1. The Oceans and Their History 



Xor thousands of years men have been scanning the 

 ceiling of our universe, the vaults of Heaven. The stars 

 in their courses have stimulated the imagination and 

 fostered belief in ultimate things. Today, thanks to the 

 magnificent resources of modern astronomical observa- 

 tories, especially in America, we are able to probe the 

 remotest spaces of our universe and study galaxies 

 separated from our own small world by hundreds of 

 millions of light-years. Modern physics has shown us 

 how to interpret the faint light signals transmitted to us 

 across enormous gulfs in space. 



On the other hand, the oceans around us were long 

 neglected. Five centuries ago explorers began to steer 

 their frail ships across the unknown ocean, discovering 

 new continents, but for obvious reasons their interest 

 was limited to the ocean surface, and the great depths 

 beneath remained unknown and unexplored until less 

 than a century ago. True, pioneers of the new science 

 of oceanography had made some earlier attempts to 

 learn how deep the ocean is, the temperature of the 

 water at great depths, and the character of the sediments 

 which carpet the ocean floor, but their tools of research 



