2 



Chapter 



THE STRUCTURE OF THE ATLANTIC 



Th 



.HROUGHOUT their history people of the western world 

 have been familiar with the Atlantic — when they spoke or wrote of 

 "going to sea" or "crossing the ocean" it was upon the Atlantic 

 Ocean or some of its seas that they were about to embark. This was 

 first true of all Europeans and later became true also of settlers in Ice- 

 land, Greenland, Canada, the United States, the east coast of Central 

 and South America, the west coast of Africa. To millions of people, 

 to hundreds of thousands of families, to states and nations, the cross- 

 ing of the Atlantic became an important historic event and the Atlan- 

 tic their particular and almost personal ocean. 



This familiarity has its drawbacks. Today the word "Atlantic" 

 will bring to mind a different image for each different reader. To 

 some it will mean the heaving gray waters of a dirty but busy harbor; 

 others will think of a clean rocky cove in Maine with little islands in 

 the ofling; or a flat sunlit beach in Florida; or the standing waves of 

 Pentland Firth; or a harbor in Brittany that is over twenty feet deep 

 when the tide is in but is dry sand when the tide is out and the 

 ocean is just a blue line out there. Millions will think of it only as a 

 rather narrow strip of water connecting New York harbor with the 

 ports of the English Channel. 



Each of these is a true but very specialized view of some part of 

 the ocean. Clearly before we can describe the structure of the Atlantic 



