6C
   Twenty-One Balloons, The
   William Pene du Boris
   Puffin Books
   Paperback
   181
   6600
William Waterman교수는 balloon을 타고 샌프란시스코를 떠나 태평양을 건너가려고 하지만 운명의 장난으로 Krakatoa라는 곳에 착륙하게 됩니다. 그곳에서 Balloon에 대한 Krakatoa의 비밀을 배우게 되고, 만일 그곳을 빠져나갈 방법을 생각해내지 못하면 영원히 그곳에 머물러야 하는데...