OF ARTS AND SCIENCES. 145 



The less soluble acid crystallized from hot water in well-defined 

 prisms, which remained unchanged when heated to 200°. An analysis 

 showed this acid to be ordinary dibromsuccinic acid. 



0,2468 grm. substance gave 0.3363 grm. AgBr. 



Calculated for C^HiBrjOi. Found. 



Br 57.97 57.98 



The aqueous solution from which the two dibromsuccinic acids had 

 been extracted with ether still contained a certain amount of fumaric 

 acid, which was obtained by evaijoration and identified by qualitative 

 tests. 



The substance insoluble in water which had been formed by the 

 action of bromine was recrystallized, first from alcohol, then from 

 ligroin, and crystallized in colorless prisms which melted at 110-111°. 

 Analysis showed the substance to be dibromfurfurantetrabromide. 



I. 0.7407 grm. substance gave 0.2380 grm. CO, and 0.0284 grm. 



H=0. 

 II. 0.2054 grm. substance gave 0.4259 grm. AgBr. 

 III. 0.1680 grm. substance gave 0.3476 grm. AgBr. 



m. 



88.04 



This substance will be more fully studied and the results presented 

 to the Academy at a future time. The action of bromine upon the 

 8-monobrompyromucic acid under the conditions we have chosen may 

 therefore be expressed by the following equations : — 



C,H3Br03 + 2 Br, + 3 H.fi = C^H^, + CO, + 5 IIBr. 

 C.HgBrOg + 3 Br, + 3 II^O = CJI,Br.,0, + COj + 5 HBr. 

 C5H3Br03 + 3 Br, = C,H,Br,0 + CO,' + HBr. 



Action of Nitric Acid. 



On warming S-monobrompyromucic acid with dilute nitric acid it is 

 readily oxidized, carbonic dioxide is given off in abundance, and a small 

 quantity of a yellowish oil distils over, which has not yet been further 

 examined. For the complete oxidation of the acid we have found it 

 best to take an equal weight of nitric acid (sp. gr. 1.42), diluted with 

 four times its weight of water. The solution on cooling deposits crys- 

 VOL. XXI. (n. 8. xm.) 10 



