OP ARTS AND SCIENCES. 139 



The S-monobrompyromucic aciil crystallizes from water in irregular 

 leafy plates with pearly lustre which melt at 183-184°. It is readily 

 soluble in alcoh.J or ether, si^aringly soluble in cold chloroform or 

 benzol, more freely soluble on heating. In carbonic disulphide or 

 ligroin it is almost insoluble. In cold water it is sparingly soluble, 

 but dissolves freely on heating. The solubility of the acid in water 

 at ordinary temperatures we determined according to the method of 

 V. Meyer. The acid solution was neutralized with baric carbonate 

 and the barium dissolved precipitated with sulphuric acid. 



I. 37.59G5 grm. of a solution saturated at 1G.5° gave 0.0500 grm. 

 BaSO,. 

 II. 3G.G804: grm. of a solution saturated at 16.5° gave 0.0488 grm. 

 BaSO,. 



The aqueous solution of the acid saturated at 16.5° therefore con- 

 tained the percentages : — 



I. II. 



0.22 0.22 



Baric h-Monobrompyromucate, Ba(C-H2Br03)2 . 4 H.,0. — By neu- 

 tralizing an aqueous solution of the acid with baric carbonate we ob- 

 tained the barium salt in the form of irregular pearly plates which were 

 readily soluble in hot water, more sparingly in cold. The air-dried 

 salt contained four molecules of water,* most of which it lost over 

 sulphuric acid. 



I. 1.2927 grm. of the salt lost at 105° 0.1 5G3 grm. IT.O. 

 II. 1.3857 grm. of the salt lost at 105° 0.1G76 nvm. 11,0. 



I. 0.3394 grm. of the anhydrous salt gave on ignition with II^SO^ 

 0.1527 grm. BaSO,. 

 II. 0.4088 grm. of the anhydrous salt gave on ignition with H^SO^ 

 0.1848 grm. BaSO,. 



Calculated for Found. 



Ba(C5lI.,Br03V I. II. 



Ba 26.50 26.44 26.57 



* Canzoneri and Oliver! assign to tliis salt the formula BafCjIIjBrOa)., . 2irL0. 

 Since tlieir analytical data agree with ours, their incorrect formula is evidently 

 due to an error in calculation. 



