14 BACTERIOLOGY 



faction, and used for experiments on animals. In order to 

 procure pure cultures, however, the instruments and 

 utensils employed must be freed from the micro-organisms 

 adhering to them, or sterilised. It seems, therefore, 

 advisable first to discuss the methods of sterilisation, and 

 then the preparation of culture-media, passing on after- 

 wards to microscopic examination, and, finally, the methods 

 of transmission to living animals. 



