188 SEA FISHERIES 



charts alone will suffice, and you need not leave your 

 study. Wherever you find a zone in which warm 

 and cold waters mingle, it is ninety-nine to one that 

 you have hit upon a rich fishing-ground : a stretch of 

 sandy bottom, with here and there rocks and valleys 

 for the deep-water fish and shallower waters for the 

 rest. 



We may also expatiate upon the destiny of our present 

 fishing-grounds. We have only to remember that local 

 fluctuations are the result of phenomena which involve 

 the general economy of the whole globe. The physi- 

 ology of the Atlantic, and consequently that of the 

 Mediterranean, the Channel, and the North Sea, depends, 

 as we have said, upon the Gulf Stream. Now, the 

 existence of so formidable a current as the Gulf Stream 

 is related to the rotation of the earth. Plankton, that 

 inexhaustible reservoir of nourishment, is inevitable, and 

 as a whole constant. Its relations to the world of fish 

 are also constant. Thus the alimentary problem is being 

 constantly solved in the heart of the ocean, and the 

 sea produces neither more nor less than it can produce. 

 Fish, on the other hand, confined to the continental 

 plateau and subjected to hereditary instincts, voracious 

 and short-sighted, always hampered by their colossal 

 numbers (banks of menhaden, the American herring, 

 have been seen containing each more than 150 millions 

 of tons of fish !) fish, I say, are enclosed in a definite 

 net of circumstance ; they are accessible, and their 

 capture is easy. Consequently, failing some world- 

 shaking cataclysm, the existence of fishing-grounds is 

 assured. 



These are the results of observation ; now let us pass 

 to the results of experience. We shall find that the one 

 class of results verifies the other. The Fishery Board of 



