46 



place. Observe it from day to day, noting its reaction, 

 change of color, transparency, odor and any deposits that 

 may form in it. 



225. Dip some neutral litmus paper into some normal 

 urine. It is turned red. Do the same with some stale 

 urine. It is turned blue. Warm the paper just used, the 

 blue may fade indicating the presence of a volatile alkali 

 (ammonium carbonate). The blue color does not disappear 

 with heating when a fixed alkali is pre.sent. 



226. Inorganic constituents of urine. The ratio of inor- 

 ganic to organic constituents is i to 1.2— 1.7. The amount 

 of salts excreted in twenty-four hours is 16 to 24 grama 

 (J^ to yi oz.). 



Samples of omnivorous, carnivorous, and herbivorous 

 urines are furnished. Apply the same tests to each at the 

 same time and note any differences as to color, specific 

 gravity, reaction and responsiveness to the various tests. In 

 all cases the urine must be filtered and thoroughly clear be- 

 fore attempting the tests. 



The herbivorous and carnivorous urines may be obtained 

 with the aid of a catheter, when the bladder is full. The 

 mare and the bitch are convenient animals for this purpose, 

 as it is easier to pass the catheter in the female than the male. 

 Human urine may be used as an example of the omnivorous- 

 excretion. 



227. The urinometer may be a few degrees out of the way. 

 Test it by filling the urinometer jar with distilled water at 

 15° C. (60° F. ). Read the division of the scale correspond- 

 ing with the surface of the fluid looking above or below the 

 meniscus as is found to be the mo.st correct for the zero read- 

 ing. Always adhere to this method when using the same 

 urinometer. Test the urines, making the necessary correc- 

 tions. If the urine is warmer than 15" C. add 1° to the 

 density for every 4° of extra C. temperature, or for every 7°^ 

 of extra F. temperature. 



