George Johnson tells the stories of ten beautiful experiments which changed the world. From Galileo singing to mark time as he measured the pull of gravity and Newton carefully inserting a needle behind his own eye, to Joule packing a thermometer on his honeymoon to take the temperature of waterfalls and Michelson recovering from a dark depression to discover that light moves at the same speed in every direction - these ten dedicated men employed diamonds, dogs, frogs and even their own bodies as they worked to discover the laws of nature and of the universe.