Underground Worlds - Planet Earth Author:Donald Dale Jackson Time Life's 'Planet Earth' series is always an enjoyable read. Engaging, with stunning color photographs, 'Underground Worlds' is a great catch-all caving book, and a good introduction to the underground. The book talks about caving all over the world (a refreshing change, as most caving literature in this country refers only to caves in the Wes... more »tern Hemisphere.) A large portion of the book is devoted to caving in Europe (where the systematic study of caves began) and more than one story ends in tragedy.« less