180 PROCEEDINGS OF THE AMERICAN ACADEMY 



needles which melted at 222-223°. It was readily soluble iu hot 

 alcohol, quite sparingly soluble in ether, chloroform, or benzol, iusoiu- 

 ble in carbonic disulphide or ligroin. It was nearly insoluble even in 

 boiling water. 



0.6792 grm. substance gave 23.5 c.c. of moist nitrogen at 22° and 

 under a pressure of 744 mm. 



Calculated for CgBrjOjNHj. Found. 



N 4.02 3.92 



Action of Bromine and Water. 



Bromine acts but slowly upon tribrompyromucic acid suspended in 

 water, and even if the acid be finely subdivided a portion of it escapes 

 decomposition. Since little action was visible when the vapor of 

 bromine was slowly led in by means of a current of air, we added 

 exactly one molecule of bromine, and then collected upon a filter the 

 insoluble matter which remained. A portion of this dissolved in a 

 dilute solution of sodic carbonate, and could be reprecipitated by the 

 addition of hydrochloric acid. The properties of the precipitated acid 

 and its melting-point (216°) showed it to be unaltered tribrompyro- 

 mucic acid. The portion which was insoluble in the alkaline solution 

 was dissolved in boiling alcohol, and on cooling crystallized in long 

 slender needles which melted at 63-64°, An analysis gave the per- 

 centage of bromine required by tetrabromfurfuran. 



0.2217 grm. substance gave 0.4359 grm. AgBr. 



Calculated for C4Br40. Found. 



Br 83.33 83.68 



The aqueous solution filtered from the tetrabromfurfuran and the 

 unaltered tribrompyromucic acid yielded, on extraction with ether, 

 dibrommaleic acid in quantity too small to admit of analysis, although 

 its identity could readily be established by the melting-point of its 

 anhydride (114-115°). With aqueous bromine, therefore, tribrom- 

 pyromucic acid yields essentially tetrabromfurfuran and carbonic di- 

 oxide according to the equation, 



C^HBrgO^ + Br^ = C,Br,0 + CO, 4- HBr. 



Action of Nitric Acid. 



Tribrompyromucic acid is much less readily attacked by dilute nitric 

 acid than either of the dibrompyromucic acids, and to effect its oxida- 



