XXIII.] URINE. 241 



in a tall glass jar. Brownish red crystals of uric 

 acid will form at the sides and hottom of the 

 jar. Examine one or two of these under the 

 microscope, to the rest apply the murexide test 

 (§ 7. c). 



Tests for some Abnormal Constituents of the 

 Urine. 



9. Albumin. 



a. Boil, making the fluid just acid with acetic 

 acid; albumin if present is coagulated (cp. 

 Lesson iii. § 17). 



b. Apply also the tests for proteids. 



10. Sugar. Coagulate any albumin that may be 

 present (cp. § 9) and filter; apply Trommer's 

 test' (Lesson xv. D § 7). 



The colouring matter of the urine may be re- 

 moved by pouring it on a filter containing some 

 animal charcoal moistened with water; it must 

 be remembered however that if the quantity of 

 sugar present is small it may be retained by the 

 charcoal. 



11. Bile Figment. Use Gmelin's test (Lesson 

 XVII. B, § 3). 



' If a faint reaction only is obtained, it cannot be relied on as 

 shewing the presence of sugar, since several other bodies (e.g. urie 

 acid) which occur in urine also reduce oupric oxide. 



L. 16 



