114 ANIMAL OXIDES WITH AZOTE NOT OILY. 



The urea is disengaged, and there remains the 

 acid, Cz 8 Az 2 O 4 



Add 2 atoms oxygen, . . O 2 



4 atoms water, . H 4 O 4 



we have C 8 H 4 Az 2 O 10 



which is an atom of alloxane. 



The urea, as is well known, and the nitrous acid formed mu- 

 tually, decompose each other into nitrite of ammonia, and free 

 cyanic acid. The nitrite of ammonia, by a gentle heat, is de- 

 composed into azotic gas and water ; while the cyanic acid, along 

 with the elements of water, is decomposed into ammonia and 

 carbonic acid. Equal volumes of these two gases ought to be 

 disengaged, while the proportion of ammonia formed by the de- 

 composition of the cyanic acid ought to remain in the liquid. 

 Now, as all this is what actually takes place, there can be no 

 doubt of the accuracy of the explanation of the action of nitric 

 acid on uric acid given by Wohler and Liebig. 



When crystals of anhydrous alloxane are dissolved in concen- 

 trated muratic acid by the assistance of heat, we perceive an ef- 

 fervescence which continues till the action is complete. The pro- 

 ducts differ according to the mode of proceeding. If we only 

 heat the solution for a few minutes it becomes muddy, and de- 

 posites on cooling a great number of brilliant and transparent 

 crystals of alloxantin. The solution being freed from these crys- 

 tals, and purified from muriatic acid by evaporation, gives crys- 

 tals of oxalate of ammonia. The decomposition consists in the 

 separation of two atoms of alloxane into oxalic acfd, oxaluric 

 acid, and alloxantin. 



1 atom oxalic acid, = C 2 O 3 



2 atoms alloxane 

 = C 16 H 8 Az 4 CP 



1 atom oxaluric acid, = O 6 H 3 Az 2 O 7 

 1 atom alloxantin, = C 8 H 5 Az 2 O 10 



C 16 H 8 Az 4 O 20 



The oxaluric acid, by boiling with muriatic acid, is decompos- 

 ed into cyanate of ammonia, the acid of which, in presence of the 

 same agent, becomes bicarbonate of ammonia. 



Alloxane treated in the same way with dilute sulphuric acid 

 gives the same products. This is a very convenient and rapid 

 way of obtaining alloxantin. 



By a long continued boiling, the alloxantin disappears in its 



