290 



of barytes formed to bromide and chloride of barium. 

 These salts were dissolved in water, deprived by carbonic 

 acid and boiling of free barytes ; again evaporated to dryness, 

 ignited., and accurately weighed. Water being poured on, 

 they were re-dissolved, and converted, by the addition of 

 nitrate of silver, into a mixture of the bromide and chloride 

 of silver, which was also accurately weighed. Now, if to be 

 the weight of the mixed bromide and chloride of barium, w' 

 that of the mixed bromide and chloride of silver, x the chlo- 

 rine, y the bromine, m the ratio of the atomic weight of chlo- 

 ride of barium to chlorine, n that of the atomic weight of 

 bromide of barium to bromine, m the ratio of the atomic 

 weight of chloride of silver to chlorine, and ri that of the 

 atomic weight of bromide of silver to bromine, we will have 

 the following equations : 



mx -\-ny — w, and m'x -f- n'y — w'» 

 from which we get 



m w — mw „. 



y — — — — .* 



mn — mn 



Having thus obtained the bromine, the chloride was easily 

 inferred from the mixed chloride and bromide of silver, al- 

 ready got by adding nitrate of silver to the water. The 

 following are the final results. 



Chloride of calcium, 2.438J 



Chloride of magnesium, 7.370 



Bromide of magnesium, 0.201 1 



Chloride of potassium, 0.852'y— 18.78. 



Chloride of sodium, 7.839 ' 



Chloride ofmanganese, 0.005 



Sulphate of lime, 0.075 



Water, 81.220 



100. 



* This method answers well, the atomic weight of bromine being so much 

 greater than that of chlorine, and is susceptible of far greater accuracy than any 

 more direct one, having for its object the insulation of the bromine. 



