The heroic true story of one of the Eastern seaboard's first woman lighthouse keepers, illustrated by a Caldecott Medalist. Living in the isolated Robbins Reef Lighthouse, overlooking turn-of-the-century New York Harbor, Kate Walker spent her life minding the light, keeping passing ships from running aground on the dangerous shoals. Originally the assistant to her lighthouse keeper husband John Walker, after his death Kate convinced the Lighthouse Board that she was able to manage the hard work on her own.    For more than three decades, Kate lived a solitary life, often totally isolated from the mainland by rough seas and dangerous storms. Tending to the lamps and ringing the heavy warning bell, she helped ships avert disaster-- and saved many sailors from the cold, choppy waters when disaster struck.   Elizabeth Spires describes the joys and hardships of a life at sea, detailing pivotal moments in Walker's life to show her indomitable spirit, and celebrates the determination that drove Kate to keep her home and her livelihood.  Paired with Emily Arnold McCully's atmospheric, vivid watercolor-and-ink illustrations of lonely lighthouses, sun-dappled afternoons, and wrathful storms, this gripping picture book brings turn of the century New York to life.   Additional material in the back of the book includes a biographical note about Kate Walker, historical photographs of Kate and her home at Robbins Reef Lighthouse, reproductions of an historical map of New York Harbor, and a list of sources for more information.