Why is glass transparent? Why do cats purr? Why do men have nipples? These are but a handful of the thousands of questions that over the years have been asked and answered in The New York Times Science Q&A column. At last, the best and most interesting of these questions-along with their answers-have been collected in a book for general readers. 50 illustrations | The New York Times Book of Science Questions & Answers by C. Claiborne Ray, Paperback | Indigo Chapters