Sunken treasure and deep sea diving -- the two elements of unity of the book. Otherwise, the author squeezes into this volume a miscellany of facts about treasure hunters: -- William Phips, the backwoodsman from Maine who retrieved the treasure of a Spanish hulk for Charles II; an account of the amazing salvage of the Niagara in 1941; the history of diving from the time of Herodotus; a list of unsalvaged treasures; a technical consideration of the future of deep sea salvage. By far the best section of the book is the author's account of his own diving experiences, the fantastic ocean floor, narrow escapes from sharks and octopuses, and the joy at finding treasure. It comprises far too small a part of the book. Not a book for a wide general market, but for armchair adventures of specialized interests.