246 Dr. Marcet on an Aluminous Chalybeate Spring 



§ XVII. Conclusion. 



On reviewing and connecting together all the foregoing results, 

 it appears that each pint, or sixteen-ounce measure of the aluminous 

 chalybeate, contains the following ingredients : 



Of carbonic acid gas three-tenths of a cubic inch. grains 



Sulphat of iron, in the state of crystallized green sulphat . 41,4 

 Sulphat of alumine, a quantity which if brought to the 

 state of crystallized alum, would amount to . 



Sulphatof lime, dried at 160° 



Sulphat of magnesia, or Epsom salt, crystallized 

 Sulphat of soda, or Glauber salt, crystallized 

 Muriat of soda, or common salt, crystallized 

 Silica 



31,6 

 10,1 



16,0 

 4,0 



107,4 



I am not acquainted with any chalybeate or aluminous spring, in 

 the chemical history of mineral waters, which can be compared, in 

 regard to strength, with that just described. The Hartfell water, and 

 that of the Horley-green spaw near Halifax, both of which appear to 

 be analogous to this in their chemical composition, and were consi- 

 dered as the strongest impregnations of the kind, are stated by Dr. 



now adtled, both the silica and alumine were rc-dissolvcd (for silica, just precipitated 

 from Its solution, and notdesiccated, is soluble in acid) ; and this solution being evaporat- 

 ed to dryness in a water-bath, by which means the silica parts with its acid and becomes 

 insoluble, the muriat of alumine was washed off by distilled water, and the silica re- 

 mained nudissolved. This method, though affording a very useful means of discrimi- 

 nation, must obviously be liable to inaccuracy as to proportions, when very minute 

 portions of silica are to be separated from considerable quantities of alumine. This 

 however was the process to which I trusted on a previous occasion (IX. 2), to free the 

 alumine from the silica which was mixed with it. 



