200 DESCRIPTIVE MINERALOGY. 



But in regard to troublesome impurities, viz. the chlorides of calcium and magnesium, the 

 proportion in the brine just described is much larger, as will appear from the following state- 

 ment: 



ORAim. 



Earthy chlorides in 100 grains of this brine, 9, 82 



Ditto in 100 grs. best Sjrracuse brine, 1.50 



Ditto in 100 grs. best Montezuma brine, 2.40 



The manufacture of salt from this brine, therefore, will require more than ordinary care ; 

 as the earthy chlorides, even in small proportions, render it moist, and unfit for certain uses. 

 The following is a summary of the most important facts in regard to this brine : 



1. It is the most highly charged mineral water heretofore found in the State. 



2. It contains a larger proportion of common salt than any of the brines previously obtained 

 at Montezuma. 



3. The impurities are in much larger proportion than in any of our brines. 



HYDRIODATE OF SODA. 



This salt, more properly perhaps the Iodide of Sodium, which exists in many of the foreign 

 springs, has been detected in some of those at Saratoga. It is one of the ingredients which 

 is supposed to impart peculiar medicinal virtues to these waters. 



Description. A neutral compound, deliquescent in the air, soluble in water and alcohol. 

 It fuses readily by heat, and is volatile, though less so than iodide of potassium. When its 

 solution is evaporated at the temperature of about 123° Fahr., it crystallizes in cubes, which, 

 according to Berzelius, contain 20 . 23 per cent, of water. 



The presence of iodine in this salt may be determined by adding to its solution, previously 

 acidulated with sulphuric acid, a cold solution of starch. A deep blue precipitate will be 

 produced, if any iodine is present. 



The Hydrohromate of Soda, or Bromide of Sodium, has been detected in several of the 

 foreign springs, and probably exists in the brine springs of Onondaga county, as bromine is 

 knovra to be one of their constituents. It is found only in very minute proportions. 



