The Physical Society of London, England, was a scientific society which was founded in 1874. In 1921, it was renamed the Physical Society, and in 1960 it merged with the Institute of Physics (IOP), the combined organisation eventually adopting the name of the latter society.
The society was founded due to the efforts of Frederick Guthrie, Professor of Physics at the Royal College of Science, South Kensington, and his assistant, William Fletcher Barrett. They canvassed support for a 'Society for physical research' and on 14 February 1874, the Physical Society of London was formed with an initial membership of 29 people. The Society's first president was John Hall Gladstone.
Meetings were held every two weeks, mainly at Imperial College London. From its beginning, the society held open meetings and demonstrations and published Proceedings of the Physical Society of London. The first Guthrie lecture, now known as the Faraday Medal and Prize, was delivered in 1914. In 1921 the society became the Physical Society, and in 1932 absorbed the Optical Society (of London). The Optical Society published Transactions of the Optical Society from 1899 to 1932.
In 1960, the merger with the Institute of Physics took place, creating the Institute of Physics and the Physical Society, which combined the learned society tradition of the Physical Society with the professional body tradition of the Institute of Physics. Upon being granted a royal charter in 1970, the organisation renamed itself as the Institute of Physics.
In November 2021, a number of members of the civil disobedience group Extinction Rebellion succeeded in infiltrating and briefly disrupting the Lord Mayor’s Show by appearing in the parade using a float disguised under the name of The Physical Society of London.
Lewis, John J. (2003). The Physical Society and Institute of Physics 1874-2002. Institute of Physics Publishing. ISBN 0-7503-0879-6.