Stewart Brooks is concerned not with that other sea around us but within us: water makes up 97% of the embryo, 90% of the infant, 60% of the adult. Two-thirds is cellular, one-third intercellular, and it flows in and out of the cells in a balanced way (by osmosis), in and out of the body in balance as well (with an intake of fluids, preformed and oxidated water). There is also the acid-alkali balance measured by the Ph scale (7.4 is normal) to consider. Man at sea in the desert or upon the ocean faces thirst/dehydration: and Mr. Brooks explores how it is that a camel can survive in the Sahara when man cannot, how a seabird deals with saltwater. He describes the ills that involve the element: burns and blood pressure, elephantiasis, glaucoma, hydrocephalus, diabetes, kidney and blood diseases. Mr. Brooks has written several basic fact books in the medical field; this preps at that level of information.