but decided to return to Birmingham. He worked on nuclear forces, scattering, quantum field theories, collective motion in nuclei, transport theory, and statistical mechanics. Peierls had largely left solid state physics behind when, in 1953, he began collecting his lecture notes on the subject into a book. Reconsidering the way that the atoms in metal crystals are arranged, he noted an instability. This became known as the Peierls transition. Peierls built up the physics department at Birmingham by attracting high quality researchers. These included Gerald E. Brown, Max Krook, Tony Skyrme, Dick Dalitz, Freeman Dyson, Luigi Arialdo Radicati di Brozolo, Stuart Butler, Walter Marshal, Stanley Mandelstam and Elliott H. Lieb. An undergraduate school of mathematical physics was created. Peierls delivered the lectures on quantum mechanics, a subject that had not been taught at Birmingham before the war. In 1946 Peierls became a consultant to the Atomic Energy Research Establishment at Harwell. After Fuchs was dismissed from his position there as head of the Theoretical Physics Division in 1950, Maurice Pryce acted in the position in a part-time capacity, but when he went to America for a year on sabbatical, Peierls took his place. The position was finally filled permanently by Brian Flowers. Peierls resigned from Harwell in 1957 due to what he saw as a lack of openness in security vetting at the request of the Americans, which he felt indicated a lack of trust in him on the part of senior staff; but he was invited to rejoin in 1960, and did so in 1963, remaining as a consultant for another 30 years. Peierls became the Wykeham Professor of Physics at the University of Oxford in 1963. He remained there until he retired in 1974. He wrote several books including Quantum Theory of Solids (1955), The Laws of Nature (1955), Surprises in Theoretical Physics (1979), More Surprises in Theoretical Physics (1991) and an autobiography, Bird of Passage (1985). Concerned with the nuclear weapons he had helped to unleash, he worked on the Bulletin of the Atomic Scientists, was President of the Atomic Scientists' Association in the UK, and was involved in the Pugwash movement, and FREEZE, now known as Saferworld. Genia died on 26 October 1986. Peierls remained active, although his eyesight deteriorated. In 1994, he suffered a combination of health problems, including heart, kidney and lung problems, and relocated himself to Oakenholt, a nursing home near Farmoor, Oxfordshire.