Physical Techniques in Biological Research, Second Edition, Volume I, Part A: Optical Techniques focuses on the methods and theory applied to relatively pure preparations of biological substances that are derived from cells or other tissue elements. This book covers a wide variety of nonoptical techniques. Organized into five chapters, this edition begins with an overview of the fundamental principles of operation of optical instruments that can be explained in terms of the simple operations of lenses or light rays. This text then examines the limits imposed on direct observation, either through an optical instrument or with the unaided eye, by the nature of light itself. Other chapters consider the potential of certain other microprobe methods. This book discusses as well the process of molecular spectroscopy. The final chapter deals with optical rotation and its dependence on wavelength. This book is a valuable resource for biologists, scientists, physicists, physical chemists, and research workers.