German pharmacologist and physiologist who discovered the diuretic effect of the excretions of the pituitary gland. His best known book Körperstellung (“Posture”), a study of functional neurology, was published in Berlin in 1924, and translated into English in 1987. In this book Magnus describes the reflexes involved in mammal posture. The Magnus & De Kleijn reflexes are named after Magnus and his colleague Adriaan de Kleijn (1883–1949). The head and neck reflexes of mammals cause the body to follow automatically when the head moves. He also researched the reflexes of the intestines and phenomena such as motion sickness.
The pharmacological research of Rudolf Magnus was focussed on the effect of medication on the heart, blood vessels, lungs and the gastrointestinal tract. Thus he studied the effects of narcotics, as well as poison gasses on the lungs. He conducted a poison gas study during World War I when he served as an army doctor in Germany.
Magnus had five children, Karl (1903-1989), a lung specialist; Margarete (Gretl, 1905-1968) who worked as his secretary and translator; Dorothea who died aged 11; Erica (1909-1991), an architect; and Otto (1913-2014), a neurologist who wrote Rudolf Magnus, Physiologist and Pharmacologist: A Biography (Royal Netherlands Academy of Arts and Sciences, 2002).
Rudolf Magnus died on 25 July 1927 in Pontresina, Switzerland at age 53. Had he lived another year, he likely would have been awarded the Nobel Prize for his work on animal reflexes. The authors of Nobel, the Man and his Prizes by H. Schück et al., edited by the Nobel Foundation (2nd ed. Amsterdam, 1962, p. 311) wrote of Magnus and his co-worker De Kleyn: “The examiner [1927] declared that the work done by Magnus and De Kleyn clearly deserved a prize, and the prospects for an award seemed most favourable when Magnus unexpectedly died.”

Link to Wikipedia biography