Book excerpt: Science tells us grand things about the universe: how fast light travels, and why stones fall to earth. But scientific endeavour goes far beyond these obvious foundations. There are some fields we don't often hear about because they are so specialised, or turn out to be dead ends. Yet researchers have given hallucinogenic drugs to blind people (seriously), tried to weigh the soul as it departs the body and planned to blast a new Panama Canal with atomic weapons. Real scientific breakthroughs sometimes come out of the most surprising and unpromising work. How to Make a Tornado is about the margins of science - not the research down tried-and-tested routes, but some of its zanier and more brilliant by-ways. Investigating everything from what it's like to die, to exploding trousers and recycled urine, this book is a reminder that science is intensely creative and often very amusing - and when their minds run free, scientists can fire the imagination like nobody else.