56 CLINICAL BACTERIOLOGY AND HEMATOLOGY 



When this process is successful, the spores are stained red, and 

 the bacilli blue (Plate I., Fig. 4). 



The presence of spores enables us to isolate the bacilli from most 

 of the organisms with which they are likely to be contaminated, 

 by a very simple process. The spores resist the action of heat 

 just as they resist stains, and for the same reason, and a suitable 

 temperature will kill off all the non-sporing organisms and spare 

 the spores. The latter may then be inoculated at a suitable 

 temperature, and will develop into bacilli. This process, however, 

 is not applicable to the examination of the blood or morbid 

 effusions, as the bacillus of anthrax does not form spores in the 

 living body. In this it differs from the tetanus bacillus, in which 

 the process may be applied direct to the material from the body. 



Investigation of a Supposed Case of Malignant Pustule. 



Requisites. — i. Several glass pipettes ; if cultures are not 

 required, one will be enough. 



2. Clean slides and cover-glasses. 



3. Bunsen burner or spirit-lamp. 



4. LofHer's methylene blue ; also the materials for Gram's 

 staining. 



5. Balsam. 



6. Tubes of gelatin if cultivations have to be taken. 



Method. — Break off the extreme tip of one of the glass pipettes 

 and insert into one of the vesicles around the dark papule in the 

 centre of the lesion ; it may be necessary to make a puncture 

 with a sterilized needle before this can be done. If the fluid does 

 not rise spontaneously into the pipette, break off the other end 

 and suck gently, watching the column of fluid so that it does not 

 get into your mouth. It is safer to use a pipette with a wide 

 mouthpiece plunged with cotton- wool (Fig. 14), or, best of all, 

 to suck up the fluid by means of an india-rubber nipple. 



Having obtained a drop or two of the fluid exudate, blow it out 

 on to the surface of a clean slide and spread it out into a film ; 

 prepare as many of these as you can. Allow them to dry, and 

 stain one with Lofiler's blue and some by Gram's method. 



Examine with the oil-immersion lens. Make a careful search 

 over the films, looking for large cigarette-shaped bacilli, noting 

 whether they are or are not arranged in chains. Examine the 

 Gram specimens, and see whether the bacilli are to be seen in 

 them also. 



