Peter Kenny , educated at Birmingham and Oxford Universities , was employed by the National Coal Board (later British Coal), first as a research scientist then as manager of various engineering departments. At the time of his early retirement, he was British Coal s Reliability Manager, reporting to the Chief Engineer. Since then, he has taught mathematics and science subjects in colleges of further education, and as a private tutor. He is a Fellow of the Institute of Physics , Member of the Institute of Materials , a Chartered Physicist and a Chartered Engineer. He has published many technica