MINERAL WATERS OF DUNBLANE. 487 



Cheltenham, by the addition of a httle sulphate of magnesia, 

 or more nearly, by the addition of a little of the bittern of sea 

 water ; and where in the use of these waters, a continued pur- 

 gative operation is required, such an addition might always be 

 made with advantage. They might even be made to receive 

 the impregnation of carbonic acid of the Cheltenham water, 

 by adding the magnesia in the state of carbonate, with the due 

 proportions of sulphuric and muriatic acids in a close ves- 

 sel. 



The water of Harrowgate affords in its saline ingredients 

 another illustration of the same views. The principal ingre- 

 dient is muriate of soda, with which are present muriate of 

 magnesia, muriate of lime, sulphate of magnesia, carbonate of 

 magnesia, and carbonate of lime. Now nothing is more pro- 

 bable, than that the two last substances ax-e not original ingre- 

 dients, but are products of the analysis formed by the action 

 of carbonate of soda existing in the water on portions of its 

 muriate of magnesia and muriate of lime, whence also the 

 quantity of muriate of soda is increased. 



Lastly, A similar view may be extended to some of the most 

 celebrated foreign mineral springs. Those of Spa, Pyrmont, 

 and Seltzer form a very valuable order of mineral waters, to 

 which we have none analogous in this country; — what have been 

 called the alkaline carbonated waters, distinguished by the 

 leading character of being largely impregnated with carbonic 

 acid gas, and containing a considerable proportion of carbonate 

 of soda. With this are associated carbonate of magnesia, car- 

 bonate of lime, and muriate of soda. Now this association of 

 muriate of soda with these earthy carbonates, while there is al- 

 so carbonate of soda present, leads almost necessarily to the 

 belief, that the real ingredients are carbonate of soda, muriate 

 of magnesia, and muriate of lime; that the carbonate of soda 



3Q2 is 



