PEDAGOGICS OF BACTERIOLOGY 11 



tivities of the bacteria. After he has become familiar with 

 bacteriological technique and the methods of studying indi- 

 vidual cultures, he should be given pure cultures of the com- 

 mon types of bacteria. It is desirable that he should be able 

 to recognize all the ordinary bacteria that may be encountered 

 later in his work as contaminations so as to be able to avoid 

 confusing them with other bacteria that may be of importance 

 in the study that he is conducting. With the foregoing exercises 

 as a foundation the student is prepared to take up the study of 

 the bacteria in water, soil, air, milk, butter, cheese; in the differ- 

 ent orifices of the body; and in the excretions from the body. 

 In these studies it will be possible to observe merely a few of the 

 more common bacteria encountered, but each phase of the sub- 

 ject can be amplified by lectures, assigned readings, and dis- 

 cussions in the seminar. In the foregoing studies special exer- 

 cises may be arranged to enable the student to comprehend 

 the relation of bacteria to decomposition, putrefaction, fer- 

 mentation, nitrification, denitrification and nitrogen fixation, or 

 these phenomena may be independently attacked after the more 

 common bacterial flora in nature have been studied. If the latter 

 course is pursued the relation of the bacteria to these processes 

 should be taken up briefly as phases of the phenomena present 

 themselves, while the detailed study of the phenomena is carried 

 out later. 



A general course in bacteriology is not complete unless the 

 student is given at least a brief introduction to the relation of 

 bacteria to the diseases of plants and animals. This study 

 should include the methods of recognizing the causative agents 

 of disease, the manner in which they produce disease, and the 

 ways in which recovery from infection occurs. The student 

 should also have an introduction to the bacteriological side of 

 important problems in preventive medicine, especially the 

 eflSciency of disinfection by the use of chemicals, heat and fight. 

 The relation of bacteria to the purification of water and sewage, 

 and to the preservation of milk, eggs, meat and vegetables should 

 be developed by lectures, assigned readings and exercises in the 

 laboratory. 



