In the past, radiation treatment planning has been a very lengthy procedure. Now, with the aid of CT therapy-planning computer programs, we can position the therapy beams automatically with precision in a few minutes.

I was born and brought up near a village in Nottinghamshire and in my childhood enjoyed the freedom of the rather isolated country life. After the First World War, my father had bought a small farm, which became a marvelous playground for his five children.

Don't worry too much if you don't pass exams, so long as you feel you have understood the subject. It's amazing what you can get by the ability to reason things out by conventional methods, getting down to the basics of what is happening.

The periods between my 11th and 18th years remain the most vivid in my memory because this was the time of my first attempts at experimentation, which might never have been made had I lived in the city. I made hazardous investigations of the principles of flight, launching myself from the tops of haystacks with a homemade glider.