Before the beginning of the First World War, Oxford was not a university whose name immediately sprang to mind when the subject 'physics' was mentioned. Oxford did not have an association with any of the great British physicists of the nineteenth century such as Young, Faraday, Kelvin, Rayleigh and Maxwell, and had not gained a reputation such as that enjoyed in the University by astronomy, mathematics and chemistry. Only in the second half of the seventeenth century had there been in Oxford those whose names are remembered to the present day in the world of physics: Boyle and Hooke. The former, with the then-professor of astronomy, Wren, attended meetings in Wadham College of the Philosophical Society of Oxford. They, with a like-minded group which met in the Bull-Head Tavern in London, founded the Royal Society in 1660. In 1663 Hooke became ‘curator of experiments’ and later secretary of the Society.

At the beginning of the eighteenth century the University appointed a Reader in Experimental Philosophy, the name by which physics was then known in Oxford (incidentally, the subject of one of the present physics professorships is still described in this way), but the post was part-time, and the duties of the Reader were carried out by the professor of astronomy. It was not until 1839 that the post became full-time with the appointment of the Reverend Robert Walker.

Experimental Philosophy was first examined as a degree subject in 1850. The Reader was promoted to Professor in 1860, but neither he nor his successor, Robert Clifton, who held office until 1915, had any interest in research. With his available funds, Clifton purchased a wide range of instruments for teaching; he was responsible for improvements in some of them, which were taken up commercially by laboratory suppliers.

The Clarendon Laboratory

The original Clarendon Laboratory, the first purpose-built physics laboratory in the country, was completed in 1872 as a result of an offer of £10,000 from the trustees of the estate of the first Earl of Clarendon; the building, much enlarged, was incorporated in the Department of Earth Sciences and is now mainly occupied by the Department of Computer Science. It gave adequate space for teaching, which had previously taken place wherever makeshift accommodation could be found. After Clifton's retirement in 1915, considerable refurbishment of the laboratory was required: it had no mains electricity and the only lighting was from fishtail gas burners; an 1894 photograph of the workshop (11 KB) shows, as the main items of equipment, a treadle operated lathe and a blacksmith's anvil. But the overall picture had been improved by the creation in 1900 of a new physics chair, to which was appointed Townsend, a researcher in the field of gaseous ions and electrical discharge physics, charged with the teaching of electricity and magnetism.

A new laboratory, the Electrical Laboratory (now the Townsend Building of the Clarendon Laboratory) was built in 1910 and occupied by him and his research team. Here Moseley carried out his experiments which established the ordering of the elements in terms of their atomic numbers, which would almost certainly have gained him a Nobel Prize had he not met his tragic death as an army officer in 1915. Townsend retired in 1941; at no stage had there been significant collaboration with the Clarendon Laboratory except in the sharing of undergraduate teaching.

A turning point

The turning point in physics at Oxford came in 1919 with the appointment of Lindemann (later Lord Cherwell) as Clifton's successor as head of the Clarendon Laboratory. He had a considerable reputation as a brilliant physicist before the First World War, and for his application of the scientific method to the war effort. Although he did little research of his own between 1919 and his resignation in 1956, he built up a physics department which was to rival any in the country; initially the main development was in the low-temperature field, with significant contributions in optical spectroscopy and atmospheric physics.

Coupled with this was a great expansion of space and facilities for teaching and research which has continued to the present day. In 1939 the old Clarendon Laboratory was vacated and a move was made to a new and far larger modern building, now the Lindemann Building of the Clarendon Laboratory. Throughout the Second World War, academic research was suspended and the laboratory was engaged in two aspects of the war effort: the separation of uranium isotopes and the development of microwave devices for radar. Work in the latter field provided a source of microwave radiation, and a knowledge of the techniques for utilising it, which opened up the field of microwave spectroscopy which continues at the present day. This, and the broad field of condensed matter physics, is supported by the low-temperature and high magnetic field facilities which are among the finest in the country. The Clarendon Laboratory became associated with lasers from the early days of the subject, and has made significant contributions both to the development of lasers and to their application to a wide range of research fields.

Six specialist sub-departments

Physics is now divided into six separate sub-departments, of which the Clarendon Laboratory houses two: Atomic and Laser Physics, and Condensed Matter Physics. Particle Physics, which was a minor research subject (then Nuclear Physics) in the inter-war years, expanded greatly subsequently, and now is concerned mainly with elementary particle physics, using the facilities at CERN and other centres. Atmospheric, Oceanic and Planetary Physics, which in Oxford originated with work on the upper atmosphere and the ozone layer in the 1920s, now includes satellite instrumentation among its activities. All these sub-departments, which are concerned with experimental work, are supported by first-class workshop facilities. Townsend's professorship was converted to a chair of Theoretical Physics at the end of the war, and today’s Rudolf Peierls Centre for Theoretical Physics provides invaluable collaboration with the other departments. Astronomy, formerly a distinct department, has become the sixth of the physics sub-departments: Astrophysics.

The Department of Physics has expanded to such a size that a growth in accommodation was inevitable. The Clarendon Laboratory now consists of the Lindemann, Townsend and Simon buildings; Particle Physics, Astrophysics and the bulk of the teaching laboratories are housed in a separate laboratory approximately equal in size to the Clarendon, the Denys Wilkinson building; Atmospheric, Oceanic and Planetary Physics has its own separate building, the Robert Hooke and the Rudolf Peierls Centre for Theoretical Physics took up residency in the state of the art, award-winning Beecroft building in 2018. A similar expansion has taken place in the student numbers: before the Second World War there were about 90 physics undergraduates and less than ten graduate students, working for doctorates, at any one time. Today, we welcome an annual cohort of around 700 undergraduates and some 450 postgraduates.

We maintain an archive room with many old scientific instruments ranging from Helmholz resonators to a Kelvin current balance and any enquiries can be made via contact@physics.ox.ac.uk

Clarendon Laboratory

Oxford's Clarendon Laboratory

Oxford's Clarendon Laboratory is a previously unpublished history written by AJ Croft in 1986. Croft was a cyrogenics expert and administrator in the Clarendon from the 1940s to the 1980s and the text is based on Croft's personal knowledge and extensive research – which included his own memories of, and interviews with, many of the great Oxford physicists of the early and mid-20th century.

The typescript was rediscovered and transcribed by Timothy Baker, son of the late Michael Baker of the Clarendon, and Mike Wells, a colleague of Croft's.

All views expressed in the original text are those of AJ Croft.