It is the windiest, coldest, most forbidding region on earth, and I am heading straight for it. Sketchbook in hand, an artist leaves home to spend four months in Antarctica. She hikes up glaciers, camps on deserted islands, and sees mirages of castles in the air. She sails past icebergs and humpback whales. And she fills her sketchbook with drawings of penguin chicks huddled in their nests and seals basking in the sun. Jennifer Dewey's sketches, photographs,...