The name of the Physical Society of London (founded in 1874) was changed in 1932 to Physical Society. In 1933 this body absorbed the Optical Society created in 1899. In 1960 the Physical Society merged with the Institute of Physics to form the Institute of Physics and the Physical Society. In 1971 the name changed to the Institute of Physics. Works by these bodies are entered under the name used at the time of publication.