URINE. 183 



carbon disulphide, which, if iodine be pre- 

 sent, will be coloured pink. 

 For acetic, benzoic and kryptophanic acid, and 

 for urochrome and its products, see sepa- 

 rate articles. 



Examination of the Sediment. Allow any sediment 

 to deposit at the bottom of a conical glass. 

 Pour off as much of the liquid as possible, 

 then take up a little sediment with a pipette, place 

 on a glass slide, and examine with the micro- 

 scope. 



A. The urine is acid. 



I. The whole of the sediment seems amorphous. 



1. On gently warming the whole dissolves: 

 urates ; confirm by adding a drop of hydro- 

 chloric acid ; leave half an hour, when, if uric 

 acid be present, it will have crystallised out 

 in rhombic tables. 



Also confirm by the murexide test. 



2. The sediment does not dissolve on warming, 

 but dissolves in a drop of acetic acid without 

 effervescence ; presence of calcium phosphate. 



3. Glistening drops appear in the sediment and 

 disappear on the addition of ether : fat 

 globules. 



II. The sediment contains well-formed crystals. 



1. Small, glistening, transparent octohedra, 

 insoluble in acetic acid : calcium oxalate. 



