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62 On the Analysis of 
tially limy or alkaline by the colour tests, 
And this alkalinity is not destroyed till some 
more powerful acid, such as the sulphuric or 
muriatic is added, sufficient to saturate the 
whole of the lime. Indeed these acids may 
be considered as sufficient for tests of the 
quantity of lime in such waters, and nothing 
more is required than to mark the quantity of 
acid necessary to neutralize the lime. It does 
not signify whether the spring water is boiled 
or unboiled, nor whether it contains sulphate 
of lime along with the carbonate, it is still 
limy in proportion to the quantity of carbonate 
of lime it contains. Agreeably to this idea 
too I find that the metallic oxides, as those 
of iron or copper, are thrown down by com- 
mon. spring water just the same as by free 
lime. Notwithstanding this, carbonate of 
lime in solution with water, contains twice 
the acid that chalk or limestone does. I fully 
expected the supercarbonate. of lime in so- 
lution to be acid. But it is strongly alka- 
‘line, and scarcely any quantity of carbo- 
nic acid water put to it. will overcome this 
alkalinity. Pure carbonicacid water is, how- 
ever, acid to the tests. I could not be con- 
vinced of the remarkable fact stated in this 
paragraph, till I actually formed superearbo- 
nate of lime, by supersaturating lime water 
