The amateur touch for water boys, girls -- and babies- lends a lot of enthusiasm to this family record of diving and totals a vast amount of hobby satisfaction. Florida, California, the Bahamas, France and Corsica all provided different grounds for progress -- from the undependable hood, to the possibilities of skin diving, with improvements all along the way; still and movie cameras offered their special types of obstacles; marine life gave way to sunken treasure when cannon, coins, ivory, shipwrecks took over their interests. And as the four children grew older there was time out for sea school in the Tortugas and the happy holiday on Andros, in the Bahamas. The Criles give an intense picture of shapes in the sea, of their absorption over twenty years in underwater discoveries, of the excitement of the unexpected and their ability to take the good with the bad, and they share their delight in a most friendly way. For a less scientific audience than the Cousteau and Diole books, this should have a good family response.