266 Mr. Brande on the Mineral Waters of Windsor. 



From the preceding statement it appears, that the substances 

 present in a pint of the stronger water are as follow : — 



Grains. 



Sulphuric acid . ... 33.00 



Muriatic acid . . . 21.00 



Carbonic acid . . . . 00.98 



Magnesia . . . . 21.25 



Soda ..... 10.52 



Lime . . . . 1.25 



88.00 

 Various opinions may be formed respecting the nature of the 

 saline combinations resulting from the union of these proximate 

 elements. From the successive separation of the saline contents 

 during the evaporation of the water, I am induced to consider 

 them arranged as follows, forming the solid contents of a pint of 

 the water, viz. : 



Grains. 



Sulphate of magnesia . . 38.0 



Muriate of magnesia . . . 24.5 



Common salt . . . .9.3 



Sulphate of soda . . . 10.8 



Sulphate of lime . . . 3.0 



Carbonate of soda . . . 2.4 



8S.0 

 The singular property of this water, that when boiled it throws 

 down carbonate of magnesia, appears to depend upon the action 

 of the carbonate of soda, which, though compatible with the earthy 

 salts in a cold and dilute solution, decomposes them at a boiling 

 heat, or when concentrated by evaporation. This has been verified 

 by artificial imitations of this mineral water ; and it has even been 

 found that sesqui-carbonate of soda, in such excess as powerfully 

 to redden turmeric paper, is compatible, not only in solutions con- 

 taining the salts of magnesia, but also in those holding the more 

 soluble salts of lime. In both these cases, precipitates are ob- 

 tained by boiling, and by evaporation — otherwise the solutions 

 remain transparent. 



