Science and technology, 1918–1939

At the start of the 20th century science turned directly into a productive force, which led to the scientific and technological revolution. In physics the atomic nucleus was studied: in 1938 German scientists discovered the fission of the uranium nucleus, in 1942 Enrico Fermi started the first atomic reactor in Chicago, and the first nuclear test took place in the USA in 1945. In medicine, Banting and his colleagues isolated insulin in 1921–1922 and began using it in treatment, and in 1928 Alexander Fleming discovered penicillin; this opened the age of antibiotics and changed the treatment of infectious diseases. In communications, sound film (The Jazz Singer, 1927), radio broadcasting (the BBC as a public corporation from 1927) and electronic television developed, while chemistry produced synthetic fibres such as nylon. By the 1930s a large part of industry was electrified, and personal cars, telephones and refrigerators entered daily life.