An exhaustive reference book--still another in this new, uneven series--whose author, an otolaryngologist, isn't quite sure whom he's addressing. The purpose is to explain common ear, nose, and throat ailments, their prevention, and treatment. Farb first discusses the normal anatomy and physiology of the area, then goes over such problems as colds, sinus troubles, nosebleeds, allergies, sore throats, motion sickness, hearing loss, and cosmetic nose surgery. He includes the correct way to blow one's nose (the alternative, sniffing, is safe and effective); tells what over-the-counter drugs can be taken for what; and advises a gram a day of vitamin C for those who are prone to colds. Though his explanations are generally understandable, Dr. Farb has a tendency to drift away from the reader (migraine sufferers, he writes, ""are often tense individuals who function in stressful situations, some of which are created by their perfectionist, obsessive-compulsive personality traits""). And he occasionally takes on the tone of a medical text: ""In evaluating the tonsillectomy candidate, be sure that the episodes counted really represented tonsillitis, with high fever, pus on the tonsils, enlarged neck glands, or group A beta-hemolytic streptococcal infections."" These lapses aside, there is a load of information on a precisely delineated area here; chronic sufferers will find everything they need to know.