288 PROCEEDINGS OF THE AMERICAN ACADEMY 



The aqueous solution saturated at 18° therefore contained the follow- 

 ing percentages of the anhydrous salt : — 



I. II. 



9.97 9.98 



Plumbic jBy-DicMor-h-Sulphopyromucaie, PbCl5Cl2SOg . 3 II2O. 



The lead salt is readily soluble in hot water, more sparingly solu- 

 ble in cold water, and separates on cooling its concentrated aqueous 

 solution in masses of fine needles. 



I. 0.5342 grm. air-dried salt gave 0.3106 grm. PbSOi. 



II. 0.5524 grm. air-dried salt gave 0.3212 grm. PhSO*. 



III. 1.1523 grm. air-dried salt lost at 160° 0.1163 grm. HjO. 



IV. 1.2621 grm. air-dried salt lost at 160° 0.1286 grm. HjO. 



IV. 



10.19 



I. 0.4520 grm. salt dried at 160° gave 0.2910 grm. PbSO*. 

 II. 0.6342 grm. salt dried at 160° gave 0.4107 grm. PbSOi. 



Pb 



Potassic [Sy-Dichlor-h-Sulphopyromucate, K2C5CI2SO6 • H2O. 



This salt we made by precipitation with potassic carbonate from 

 the barium salt. It was readily soluble even in cold water, and crys- 

 tallized in needles which contained one molecule of water. The air- 

 dried salt lost nothing over sulphuric acid. 



I. 0.6161 grm. air-dried salt gave 0.3017 grm. K2SO4. 

 II. 0.6722 grm. air-dried salt gave 0.3299 grm. K2SO4. 

 III. 1.4226 grm. air-dried salt lost at 160° 0.0686 grm. H2O. 



Ill 



4.82 



I. 0.6218 grm. salt dried at 160° gave 0.3200 grm. K2SO4. 

 II. 0.7197 grm. salt dried at 160° gave 0.3688 grm. K2SO4. 



Calculated for Found. 



K.,C5Cus0e I. n 



K 23.19 23.10 23.01 



