112 THE STORY OF THE BACTERIA. 



atically and the larger particles of dirt collected 

 and removed ; but the floating dust is simply 

 stirred up, and after settling is stirred up again 

 by the so called duster, and so partially 

 removed from the seats, but it settles again 

 on the floors, to be again set in motion by the 

 entering and retiring audience. It would be 

 safe to say that the only systematic mode of 

 removal of the floating dust from many of our 

 popular theatres and churches is by its lodg- 

 ment in the throats and lungs or on the 

 clothing of the people who visit them. 



Some of the newer theatres are furnished 

 with improved and sufficient ventilating appa- 

 ratus, but some of them are not, and while we 

 admire the chaste gilding and sumptuous up- 

 holstery of the interior, and complacently 

 reflect that at length the law has forced 

 builders of places of amusement to afford a 

 measurable degree of security against being 

 burned alive, that element of danger in large 

 assemblies, more important and more subtle 

 than all the rest put together, namely, inade- 

 quate ventilation, is rarely commented upon or 

 thought about. There ought to be definite 



