188 BACTERIOLOGY. 



set about one or one and a half feet apart in the chamber. 

 A chamber having a capacity of 200 to 250 cubic feet 

 would thus afford accommodation for about one hundred 

 books at a time. 



Books, with the exception of their surfaces, cannot 

 be satisfactorily disinfected by formaldehyde gas in the 

 book-cases of houses and libraries, or anywhere except 

 in special chambers constructed for the purpose, because 

 the conditions required for their thorough disinfection 

 cannot otherwise be complied with. 



The bindings, illustrations, and print of books are in 

 no way affected by the action of formaldehyde gas. 



4. Disinfection of Carriages, Etc. 



Carriages, ambulances, cars, etc., can be easily disin- 

 fected by having built a small, tight building, in which 

 they are enclosed and surrounded with formaldehyde 

 gas. Such a building is used for disinfecting ambu- 

 lances in New York City. With the apparatus there 

 employed a large amount of formalin is rapidly vapor- 

 ized, and superficial disinfection is completed in thirty 

 minutes. 



5. Advantages of Formaldehyde Gas over Sulphur Dioxide 

 for the Disinfection of Dwellings. 



Formaldehyde gas is superior to sulphur dioxide as 

 a disinfectant for dwellings, first, because it is more 

 efficient in its action; second, because it is less inju- 

 rious in its effects on household goods; third, because 

 when necessary it can easily be supplied from a gen- 

 erator placed outside of the room and watched by an 

 attendant, thus avoiding in some cases danger of fire. 



Apart from the cost of the apparatus and the greater 



