URIC ACID. 159 



Heal acid ... 9 



Water 2-25 



11-25 



As 2-5 represents 2 atoms of water, the proba- 

 ble inference from this experiment is, that the 

 atomic weight of uric acid is 9, and that the 

 crystals constitute a hydrate composed of 



2 atoms water . . 2-25 



1 atom uric acid . . 9 



11-25 



4. 18 grains of crystallized carbonate of soda Analysis of 

 were dissolved in distilled water, and to the so- 

 lution 11 '25 grains of crystallized uric acid were 

 added. This mixture being digested for some 

 hours on the sand bath, the whole uric acid dis- 

 appeared, and a complete colourless solution was 

 obtained ; which, however, still rendered cud- 

 bear paper violet. The solution being set aside, 

 a bulky and beautifully white precipitate of urate 

 of soda fell : this precipitate being separated on 

 a double filter, well washed and dried in the 

 open air, was found to weigh 8*56 grains ; and, 

 when exposed to a heat of between 300 and 

 400, it lost very nearly 1'125 grains, the resi- 

 dual liquid was supersaturated with muriatic acid 

 and evaporated to dryness the residual matter, 

 which was white, with a shade of brown, weighed 

 6'94 grains. It was heated to redness, lixiviated 



