SUPPLEMENTAL PROGRAM ARRANGED FOR 



CLASS STUDY ON 

 HOUSEHOLD BACTERIOLOGY 



By S. Maria Elliott, Simmons College, Boston 



MEETING I 



(Study pages 1-14) 

 Dust and Dust Gardens 



The growth of a dust garden will impress this whole sub- 

 ject much more vividly than any amount of reading. Each 

 member should plant and watch the growth of at least one 

 garden. One person might prepare and sterilize the nutrient 

 gelatine for the class, distributing in sterilized wide-mouth 

 vials or test tubes about two teaspoonfuls to each. Each 

 member should sterilize the dish or dishes, melt the gelatine 

 by placing the tube in cold water and then heating it, pour 

 into the Petri dish, cover, cool, and plant. 



(If not to be had locally, a dozen Petri dishes may be 

 obtained through the School for $1.90, a half a dozen for 

 $ i . oo, not including express charges. Money will be refunded 

 for those returned. ) 



Arrange as varied conditions for experiment as possible. 

 The following list is only suggestive of interesting sources 

 and methods of treatment: 



(a) After sweeping a carpeted room with a dry broom, 



expose five minutes, keep at room temperature, but 

 not in direct sunlight. 



(b) Same as above but kept in a refrigerator. 



(c) Same as "a" but shut up in a box. 



(d) Dig out from some corner of stairway or room the dirt 



which was overlooked in cleaning. Pulverize this 

 and scatter a little over the jelly. Keep in any 

 condition desired. 



(e) Let a fly walk over the media. 



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