MINERAL WAFERS OF DUNBLANE. 449 



The saline taste of the water, and the precipitation so abun- 

 dant by nitrate of silver, render probable the presence of mu- 

 riate of soda, and it is accordingly obtained, when the water 

 is evaporated nearly to dryness, cubical crystals of it forming 

 in the saline liquid. 



From the whole, therefore, the principal ingredients of this 

 water may be inferred to be muriates of soda and lime, with a 

 smaller portion of a sulphate, and a minute quantity of iron. 

 These conclusions suggested the following methqd of ana- 

 lysis. 



An English pint of the water was evaporated to dryness j 

 and the solid residuum was exposed to a heat approaching to 

 redness, until it became perfectly dry. It weighed while warm 

 47 grains. It quickly attracted moisture from the air, so that 

 its surface >soon became humid, and on leaving it exposed for 

 twenty-four hours, a considerable portion was dissolved, form- 

 ing a dense liquor, while a portion remained undissolved. 



The whole solid matter being rendered dry, was submit-, 

 ted to the action of alkohol, with the view of separating by so- 

 lution the muriates of soda and lime, of which it was supposed 

 to be principally composed. It is well known, that this me-, 

 thod is liable, in some degree, to two sources of error ; the one, 

 that a little muriate of soda is dissolved by the alkohol with the 

 muriate of lime ; the other, that even when a large quantity of 

 alkohol is employed, the undissolved muriate of soda retains a 

 small portion of muriate of lime. In estimating the quanti- 

 ties from the results, these errors, indeed, in some measure^ 

 counterbalance each other ; but still they may exist in different 

 degrees, according to the quantity and strength of the alkohol, 

 and it is necessary therefore to obtain perfect precision, to ob-r 

 viate them as far as possible. 



