254 



TRANSACTIONS LIVEEPOOL BIOLOGICAL SOCIETY. 



solution added in varying proportion to this is a deci-normal 

 solution of hydrochloric acid. On one or two occasions the 

 phosphate combination was utilised, one ingredient of this is 

 one-fifteenth normal primary potassium phosphate (acid 

 phosphate), the other one-fifteenth normal secondary sodium 

 phosphate (alkaline phosphate), mixed as above described. 

 The following table gives the results of the observations : — 



Seasonal Variations in Hydrogen Ion Concentration of 

 Sea- Water. 



Period of Year. 



Potential of Hydrogen Ion 

 Concentration colorimetrically 

 determined with Borate and 

 Hydrochloric Acid mixture, 

 and corrected for Salt Effect 

 (Sorensen). 



Potential of Hydrogen Ion 



Concentration, electro- 



metrically determined by 



hydrogen electrode method. 



November, 1912 



-8-13 

 -8-10 



-8-20 



- 8-37 



- 8-31 



- 8-30 



- 8-20 



December, 1912 



- 8-16 



February, 1913 



- 8-20 



April, 1913 



- 840 



May, 1913 





June, 1913 



- 8-35 



July, 1913 









The results of the experiments demonstrate two things, 

 first that the hydrogen-ion concentration for the Irish Sea in 

 the neighbourhoods tested is fairly low indicating a corre- 

 spondingly higher alkalinity ; secondly that the alkalinity is 

 increased in the spring and summer months. The variations 

 are too small to warrant any further deduction than this. 

 Such observations are excessively difficult to carry out, but 

 their trend is sufficient to confirm the results of the titration 

 experiments, namely that the alkalinity of sea-water is lowest 

 in winter and increases in the spring. 



