The explosion of interest, effort, and information about the ocean since about 1950 has produced many thousand scientific articles and many hun­ dred books. In fact, the outpouring has been so large that authors have been unable to read much of what has been published, so they have tended to concentrate their own work within smaller and smaller subfields of oceanog­ raphy. Summaries of information published in books have taken two main paths. One is the grouping of separately authored chapters into symposia­ type books, with their inevitable overlaps and gaps between chapters. The other is production of lightly researched books containing drawings and tables from previous pUblications, with due credit given but showing assem­ bly-line writing with little penetration of the unknown. Only a few books have combined new and previous data and thoughts into new maps and syntheses that relate the contributions of observed biological, chemical, geological, and physical processes to solve broadproblems associated with the shape, composition, and history of the oceans. Such a broad synthesis is the objective of this book, in which we tried to bring together many of the pieces of research that were deemed to be of manageable size by their originators. The composite may form a sort of plateau above which later studies can rise, possibly benefited by our assem­ bly of data in the form of new maps and figures.