L'14 A Manual of Veterinary Physiology. 



Mucus in large quantities is a normal constituent of 

 horse's urine, but under disease the amount may be so 

 increased as to render the urine more like linseed-oil. This 

 might be taken for albumin. To distinguish it as mucin, 

 it presents none of the albumin reactions mentioned, and is 

 not affected by boiling. Acetic acid gives a precipitate 

 or cloudiness with mucin, Insoluble in exci 88. 



Pus is rarely present in urine, due to the fact that sup- 

 purative disease of the kidneys or bladder in animals is 

 certainly uncommon. Pus is distinguished by its micro- 

 scopical appearance ; the urine likewise gives an albuminous 

 reaction. 



Blood. — The only reliable clinical test is the microscope. 

 The presence of blood can with certainty be determined 

 by the spectroscope. The coffee-coloured urine of azoturia 

 is due to methremoglobin. 



Carbolic Acid is found in the urine of horses combined 

 with sulphuric acid. It can readily be detected by dis- 

 tilling urine with sulphuric acid ; the distillate smells 

 strongly of the acid. It is a normal constituent, but is 

 said to be absent in bowel affections, though this does not 

 accord with my experience, so far as I have had an oppor- 

 tunity of observing. 



A rough but useful clinical examination of the urine may 

 be made in the following way : 



Take the Reaction of the fluid with test-paper; it is 

 always markedly alkaline in health, and almost invariably 

 acid in inflammatory diseases. 



The Specific Gravity may be taken by an ordinary urino- 

 meter, using it at the temperature at which the instrument 

 is graduated, generally (iO Fahr. 



The Colour is judged of by transmitted light, some filtered 

 urine being placed for this purpose in a test-tube and held 

 up to the light. Occasionally the urine gives one colour by 

 reflected, and another by transmitted Light ; the reflected 

 light is often blue. This is generally, perhaps always, 

 found in stale urine or urine 24 hours old. 1 have never 

 seen it in the perfectly fresh fluid ; it, is due to indigo blue. 



