An extensive amount of information has been included in this short book about the oceans. The vast depths and distances of the waters and the complexity of air currents and tides are investigated first, followed by descriptions of marine life. The book then explains oceanography and the various ways in which the ocean has been explored, and the benefits obtained as a result of ocean study. The illustrations, done by the author, have been executed with careful draughtsmanship. Few of them are labelled, however, and they are generally much less informative than the text. This is a smoothly-written, well-researched introduction to the sea and its study, and underwater topics continue strong in reader interest for both fiction and non-fiction.