Editorials
From The Critics
This 32-page book was written for elementary school children in order to convey to them some concepts about the nature of light and sound. The book is divided into small paragraphs, each highlighted by a title denoting the topic discussed. On many pages are boxes labeled "Science Essentials" that summarize the science content of those pages.The volume begins with light—how it originates from a change in energy and also how it can be changed into energy (e.g., solar cells). It discusses rays and shadows; the speed of light; seeing; transmission, absorption, and reflection; animal light, and lenses, mirrors, and fiber optics. The section on optical instruments examines microscopes, telescopes, and digital images, but the latter is too complicated a topic for the book to give much in the way of details. The colors of objects and flames (emission spectra) are considered, and the discussion of primary colors gives a brief description of printing in color and the use of colors by humans and by nature. The section on light concludes by mentioning light as electromagnetic radiation occupying a very small region of the total electromagnetic spectrum; it discusses how various portions of that spectrum are used in astronomy to study objects in our universe.
The next five pages of the book give a brief introduction to sound, the nature of waves, how sound differs from light not only in its nature, but in its speed, and how echoes are used by humans and animals to locate objects. Hearing and its attributes, loudness and pitch, are examined, and the dangers of sound are presented. The discussion of musical sounds is compressed into only two pages and would be very unsatisfying even forsome young readers. The book concludes with a glossary, a list of three books for further study, and an index. (from the Science Topics Series.) Highly Recommended, Grades 3-6. REVIEWER: Dr. Richard F. Schwartz (emeritus, State University of New York)