"Manipulation of the Microscope," Edward Bausch (Rochester: Bausch & Lomb Optical Co.). At this season of the year, when so many of our readers are interested in the study of botany and other nature work, the use of the microscope enters largely into their work—and yet how few people really understand this most useful instrument. The writer of this admirable little book very sensibly assumes that his readers are anxious to learn the subject from its simplest form to the more complex details, and he has therefore made a thoroughly useful book. Few people realize the delight of using a microscope intelligently, nor do they grasp the true value of even the simple pocket forms of this invaluable little instrument. If they did properly appreciate the microscope, every boy would carry a two or three loop lens, and find it as useful almost as the indispensable jackknife. The wonders of field, forest, and seashore are not thoroughly appreciated unless the microscope is used—intelligently.