150 color photos 36 drawings Colorful, fact-filled reference This basic guide makes optimum use of color photos and instructional drawings to present the essentials of diving. It begins with a clear, concise explanation of the science of diving-how water and gas affect the human body underwater-and includes chapters on equipment, training, dive planning, safety, and the various types of diving. Step-by-step photos and drawings, along with straightforward text, illustrate concepts and techniques with exceptional clarity. Jack Jackson is a veteran diver and author of several books on diving. An advanced BSAC diver, he has spent decades exploring the ocean.