228 INFECTIOUS AND PARASITIC DISEASES. 



in pulmonary tuberculosis, when the sputum-cup has 

 stood awhile, the contents are seen to consist of an upper 

 watery layer, and a lower tenacious mass which, when 

 shaken, is seen to be made up of round, coin-like partic- 

 les. This is the so-called mummular sputum which is 

 characteristic of the second and third stages of consump- 

 tion. 



Worth remembering also is the fact that on standing 

 twenty-four hours or longer in a warm room, a tenacious 

 sputum may become liquefied through solution of its 

 mucus by ferments. 



Much valuable information may be derived 

 Color. from the color of a sputum. Sputum may 



vary from the clear glairy appearance of 

 normal saliva, to grey, yellow, green, red, brown, and 

 even black. A greenish or yellow color indicates either 

 pus (purulent), or bile (bilious); a red color, blood (san- 

 guineous); a brown or chocolate color, liver abscess; 

 and black, carbon, a condition resulting from the inhala- 

 tion of carbon particles as is practised by smokers for 

 pleasure or by miners from necessity. 



If there is anything unusual to the odor of a 

 Odor. sputum, it should be noted. Most sputa 



are practically odorless. However, under 

 certain circumstances, e.g., putrid bronchitis, the other 

 extreme is presented, and the offensiveness of the 

 expectoration beggars description. In pulmonary tu- 

 berculosis the sputum has a sweetish odor. 



