166 PROCEEDINGS OF THE AMERICAN ACADEMY 



prepared was very readily soluble in alcohol, ether, chloroform, car- 

 bonic disulphide, or benzol, more sparingly soluble in ligroin, from 

 which it crystallized in long lustrous prisms which melted at 55-56°. 

 By the slow evaporatiou of the solution in ligroin quite large and 

 well-developed individuals could be obtained. The substance dried 

 over sulphuric acid gave on analysis the following results : — 



I. 0.9G63 grm. substance gave 0.5285 grm, CO2 and 0.0300 grm. 

 H,0. 

 II. 0.2053 grm. substance gave 0.3594 grm. AgBr. 

 III. 0.2344 grm. substance gave 0.4109 grm. AgBr. 



Found. 

 II. HL 



74.50 74.61 



When boiled with water this substance was gradually decomposed, 

 and the aqueous solution then appeared to contain a mixture of di- 

 bromsuccinic, monobromfumaric, and monobrommaleic acid, as far as 

 could be determined from the melting-points and other physical prop- 

 erties of the products obtained by evaporation and recrystallization. 

 Since we thought it not improbable that the dibromsuccinic and mono- 

 bromfumaric acids had been formed from the monobrommaleic acid by 

 the action of the hydrobromic acid formed in the reaction, we decora- 

 posed the substance by heating it with a dilute solution of potassic 

 hydrate, added hydrochloric acid in quantity just sufficient to set the 

 organic acid free, extracted with ether, and recrystallized from water 

 the residue left upon evaporation of the ether. In this way we ob- 

 tained a homogeneous product which melted at 126-127°, and which 

 gave on analysis the percentage of bromine required by monobrom- 

 maleic acid. 



0.2099 grm. substance gave 0.2013 grm. AgBr. 



Calculated for CiIIaBrOi. Found. 



Br 41.03 40.82 



The chief product of the action of aqueous bromine upon ^^-dibrora- 

 pyromucic acid was therefore monobrommaleyl bromide formed accord- 

 ing to the equation, 



C^HjBrPa + 2 Br, + H,0 == CJiBr.O, + CO, + 3 II Br. 



