The story of Fred Wensley, a Somerset gardener who joined the Metropolitan Police in 1888 and retired, forty-one years later as Chief Constable of the CID, is an extraordinary one. After an abortive attempt to catch 'Jack the Ripper' by nailing strips of bicycle tyres to the soles of his boots, Wensley got stuck into arresting the ne'er-do-wells of Whitechapel, where he would spend twenty-five years of his service. Within months of joining...