URIC ACID. 157 



being thrown down. When I allowed the pre- 

 cipitated acid to remain in the mother liquor for 

 ~ 1 hours, I never got it in any other state than 

 an impalpable powder. 



Uric acid is tasteless, very white, very light, 

 and quite insoluble in water and alcohol. 



In concentrated sulphuric acid it speedily as- 

 sumes the form of a jelly ; and, upon applying a 

 very gentle heat, a complete solution is obtained, 

 without in the least affecting the colour or trans- 

 parency of the acid. In nitric acid, even though 

 dilute, it dissolves with effervescence. The so- 

 lution is nearly colourless, and when it is evapo- 

 rated to dryness, it leaves a sediment having a 

 beautiful pink colour ; and if water be poured 

 over it, a most lovely pink coloured solution is 

 obtained which, however, cannot be preserved 

 for any length of time without entirely losing its 

 colour. In muriatic acid it dissolves only in 

 small proportion, the undissolved part assuming 

 a fine white colour. If uric acid be precipitated 

 with a tinge of buffer yellow, which sometimes 

 happens, the easiest way of restoring the white- 

 ness is to digest it in pure muriatic acid. When 

 the muriatic acid is evaporated, it leaves a slight 

 sediment upon the bottom of the vessel, which 

 has a yellowish brown colour, and which is not 

 altered by pouring water over it. 



2. Uric acid may be united with the different 

 bases by boiling it in water, holding the wished- 



