100 SEA FISHERIES 



Brandt has shown that it receives annually per cubic 

 metre 14*85 milligrammes of azote in combination and 

 available for use (7*8 milligrammes from the rivers, 6*3 

 from the rains, and 75 from the sewage of cities), or 

 in all 487 millions of kilogrammes (nearly half a million 

 tons), while the tribute taken in the form of comestible 

 flesh amounts only to 16 millions of kilogrammes, 

 corresponding to 875 millions of fish captured. 



We have now briefly yet thoroughly considered all 

 the principal elements of the life of the fish. We 

 have dealt with the fish, its needs, and its instincts ; we 

 know where and in what manner it can find in nature 

 the means of satisfying them. The fishing-ground is 

 now a thing of perfectly definite qualities ; it is a 

 relatively shallow region, slightly broken by hollows 

 and valleys, and rich in foodstuffs. Moreover, all the 

 data which we have been considering have been 

 furnished by Nature herself, and it is Nature that we 

 have watched at her work. We must now return to 

 man, and must ask ourselves what part he plays in 

 the economy of the ocean. 



