Iodine in the Mineral Waters of Saratoga. 243 



All the mineral fountains that have yet been examined in 

 this valley, and there are more than twenty, are found to pos- 

 sess uniformly, the same qualities, differing only in what is 

 usually termed their strength, or, in other words, in the quan- 

 tities of the articles which the water of each is found to hold 

 in solution. They belong to a class which may with propri- 

 ety be styled the acidulous saline chalybeate. The best 

 analyses agree in demonstrating that they contain the follow- 

 ing ingredients, viz. 



Carbonic acid. 



Muriate of soda. 



Carbonate of soda. 



Carbonate of lime. 



Carbonate of magnesia, and 



Carbonate of iron, together with a very minute quantity of 



Silica and alumina. 



The great efficacy of these waters in a variety of stru- 

 mous affections, for which their known properties did not very 

 satisfactorily account, gave origin to the conjecture, that they 

 might contain Iodine, and the fact of that substance having 

 been recently discovered in some of the mineral springs of 

 Europe, gave confidence to the opinion which led to an in- 

 vestigation ; as soon, therefore, as leisure would permit, an 

 examination was commenced, with a view to that particular 

 point, and the result of the following experiments will, I trust, 

 be considered as sufficiently conclusive on the subject. 



Having procured a quantity of the salts of one of these 

 fountains, soluble in distilled water, I dissolved thirty grains 

 of them in a weak solution of starch in cold water, and then 

 let fall into the solution a drop or two of sulphuric acid ; 

 this produced a slight effervescence and the liquor immedi- 

 ately assumed a deep purple tinge, — on suffering this to 

 stand at rest a short time, the color was precipitated with the 

 starch giving it the well known characteristic blue tinge. 

 The clear liquor was now turned off and the colored starch 

 placed upon the surface of a warm stove, when the color 

 was immediately dispersed. 



Having thus ascertained the fact of the existence of Iodine 

 in these salts, it became important to acquire a knowledge 

 of the manner in which it is combined and retained in the 

 water. 



Iodine may exist in a mineral water in the state of iodic or 

 hydriodic acid combined with either of the alkalies, potassa 



