PRINCIPLES OF ASTRONOMY.

By Stanley P. Wyatt '42. Boston: Allyn and Bacon, Inc., 1971. Second edition. Profusely illustrated. 686 pp. $14.95.

The first edition was a standard choice for introductory courses in astronomy, particularly at a level somewhat above the purely descriptive; the second adds emphasis to physical interpretation of observed phenomena in the astronomical universe, "to emphasize the hows and whys as well as the whats," as the author states in the preface. This approach is ideal for well prepared non-science students in a "liberal arts" setting because it communicates not only the facts and phenomena of astronomy but also something of the methodology and some major principles underlying modern physical science. The need for courses oriented toward such communication becomes ever more urgent, and texts such as this are a clear step in the right direction. These considerations, in fact, have led Dartmouth to adopt Wyatt's text for its introductory Astronomy 2 this Fall.

The second edition also includes color plates of various astronomical objects to compete, one supposes, with other introductory texts containing beautiful and expensive prints. The cost of the text (about $15) leads one to question how much these plates actually add to its value. Color slides during course lectures could present pertinent scientific points, and references to other sources of these prints, which the student might wish to peruse and/or purchase, would serve the dual purpose of reducing the cost of the book and getting students into the astronomy stacks of the library or bookstore. Perhaps future editions could contain a separate color plate booklet to be purchased at the option of the student.

In a field growing as rapidly as contemporary astronomy, it is impossible to produce a completely current description, but Wyatt's book brings us up to date into early 1971, and a sufficiently sound framework of basic astronomy is constructed throughout that teachers will find it relatively easy to keep their students abreast of more recent developments.

Dartmouth Assistant Professor of Physicsand Astronomy, Mr. Mook teaches coursesin the Evolution of the Universe, Stars andStellar Systems, and Observational Astronomy.