170 ESSENTIALS OF CHEMICAL PHYSIOLOGY 



the urine without the presence of any blood corpuscles at all. This 

 is produced by a disintegration of the corpuscles occurring in the 

 circulation. The condition so produced is called h&moglobinwria, 

 and it occurs in several pathological states, as, for instance, in the 

 tropical disease known as ' Black-water fever.' The pigment is in 

 the condition of methaemoglobin mixed with more or less oxyhaemo- 

 globin, and the spectroscope is the means used for identifying these 

 substances (see p. 119). 



PUS IN THE URINE 



Pus occurs in the urine as the result of suppuration in any part 

 of the urinary tract. It forms a white sediment resembling that of 

 phosphates, and, indeed, is always mixed with phosphates. The pus 

 corpuscles may. however, be seen with the microscope ; their nuclei 

 are rendered evident by treatment with 1-per-cent. acetic acid, and 

 the pus corpuscles are seen to resemble white blood corpuscles, 

 which, in fact, they are in origin. Some of the protein constituents 

 of the pus cells and the same is true for blood pass into solution, 

 so that the urine pipetted off from the surface of the deposit gives 

 the tests for albumin. On the addition of liquor potassae to the 

 deposit of pus cells a ropy gelatinous mass is obtained. This is 

 distinctive. Mucus treated in the same way is dissolved. 



