434 MORBID PRODUCTS. 



if, after the solution has been neutralized by ammonia, oxalate 

 of ammonia throws down a precipitate. 



If the specimen is not affected by acetic acid, but dissolves 

 readily in nitric or hydrochloric acid without effervescence, and 

 is precipitated therefrom by ammonia; and if, farther, the 

 nitric-acid solution evaporated nearly to dryness and treated 

 with ammonia develops no purple tint, it consists of oxalate of 

 lime. 



e. It is carbonate of lime if it easily burns white before the 

 blowpipe, and in other points resembles oxalate of lime after 

 exposure to a red heat ; if the fresh specimen dissolves with 

 effervescence in acetic or hydrochloric acid, and the solution is 

 not precipitated by ammonia ; and if oxalate of ammonia throws 

 down a precipitate from the ammoniacal solution. 



/. It is urate of soda (which never occurs alone in urinary 

 concretions, but is found, like the urate of potash, in small 

 quantity in calculi of uric acid and the earthy phosphates,) if 

 it fuses readily before the blowpipe, but burns white with dif- 

 ficulty, and communicates an intense yellow tint to the flame ; 

 if the residue (with the exception of particles of carbon) dis- 

 solves easily in water, to which it communicates an alka- 

 line reaction, and dissolves with effervescence in hydrochloric 

 acid, if the addition of bichloride of platinum to the filtered 

 solution mixed with alcohol, producing no deposit; and if afresh 

 specimen dissolves in water on the application of heat, dissolves 

 in nitric acid without effervescence, and the solution, after 

 evaporation nearly to dryness, assumes a purple tint on the 

 addition of ammonia. 



g. It is urate of potash if it behaves exactly like urate of 

 soda, (with the exception of communicating a yellow colour 

 to the flame of the blowpipe;) and if a yellow precipitate is 

 formed on the addition of bichloride of platinum to an alcoholic 

 solution of the ash dissolved in hydrochloric acid. If, in con- 

 junction with the occurrence of the yellow precipitate, the 

 specimen communicates an intense yellow colour to the flame 

 of the blowpipe, urate of soda is mixed with the urate of 

 potash. 



h. It is urate of lime (which never occurs alone, but is 

 usually associated with uric acid in calculi) if it burns white 



