no BACTERIA 



ment of the disease. Delalivesse, examining the air of wards 

 at Lille, found that the contained bacteria varied more or 

 less directly with the amount of floating matter, and de- 

 pended also upon the vibration set up by persons passing 

 through the ward and the heavy traffic in granite-paved 

 streets adjoining. Bacillus colij staphylococci, and strepto- 

 cocci, as well as B. tuberculosis yV^^r^ isolated by this observer. 

 Some new Hght has been thrown upon the subject of 

 pathogenic organisms in air by Neisser in his investigations 

 concerning the amount and rate of air-currents necessary to 

 convey certain species through the atmosphere. He states 

 that the bacteria causing diphtheria, typhoid fever, plague, 

 cholera, and pneumonia, and possibly the common Strepto- 

 coccus pyogenes, are incapable of being carried by the mol- 

 ecules of atmospheric dust which the ordinary insensible 

 currents of air can support, whilst Bacillus anthracis, B. 

 pyocyaneus, and the bacillus of tubercle are capable of being 

 aerially conveyed^ This work will require further confirm- 

 ation, but if its truth be established, it proves that attempted 

 aerial disinfection of the first group of diseases is useless. 



