I am not the first member of my family to leap over a wall. Nearly four hundred years ago, my ancestor, Thomas Baldwin of Diddlebury, leaped to freedom from behind the walls of the Tower of London, where he had been imprisoned for taking part in a plot for the escape of Mary Queen of Scots. His name, with an inscription and the date 'July 1585' can still be seen where he carved it on the wall of his cell in the Beauchamp Tower. Later, he added a motto...