These series" entries feature attractive spreads filled with eye-catching illustrative materials and clear, concise writing. Invention surveys major areas of technology throughout history, with each spread showing the stages of development in one field (e.g., timekeeping, metalworking). Most captions include the approximate date of the invention pictured, but some years are not given, making it occasionally difficult to trace how each new step evolved. In Weather , the imaginative use of photographs helps to clarify many of the concepts. Reptile stands out because of the fascinating photographs, which are brilliantly lifelike and well chosen to demonstrate concepts discussed, educating readers in a way that words (or mediocre illustrations) cannot. The text is nicely balanced between straightforward factual data and intriguing bits of trivia, making the book useful both to browsers and report writers. Both gems and crystals are noted briefly in Symes"s Rocks & Minerals (Knopf, 1988)...