A WALK FROM THE WILD EDGE by Jake Tyler (Michael Joseph £16.99, 320pp) ‘The moment my legs begin to move, my thoughts begin to flow,’ writes Henry David Thoreau. The quote appears in Robert Martineau’s Waypoints, an account of his own experience of taking a walk to cure depression. Tired of long hours at his desk in a London law firm, the 27-year-old flies to Ghana, and starts putting one foot in front of the other. His stroll ends up covering 1,000 miles and three countries. He sees men with scars across their cheeks: ‘Without doctors, people sew herbs into their faces to fight illness.’