A walnut bookcase with three shelves hung on the wall of a country sitting room, and inside it lived everything that mattered: a coverless Vanity Fair, a maroon David Copperfield whose pages were limp with a child’s kisses, half of Rob Roy, and a fat P. T. Barnum autobiography won for saving a Jersey calf’s life. When the children reached the last shelf, they simply began again. What those twenty-odd volumes taught one girl about reading, imagination, and the books we owe our children is the subject of this spirited and deeply personal essay.