OF ARTS AND SCIENCES. 287 



Baric fi -Chlordibromacrylate, Ba(C3ClB^02)2 • 3 IIoO. — A solution 

 of the acid was heated with an excess of baric carbonate, filtered, and 

 concentrated by evaporation. On cooling, the barium salt crystallized 

 in oblique slender prisms, which were somewhat more soluble in cold 

 water than the barium salt of the a-acid. After drying to a constant 

 weight in the air the salt contained three molecules of crystal water, 

 which were slowly given up over sulphuric acid, but more rapidly at 

 80°. 



I. 0.7765 grm. of the air-dried salt lost 0.0565 grm. H2O at 80°. 



II. 1.0502 grm. of the air-dried salt lost 0.0782 grm. 11,0 at 80°. 



III. 0.7185 grm. of the anhydrous salt gave 0.2462 grm. BaSO^. 



IV. 0.5975 grm. of the anhydrous salt gave 0.2051 grm. BaSO^. 



Calculated for Found. 



BalCjClBroOolo.SHjO. I. II. 



ll.f) ii-2 7.27 7.45, 



Calculated for 

 BaCCsClBrjOolj. III. IV. 



Ba 20.63 20.15 20.18 



In determining the solubility of the barium salt in cold water the 

 following results were obtained : — 



I. 1.5511 grm. of a solution saturated at 20° gave 0.1413 grm 



BaSO,. 



II. 1.8345 grm. of a solution saturated at 20° gave 0.1676 grm. 



BaSO,. 



The solubility of the salt in water at 20° is therefore shown by the 

 following percentages : — 



I. II. 



25.90 26.04 



Calcic (i-CIilordibromacrylate, Ca(C3ClBr.,02)2 • '^ H>0. — On con- 

 centi-ating a solution of the calcium salt prepared by neutralizing a 

 solution of the acid with calcic carbonate, the sak separated in clusters 

 of branching needles, which were less soluble in water than the calcium 

 salt of the a-acid. 



I. 1.2644 grm. of the air-dried salt lost 0.1345 grm. H,0 at 80°. 



II. 0.9273 grm. of the air-dried salt lost 0.1038 grm. 11,0 at 80°. 



III. 1.2124 grm. of the air-dried salt lost 0.1328 grm. H.O at 80°. 



IV. 0.8820 grm. of the anhydrous salt gave 0.1887 grm.'CaSO^. 



