Keeper of the Nuclear Conscience: The Life and Work of Joseph Rotblat

When scientists attempt to play international politics, it usually ends in tears. The physicist Jo Rotblat, one of the first physicists to work on the Bomb, was one of the few to have bucked the trend and influence the thinking - and actions - of governments on nuclear disarmament. Having braved decades of frustration, and a stream of condescending insults from leading politicians and commentators, he became a hero to many physicists as - in the words of Andrew Brown's felicitous title - "keeper of the nuclear conscience".

In Brown, a radiation oncologist, we have the ideal author for a biography of this admirable man. He has written the lives of both James Chadwick, discoverer of the neutron, and the polymathic crystallographer J.D. Bernal, with an impressive thoroughness and enviably fair judgement. He brings these strengths to this project, making use of the recently released Rotblat papers in the Churchill Archives Centre.

Rotblat began his career in his native Poland as an experimental nuclear physicist of enormous promise. In early 1939, when he was 31, he joined Chadwick at the University of Liverpool as a researcher, impressing him with his skill and ingenuity. Hitler's invasion of Poland led Rotblat to settle in Britain and to become separated from his wife, whom he never saw again. Terrified that the Nazis might be the first to build a Bomb, he willingly joined the British nuclear effort and in February 1944 transferred to Los Alamos to work on the Manhattan Project. He was not there long. When he heard General Leslie Groves remark that the real purpose of the project was to subdue the Russians after the war, Rotblat was disillusioned - irrevocably so, after he learned that the Nazis had no chance of making the Bomb. By the time of the strikes on Hiroshima and Nagasaki, he had long returned to Britain, where he later changed fields to medical physics and moved to St Bartholomew's Hospital in London.

What made him a great and intriguing figure was the leading role he played as co-founder of the Pugwash organisation, which brings together scholars and public figures with the aim of reducing the dangers of armed conflict, notably nuclear war. Rotblat is a difficult subject to write about: he had a somewhat peppery manner and could occasionally rise to anger, but was all but devoid of peccadilloes, was uninterested in becoming a celebrity and led a blameless personal life. His only passion, it seems, was to promote the aims of his organisation and so allow us to sleep more safely in our beds.

Given these limitations, Brown has done a fine job of writing Rotblat's life and of giving us a potted history of Pugwash. The author obviously has a profound admiration for his subject and often refers to him by his first name - in my view an unfortunately chummy biographical practice, although it does not mar our enjoyment of the book.

Brown relates in some detail the history of Pugwash, an organisation that, although well intentioned, was sometimes poorly led and did not always play its hand wisely. That said, there can be little doubt the committee that awarded the 1995 Nobel Peace Prize to Rotblat and Pugwash chose well.

I met Rotblat once, at the end of a colloquium in London. We shared a taxi and, during the journey, he suggested we have lunch. I declined, pleading an obligation to attend some footling meeting. Brown's rich, rewarding book has made me appreciate how unutterably foolish I was.