The author's scientific explanations and descriptions are clear and finely written, she has the colorful, artistic approach of Rachel Carson to the sea and sea's edge. The sea and its creatures appear before the reader like a brilliant, 3- dimensional picture. The author's effort is matched by that of the artist, Elinor Jaeger, whose careful black and white sketches are a handsome complement. Unfortunately, the author did not realize that it was not necessary -- or to the book's advantage-- to approach intriguing factual material through a fictional gimmick. The two children who gain superhuman powers (they swim under sea and can breathe like fish; they are granted microscopic vision, etc.) only interfere with the author's presentation of interesting information which would have been able to stand alone.