PREFACE 



The sea — inspiration to the poet and writer, challenge to the sci- 

 entist, battleground of militarists, adventureland of sportsmen — con- 

 tinues as one of the last great frontiers for man to conquer. The 

 sea has taken on new meaning as a military medium, with the in- 

 troduction of nuclear-powered submarines as launchers of guided 

 missiles. The development of new underwater detection mechanisms 

 has brought the importance of marine organisms and their sounds 

 into sharp focus. The detonation of thermonuclear weapons and 

 the dumping of radioactive materials has brought man into a new 

 and more intricate relationship with ocean currents, and with the 

 flora and fauna of the sea. The minute phytoplankton of the sea, 

 formerly of interest only to the bespectacled academician, threatens 

 to invade the domain of the politician in the new era of radioactive 

 uptake. The rapid expansion in human population, presently on an 

 upward spiral of more than 43,000,000 additional persons each year, 

 demands that the nutritionist re-examine man's protein larder. The 

 Food and Agriculture Organization of the United Nations officially 

 has declared that fisheries' products must be increased by nearly 

 90 per cent if we are adequately to feed the world's future popula- 

 tion. In the quest for new chemical agents, pharmacologists and 

 chemists are beginning to turn their attention to the vast untapped 

 resources of the sea. Even the sportsman has turned to the under- 

 water world with renewed interest and vigor. Yes, the ocean is 

 becoming of increasing importance to the health and welfare of 

 mankind. However, with the greater effort to penetrate the ocean 

 depths, to pry into the secrets of its creatures, and to harness its 

 mighty resources will come new problems which, all too frequently, 

 are accompanied by pain and death. 



One area of activity which has brought man into closer contact 

 with marine organisms in their natural environment than probably 

 any other is that of skin diving — be it professional, or merely for 

 pleasure. Skin diving has become one of the world's fastest grow- 

 ing sports. It is estimated that there are more than one million 

 skin divers in the United States alone, and still the field continues 

 to grow. Numerous deaths have resulted from diving — many of 

 which might have been prevented by adequate technical training. 

 Although skin diving can be considered as a sport, like flying, it 

 requires education, skill, and experience. 



Stories concerning dangerous marine organisms are legion. While 

 these hair-raising tales may be useful in holding an audience spell- 



