272 



A MANUAL OF BACTERIOLOGY 



The mean annual results (for eight years, 1881-88) 

 of the number of microbes contained in one cubic 

 metre of the air at Montsouris and in the vicinity 

 of the Hotel de Ville (i.e. in the centre of Paris) are 

 given in the following table : 



From the above results it will be seen (a) that 

 there are a larger number of microbes in the atmo- 

 sphere in the centre of Paris than at Montsouris ; 



