Welsh miners’ sons in physics Reading an article Death threat to scientists over Big Bang test, I learn that one of the leading figures behind the experiment is Lyn Evans, the son of a miner, whose fascination with science started as a boy, when he would create small explosions with his chemistry set at his council house in Aberdare, South Wales. Some years ago I attended a talk given by Sir John Meurig Thomas, FRS, himself a miner’s son from South Wales. He told us of the following incident which contributed significantly to Britain’s radar advantage in the Second World War. Here is a short account of how it happened, taken largely from Maurice Wilkins - The Third Man of the Double Helix: An Autobiography (Paperback ISBN 019280667X) “Sir John Randall (under whom Wilkins worked for a time after the War) ... could see no way of giving a magnetron the huge power that was needed if radar were to work effectively, but on holiday in Aberystwyth (Wales again!) in 1940, he bought a book in a second-hand bookshop that described (in German) how Hertz had discovered radio waves by making an electric current oscillate in a simple loop of copper. This led Randall to think that if a circular hole were made in the copper body of a magnetron, high current could be made to travel round the hole as it had in Hertz's copper ring. With a number of circular cavities in the body of the magentron, very high energies could be emitted. Besides radar, it is also the key component of microwave ovens.” (Ironic, isn’t it – a German book helping us to survive the onslaught of that nasty little man with a moustache!) Sir John Randall was English, but his mother was the daughter of a colliery manager, and his wife the daughter of a colliery surveyor. Coal mining everywhere!