OF ARTS AND SCIENCES. 



139 



According to these determinations the aqueous sohition of the acid 

 saturated at 18° contained the percentages : — 



I. 

 5.32 



II. 

 4.95 



Baltic Dibromacrylate, ^^{C^l^v.f).^.,. ir>0. By neutralizing the 

 arid with baric carbonate, or more conveniently by the direct evapo- 

 ration of the solution obtained by the action of baric hydrate upon 

 tribrompropionic acid, we obtained the barium salt in leafy rhombic 

 plates which, when dried over sulphuric acid, contained one molecule 

 of water. 



I. 1.1489 grra. of the salt dried over II.^SO^ lost at 100-105° 0.0335 

 grm. H,0. 

 II. 1.5158 grra. of the salt dried over H.,SO^ lost at 105-110° 0.0457 

 grm. H._,0, and gave on precipitation 0.5790 grm. BaSO^ . 



Calculated for Ba(C3HBr.20.J., . H.O , 



Found. 



Ba 

 H,0 



22.35 

 2.94 



Calcic Dihromacrylate, Ca(C3HBr20„).2 . 3 HgO. The calcium salt 

 crystallized in radiating needles which contained when air-dried three 

 molecules of water. 



0.9444 grm. of the air-dried salt lost at 100-105° 0.0906 grm. Hp, 

 and gave on ignition with HgSO^ 0.2332 grm. CaSO^ . 



Calculated for Ca ( CgHBroO J o. 3 H.p . Found. 



Ca 7.25 7.26 



H^O 9.78 9.59 



These results are sufficient to prove that this dibroraacrylic acid is 

 identical with the one already studied, as a comparison of the mean 

 results given in the followino; table will show. 



