190 THE OCEAN RIVER 



the lighter, warmer water shifts to the right and the heavier 

 and colder to the left. As the great North Atlantic circle of 

 water speeds up it draws the warm water inward, toward the 

 Sargasso Sea, but when the flow slackens the reverse takes 

 place and warm water spreads outward over the surface toward 

 the Arctic fronts. Though it has never been definitely proved, 

 it is at least likely that a faster Gulf Stream may mean less 

 warm water in the marginal seas of the northeast Atlantic. 



Science still has much to learn about these complicated 

 actions and interactions, but in the meanwhile there have 

 been many occasions to remind us that they exist. Since 1929 

 the sea around Greenland has become warmer and codfish 

 have moved in where they were scarce before. Warm and cold 

 years in the Norwegian Sea affect the appearance and disap- 

 pearance of shoals of fish; they alter the growth of trees and 

 they change the harvest of the dry land. Coral reefs, typically 

 tropical growths, exist in Bermuda far north of a limit beyond 

 which they would quickly die were it not for the Gulf Stream. 

 And in 1882 a change in the position of the Gulf Stream 

 caused the death of more than a billion tilefish. 



In the latter part of the nineteenth century a new fishery 

 was discovered off the coast of southern New England, in 

 waters between 50 and 100 fathoms deep on the western bor- 

 der of the Gulf Stream. The jubilant fishermen aboard their 

 Gloucester schooners rapidly developed this windfall — and 

 with good reason, for their lines and hooks brought in tile- 

 fishes of 10 to 50 pounds with flesh every bit as good as cod. 

 In March of 1882 the fishery completely disappeared. Vessels 

 crossing this part of the ocean reported dead fishes covering 

 the surface as far as the eye could see during nearly two days 

 of steady sailing. The terrific mortality took place over an area 

 of 7,000 square miles, and estimates have placed the number 

 of dead fishes at over one billion. At the time of the calamity 

 there was an unusually strong run of the cold Labrador cur- 



