OF ARTS AND SCIENCES. 2G1 



theoretically required, and the solution boiled. The .-alt separated 

 as the solution cooled, and was purified by recrystallization from hot 

 water. It was filtered rapidly and dried in vacuo over sulphuric acid 

 and potassic hydrate. The salt is quite soluble in hot, but slightly 

 soluble in cold water. When cooled rapidly, it forms a jelly-like 

 mass ; but when cooled slowly, it crystallizes in flat, transparent 

 prisms. 



0.2177 gr. salt dried in vacuo gave 0.0307 gr. H,0 = 14.10% 

 Calculated for BaC 5 (CH 8 ) s N 4 8 . 3 H 2 . ." . 14.03% 



0.1875 gr. anhydrous sail gave 0.1335 gr. BaS0 4 . Ba = 41.80% 

 Calculated for BaC 6 (CH 8 ) 2 N 4 8 41.89% 



Monobaric dimetliylurate. 

 Ba(C 3 H(CH 3 ) 2 N 4 O a ) 2 .3H 2 0. 



This salt was made by boiling an aqueous solution of the acid with 

 baric carbonate, filtering, and precipitating the filtrate with alcohol. 



0.3GG1 gr. salt dried in vacuo gave 0.0342 gr. H.,0 = 9.34% 

 Calculated for Ba (C 5 H(CH 3 ) 2 N 4 3 ) 2 . 3 H.,0. " . 9.29% 



0.3350 gr. anhydrous salt gave 0.1491 gr. BaS0 4 . Ba = 20.17% 

 Calculated for Ba (C 6 H(CH 3 ) 2 N 4 3 ) 2 .... 25.99% 



Further study of the salts of dimethyluric acid seemed to us of no 

 immediate importance, since the results we had reached served to 

 establish beyond all doubt its dibasic character. 



Action of HydrocJdoric Acid. 



Dimethyluric acid, when heated with concentrated hydrochloric 

 acid, is completely decomposed, giving products perfectly analogous to 

 those described by Strecker* as resulting from the decomposition of 

 uric acid, and qualitatively identical with those obtained under the 

 same conditions from methyluric acid. 



The dimethyluric acid was heated for several hours with hydro- 

 chloric acid saturated at 0° to 170°. The liquid from the tubes, which 

 showed great pressure on opening, was evaporated to dryness on the 

 water-bath, the residue dissolved in water and distilled with plumbic 

 hydrate in a current of steam as long as the distillate gave an alka- 

 line reaction. The distillate was caught in hydrochloric acid, evap- 



* Ann. Chem. u. Pharm., exlvi. 142; Zeitachr. fur Chemie, 18G8, p. 215. 



