A lonely spire of stone rises from the rocky promontory of Bradda Glen on the Isle of Man, looming over the sleepy village of Port Erin and its namesake bay. While this dark tower might seem at home in a Stephen King novel, or a place to sequester a fairy-tale princess, Milner’s Tower was originally erected to honor (not imprison) a local philanthropist and benefactor. William Milner was a wealthy safemaker who moved to Port Erin from Liverpool in the mid-1800s to recuperate from an undisclosed illness. Trading the maddening…