310 



THE OCEAN, 



If \ve were acquainted with the proportion between the saline con. 

 tents of sea water and its specific gravity, it would be easy i.i all 

 cases to ascertain the quantity of saline matter merely by taking the 

 specific gravity of the water we wish to examine. This would re- 

 quire a set oi experiments on purpose ; dissolving in pure water 

 different quantities of the salts contained in sea water in the propor- 

 tions which they bear to each other, and ascertaining the specific 

 gravity of every such solution. Dr. Watson has given us a Table 

 for ascertaining that point, as far as common salt is concerned ; and 

 as the salt which he used was not perfectly pure, but contained a 

 mixture of the different salts usually found in the sea, we may con- 

 sider it as very nearly determining the proportion of saline contents 

 in sea water as far as it gees. This Table therefore I shall here 

 insert *. 



This Table was calculated at a temperature between 46 and 

 55; but Mr. Kirwan has reduced part of it to the temperature of 

 62, in order to compare it with the specific gravities of sea-water 

 taken at that temperature, or at least reduced to it. The specific 

 gravities, thus altered by Kirwan, are as follows : 



Proportion of Salt. Specific Gravity at 62. 



1.24th 1'0283 



1.25th .. . 1-0275 



1.26th 1-0270 



1.27th 1-0267 



1.28th .1-0250 



* Watson's Chtmical Essays, p. 9J. 



