'[An] irresistible account of a child's imaginary 8,000-mile journey through the earth to discover what's inside. Facts about the composition of the earth are conveyed painlessly and memorably.' --SLJ. 'An exciting adventure. . . . Illustrations [by Caldecott Medal winner Marc Simont] explode with color and action.' --CS. Best Books of 1979 (SLJ)Children's Choices for 1980 (IRA/CBC)A Reading Rainbow Selection