name, most notably the Meerwein–Ponndorf–Verley reduction, the Wagner–Meerwein rearrangement, the Meerwein arylation reaction, and Meerwein's salt.

Ludwig Hirschfeld Mack (11 July 1893, in Frankfurt-am-Main – 7 January 1965, in Allambie Heights, in Sydney) was a German-born Australian artist.
His formative education was 1912–1914 at Debschitz art school in Munich. He studied at the Bauhaus from 1919–24 and remained working there until 1926 where, along with Kurt Schwerdtfeger, he further developed the Farblichtspiele ('coloured-light-plays'), which used a projection device to produced moving colours on a transparent screen accompanied by music composed by Hirschfeld Mack. It is now regarded as an early form of multimedia. He was a participant, along with the former Bauhaus master Gertrud Grunow, in den II. Kongreß für Farbe-Ton-Forschung (Hamburg 1. - 5. Oktober 1930) (English: Second Congress for Colour-Sound Research, Hamburg). In 1923 he participated in the prestigious film festival "Der Absolute Film in Berlin with other film producers such as Hans Richter Viking Eggeling, Walter Ruttmann, Fernand Léger. Francis Picabia and Renée Clair. Music and colour theory remained lifelong interests, informing his art work in a number of media, and it was the inspiration for his well-respected and influential teaching.

Franz Doelle (9 November 1883 – 15 March 1965) was a German composer. He worked on around fifty film scores during his career many of them operetta films.

Werner Pledath (26 April 1898 – 6 December 1965) was a German actor who appeared in many films during a lengthy career. He generally played supporting roles such as in Five from the Jazz Band (1932). Pledath specialized in playing powerful, authority figures. Following the Second World War he appeared in several films made in East Germany.

Melchor Ferrer Dalmau (1888–1965) was a Spanish historian and a Carlist militant. He is known mostly as principal author of a massive, 30-volume series titled Historia del tradicionalismo español, considered fundamental work of reference for any student of Carlism. Ferrer is recognized also as "periodista" (journalist), chief editor of a national and a few local traditionalist dailies and contributor to a number of others. Politically he maintained a low profile, though periodically he was member of the party executive, and during internal party strife of the early 1960s his support might have tipped the balance in favor of the progressist faction.

Gabriel Steiner (26 May 1883, Ulm – 10 August 1965, Detroit) was a German-American neurologist known for his research of multiple sclerosis. In his studies, he postulated a link between multiple sclerosis and certain forms of spirochetes.Of Jewish ancestry, he studied medicine at the universities of Munich, Würzburg, Freiburg and Strasbourg, receiving his doctorate at the latter university in 1910. In 1913 he qualified as a lecturer in neurology and psychiatry, and from 1920, worked as an associate professor at the University of Heidelberg. Here, he was also head of the laboratory for pathological anatomy at the psychiatric-neurological clinic.In 1936 he emigrated to the United States, where from 1937 to 1954, he served as a professor of neurology and neuropathology at Wayne State University School of Medicine in Detroit. In retirement, he was director of the Michigan Multiple Sclerosis Center.

Georges Rousseau-Decelle (2 January 1878, in Roche-sur-Yon – 1965) was a French entomologist.
Rousseau-Decelle amassed a large collection of worldwide butterflies containing many rare species, notably in the genera Morpho and Ornithoptera. He was primarily interested in infraspecific variation.
Georges Rousseau-Decelle was a chevalier de la Légion d’Honneur and a member of the Société entomologique de France.

Lucien Sophie Albert Marie von Römer (23 August 1873 – 23 December 1965) was a Dutch physician, botanist and writer. He often wrote about homosexuality, and argued that it was an innate characteristic. He practiced medicine in the Dutch East Indies (later Indonesia) in his later life. His views parallel those of psychiatrist Sigmund Freud on this topic.

Eligio Perucca (28 March 1890 in Potenza – 5 January 1965 in Rome) was an Italian physics instructor and researcher at the University of Turin in Italy in the early decades of the twentieth century. He later served a professorship at the nearby Polytechnic University of Turin. He discovered an important principle in stereochemistry in 1919, but his contribution was overlooked and forgotten until recently.