THE STORY OF THE BACTERIA. 113 



regulations for all public assembly-rooms, 

 which should insure the forcing of a proper 

 amount of fresh air through them, which would 

 not only carry off foul air, but much of the 

 floating and possibly infectious dust with it. 



In dwelling-houses, the problem of ventila- 

 tion is in many respects simpler than in large 

 assembly-rooms, because to a certain extent the 

 householder is aware of the possibilities of 

 dust infection, from the condition of health of 

 the inmates, and can act accordingly. But 

 even here, under ordinary conditions, there 

 seems to be, from what we have learned about 

 the bacteria, more reasons than we have 

 before appreciated for securing adequate ven- 

 tilation such ventilation as shall carry off not 

 only the used-up air but the floating dust. 



The ordinary practice of occasionally stirring 

 up the settled dust with a feather-duster should 

 give place to the use of moist cloths or dry 

 cloths frequently shaken out-of-doors, so that 

 the dust may be removed and not simply 

 redistributed. This becomes the more impor- 

 tant if any inmate of the house is suffering 

 from one of the bacterial diseases. 



