BACTERIOLOGY. 189 



in the respiratory organs. They are always mixed 

 with other organisms. The purest cultures can be se- 

 cured from the greenish yellow-pus that may be col- 

 lected from the person so affected. As the disease 

 advances, we may be able to find the germs in the 

 leucocytes of the blood. It is a peculiar fact that the 

 bacilli remain in the sputum for a while after the dis- 

 ease is cured. 



Method of Making the Examination. Take some 

 of the greenish yellow pus and make the usual cover- 

 glass preparation, and stain the same with carbol- 

 fuchsin. 



Give the use of the agglutinating test of Widal. 



What is the thermal death-point of bacillus typho- 

 sus? 



Watch the demonstrator use the anaerobic culture 

 tube. 



Widal's Test is as follows: Take one drop of the 

 blood of the patient and mix it with nine drops of 

 water; place one of these drops on a cover-glass; 

 make ready a hanging-drop slide; now transfer one 

 drop of a culture of bacillus typhosus and examine 

 at once. If an agglutination occurs within fifteen 

 minutes the patient has typhoid fever. 



Make a spread of bacillus anthracis and examine 

 it, using the oil lens. Study spore- formation from this 

 bacillus. 



