When, oh when, will publishers adopt the practice of checking their science juveniles with the nearest available teacher? This book is labeled for the 10-14 age group, but its rather stilted style and difficult vocabulary (plus some mathematics) put it right up into the high schools. So do the experiments, some of which call for such skills as soldering, controlled heating of sulphur (sketchily described with no safety precautions) and assembling a ""simple"" Geiger counter about as simple as your radio. Bischof's Atoms at Work (Harcourt) is still best bet.