154 SEA FISHERIES 



the following ensues : since the fate of the azote depends, 

 if I may say so, on the action of the nitrifying and 

 denitrifying bacteria, we ought to look into the condi- 

 tions capable of accelerating or checking this bacterial 

 activity. Do not believe that such a process is merely 

 a chimera : Professor Brandt has shown that the quantity 

 of nitrates and nitrites diminishes in summer 1 because 

 decomposition is accelerated, and that the addition of 

 phosphate of calcium to sea-water causes a very notable 

 increase of vegetable plankton. It would therefore be 

 possible to "fatten" or "manure" a given area of the 

 ocean as we fatten a field, or rather as we transform a 

 prairie naturally exhausted into productive tilth. It is 

 needless to say that this idea is in the region of pure 

 theory ; but this is no reason why it may not one day be 

 put into practice. 



Let us now return to realities. It is essential for the 

 fisherman that we should be acquainted with the sea and 

 the biology of the edible species of fish, and the necessary 

 researches are long and difficult, such as only trained 

 scientists can undertake. For this reason Sweden, in 

 1899, convened an international conference for the study 

 of the North Sea. England, Germany, Norway, Den- 

 mark, Holland, and Russia responded to the invitation. 

 The conference instituted a series of experiments for a 



1 Quantities of ammonia and of azote in a litre of sea-water. 



AZOTK. AZOTE. 



(In the form of (In the form of 



Ammonia.) Nitrates and Nitrites.) 

 Milligrammes. Milligrammes. 



(February ... '068 '199 



May '065 "170 



August -057 ... -095 



(February ... '063 '216 



North Seaj May -065 -217 



(August '061 '079 



Brandt, Conseil perm, inter, explor. de la mer, iii. 1902-4. 



