This is an up to date survey touching on every aspect of science's attack upon the question, "What is Life?" Written by one of the masters of scientific writing for the layman, it is a model of logical arrangement and natural integration of information that can stand as an example for all writers trying to "explain" scientific process and ideas. Its ease of comprehension is remarkable, yet the author's clarity is not dependent upon oversimplification. He has divided the complex story into four parts, and proceeding from the most familiar to the least, on an historical basis, he tells first of the development of species, then the cell, the molecule, and finally discusses the origin of Life. Interweaving facts from taxonomy, evolution, genetics, bacteriology, biochemistry, etc., he is always clear, never hesitating to define if necessary or detour to explain. Here the reader is told of the newest boundaries in the search, from what kind of life exists on Mars to the surprising facts about nucleic acid. An important book for all libraries having the slightest interest in providing the best in scientific explanation to the general reader--adult or teen age.