WHAT WE BREATHE 51 



clusively that the dirtier or more slumlike the 

 surroundings, the greater was the frequency with 

 which she found bacteria associated with disease 

 in the air. 



Messrs. Valenti and Terrari-Lelli have quite 

 recently been able fully to endorse these state- 

 ments in the results they have obtained in their 

 systematic study of the bacterial contents of the 

 air in the city of Modena. In their report they 

 state that the narrower and more crowded the 

 streets, the greater was the number of bacteria 

 present in the air, and the more frequently did 

 they meet with varieties associated with septic 

 disease. 



Numerous detailed investigations have also been 

 made of the bacterial contents of the dust in 

 hospitals. That cases of infection arising within 

 hospital precincts are of no uncommon occurrence 

 may be gathered from the observations made by 

 Lutand and Hogg, who report no fewer than 

 2,294 such cases having arisen in the space of 

 six years in certain Paris hospitals, whilst Solow- 

 jew records 1,880 cases as occurring in the space 

 of four and a half months in the St. Petersburg 

 city hospital. Solowjew made a special study of 

 the bacterial contents of dust collected in hos- 

 pitals, and states that 41-8 per cent, of the 

 samples examined contained disease germs. The 



