ATMOSPHERIC CASKS IN SKA-WATI-k 97 



variation in the solution of atmospheric gases in sea-water has 

 been studied by Fraulein Loven. Al^a* in darkness can 

 absorb all the oxygen present, and arc able to live in oxygen- 

 free water for sixty to seventy hours. Cod and Whiting kept 

 in an aquarium for six hours reduced the oxygen from 5'i8 c.c. 

 to 0*19 c.c. (in i8J litres), and increased the carbonic acid from 

 39-56 c.c. to 44*17 c.c. At this stage they died. 



Smaller fish can endure a reduction of oxygen to o ! 8 c.c., 

 and will survive if afterwards they are placed in normal sea- 

 water. Broadly speaking, in the presence of sunlight zoo- 

 plankton increases the carbonic acid in sea-water, while the 

 phytoplankton lessens it. 



The chief cause of variation in the amount of carbonic acid 

 in the sea is the atmosphere. Estimates have been made of 

 the total amount of carbonic acid present in the sea and in the 

 atmosphere respectively, and it is calculated that the former is 

 twenty-seven times as great as the latter. There is almost 

 certainly an exchange of carbonic acid between the sea and 

 the air, dependent on the vapour tension of the carbonic acid 

 in the sea and air respectively to one another. It has been 

 calculated that the enormous pollution of the atmosphere 

 produced by the burning of coal (780 million metric tons 

 were consumed in 1901) is more than absorbed by the 

 sea, which therefore acts as a regulator of carbonic acid in 

 the atmosphere. The vapour tension of the carbonic acid 

 in the air is less over the oceans and their coasts than over 

 the land. 



When a comparison is made of the volume of carbonic acid 

 in sea-water, and when the variations are referred to their 

 probable causes, it is found there are three Salinity, 

 Temperature, and the Plankton. 



The International investigations show clearly that the 

 amount of carbonic acid present is directly dependent on the 

 salinity. 



