The divers of the French Navy have written-and are writing-undersea history, and each book about their achievements seems more thrilling than the last. Cousteau's The Silent World brought Jules Verne up to date; Diole's 4000 Years Under the Sea gave underseas exploration its place in scientific archaeology. Scott, with 70 Fathoms Deep immortalized the new field of buried treasure -- and there have been others. Tailliez as Commander of the Undersea Research Group brings virtually all phases of the accomplishment together, reviewing some of the material in the other books (little about the archaeological aspects), but extends the field to include lesser known exploits such as the descent into the Fountain of Vaucluse (where the divers nearly lost their lives), and the varied experiments in the waters of Indo-China where numerous war vessels were sunk with valuable metals on board. The near-tragedy of the Picard bathyscaphe adventure, the making of underwater films, including Sunken Ships, and the post-war challenge in the removal of mines all contribute to a record of a whole new field of research, barely touched but opening new vistas. The beauty, the danger, the fascination comes out in every page. One would feel that this should follow reading of earlier books on the subject, for there is assumption that terminology and procedure and current inventions relating to this ""silent world"" are familiar to the reader.