Overview: First of an eight-part series in which Adam Hart-Davis cycles around the country in search of the unsung heroes of science. He visits south-west England, where his subjects include William Murdock, who devised the world's first mechanical vehicle and also came up with the idea of gas lighting, and the tragic Henry Winstanley, who amazed critics by building Eddystone Lighthouse in the seas off Plymouth, only to perish with his creation in a storm.