OP ARTS AND SCIENCES. 



11. 0.8009 grm. of the anhydrous salt gave on ignition with H^SO^ 

 0.2192 gin. BaSO,. 



The solubility of the salt in cold water we determined by precipi- 

 tating the saturated solution with sulphuric acid. 



I. 36.2176 grm. of a solution saturated at 20° gave 0.0197 grm. 

 BaSO,. 

 II. 32.6167 grm. of a solution saturated at 20° gave 0.0181 grm. 

 BaSO^. 



The aqueous solution saturated at 20°, therefore, contained the 

 following percentages of the anhydrous salt : — 



I. II. 



0.19 0.20 



Calcic Tribrompyromiicate, Ca(C.Br30g)2. 4H2O. — The calcium 

 salt we prepared by precipitating an ammoniacal solution of the acid 

 with calcic chloride. When recrystallized from hot water, it formed 

 clusters of fine dendritic needles, which were permanent in the air. 

 but effloresced over sulphuric acid. 



I. 1.5,009 grm. of the salt lost at 120° 0.1385 grm. H.p. 

 II. 0.9115 grm. of the salt lost at 120° 0.0799 grm. H,,0. 



Calculated for Found. 



Ca(C(iBr303^j.4Uo0. I. II. 



H,0 8.91 8.93 8.77 



I. 0.5885 grm. of the anhydrous salt gave on ignition with II.^SO^ 

 0.1060 grm. CaSO^. 

 II. 0.6364 grm. of the anhydrous salt gave on ignition with H,,SO^ 

 0.1122 grm. CaSO,. 



Ca 



In order to determine the solubility of the salt in cold water, we 

 precipitated the saturated solution with animonic oxalate, and con- 

 verted the calcic oxalate thus obtained into calcic sulphate by ignition 

 with sulphuric acid. 



VOL. XXI. (N. S. XIII.) 12 



