eS ees ae 
OF SEA-WATER. 231 
-» This principle, if just, is an. important one, as enabling us 
to determine the state of binary combinations in a saline li- 
quor. I add, therefore, one other illustration of the reasoning 
on which it rests. ott 
Suppose that in 2 compound saline solution, that is, one 
containing more than one acid and one base, the acid and ‘the 
base which have the strongest attraction, are those which aire 
most soluble, or form the most soluble compound ; the solvent 
power of the liquid operating at the same time, will concur 
with this, and favour their combination ; and any other acid 
and base likewise present, will of course, at: the same time, 
combine. But suppose the more powerful attraction to belong 
‘to those which form an insoluble compound, the solvent power 
counteracts this, and prevents the combination. And the 
more this power is increased, which is done by increasing the 
quantity of the solvent, the more will this be counteracted. 
‘The reverse combinations will therefore be established by the 
operation of the opposite affinities. Hence, generally speak- 
ing, in a dilute solution, the binary combinations must be 
‘those which form the most soluble compounds, and very pow- 
erful attractions would be required to counteract this. 
Applying this principle to the composition of sea-water, or 
rather to the question with regard to the sulphate of soda, and 
sulphate of magnesia, it is obvious, that the former is to be 
considered as the original ingredient, and the latter as a proe 
duct of the evaporation ; for muriate of magnesia, and sulphate 
of soda, are, on the whole, more soluble in water than muriate 
of soda and sulphate of magnesia. On the same principle it 
follows, still more unequivocally, that. the lime exists in the 
state of muriate of lime, with a portion of sulphate of ‘soda 
equivalent to the quantity of sulphate of lime which \the,eva- 
7 poration affords. The salts, therefore, really existing in)sea- 
water, 
