386 



DISCOVERY REPORTS 



Solubility of nitrogen in whale blood. So far comparison has been, made be- 

 tween the nitrogen volumes existing in whale's blood and the human solubility coefficient 

 for dissolved atmospheric nitrogen. The peculiar circumstance has been revealed of a 

 mammal having less nitrogen in solution than should have been dissolved normally in 

 accordance with established physical laws, even without high pressures which should 

 cause the solution of even greater volumes of gas. When, however, control experiments 

 were performed to ascertain the solubility of air nitrogen in whale's blood, it was found 

 that more than the expected i-20 vol. per cent were taken up. These experiments con- 

 sisted simply of exposing blood samples to air by shaking them in an open flask, both 

 at room temperature and at 36° C. Gas analysis was performed as for the original 

 sample. Variable results were obtained by this method, the full significance of which 

 was not realized until it was found that inevitable delay in manipulation influenced the 

 volume of residual nitrogen. A number of nitrogen "capacities", some of which 

 represent residual nitrogen in estimations of the oxygen capacity of the blood, are 

 shown in Table IV. Reagents used in oxygen estimations were, of course, carefully 

 evacuated and tested before introducing the blood into the burette. 



Table IV. Nitrogen capacity of whale blood from aeration followed by gas analysis. 



* 10 minutes' interval between aeration and gas analysis. 



It is evident that whale blood is able to take up more than the normal amount of 

 nitrogen from the air. The highest figure found by this method was 3-20 vol. per cent 

 in no. 40. The plasma of no. 7, which sedimented rapidly, was treated in the same way 

 in two separate experiments; the nitrogen capacity was in each case 3-14 vol. per cent. 

 Unfortunately not much attention could be paid to plasma for lack of an effective 

 centrifuge, but the results obtained with this sample indicate that the ability to hold 

 extra nitrogen resides in the plasma and not in the corpuscles, a conclusion which will 

 be substantiated in other ways later. 



