ALLOXANTIN. 1007 



sulphurous acid to form sulphuric acid, while the elements of 

 urile, ammonia and water combine and give rise to uramile. 



Uramile, C 8 N 3 H 5 O 6 , is prepared by adding hydrochloric acid 

 to a saturated and boiling solution of thionurate of ammonia, 

 till it is strongly acid; the heat is continued till the liquid 

 begins to become turbid ; it is then allowed to cool for crystal- 

 lization. Uramile crystallizes in thin and hard tufts, or presents 

 itself in the form of a brilliant white powder, composed of very 

 thin silky needles. It is sparingly soluble in hot water, wholly 

 insoluble in cold water, dissolves in ammonia and caustic alka- 

 lies, and is again precipitated, without alteration, by acids. 

 A solution of potash and dilute acids boiled upon uramile, con- 

 vert it into uramilic acid, disengaging ammonia. The am- 

 moniacal solution of uramile becomes purple-red in air, and 

 deposits crystalline needles of a green colour and metallic lustre. 

 In contact with oxide of mercury or oxide of silver, it is decom- 

 posed, by ebullition, into murexide, and at the same time 

 reduces the oxides to the metallic state. 



Uramilic acid, C 16 N 5 H 10 O 15 , is prepared by dissolving thionu- 

 rate of ammonia in cold water, adding to the saturated solution 

 a small quantity of sulphuric acid, and evaporating by a water- 

 bath; after a time uramilic acid is deposited in transparent, 

 four-sided prisms of a vitreous lustre, or in silky needles. It 

 is soluble in 6' or 8 parts of cold water, and in 3 parts of boiling 

 water ; the solution is feebly acid. In the formation of uramilic 

 acid 2 atoms of uramile unite with the elements of 3 atoms of 

 water, yielding up at the same time the elements of 1 atom of 

 ammonia. 



ALLOXANTIN. 



Formula: C 8 N 2 H 5 O 10 . Alloxantin was first observed by 

 Dr. Prout among the products of the decomposition of uric acid 

 by nitric acid, and more lately produced and studied by MM. 

 Liebig and Woehler. Several processes are given by the latter 

 chemists for its preparation. 1. From uric acid. One part of 

 uric acid is boiled with 32 parts of water, and dilute nitric acid 

 added by small portions at a time till the uric acid is completely 

 dissolved, and the liquor evaporated to two-thirds. In the 

 course of a few days, or sometimes a few hours, the alloxantin 



