THE MICROBES OF HUMAN DISEASES. 171 



the reason why these men seem to enjoy an immunity 

 from most contagious diseases. 



People are too much disposed, when an epidemic 

 is prevalent, to accuse the privies, of which the 

 emanations are, under ordinary circumstances, only 

 offensive to the smell. When these places, as well as 

 the sewers, are properly constructed, they present no 

 danger. But it is necessary that there should be 

 a sufficient flow of water in both to cover the solid 

 matter. We know, in fact, that if microbes are present, 

 they only become dangerous when dry enough to float 

 in the air. 



In an epidemic of typhoid fever, for instance, the 

 soiled body and bed linen of the patient are much more 

 dangerous than the privies, in which, however, there 

 is a much larger number of microbes. The linen, 

 therefore, as well as the contaminated rooms and 

 furniture, should be immediately disinfected in the 

 mode prescribed by sanitary authorities. 



The system of directing everything to the sewer, 

 which is now universally applied to large towns, and 

 which has encountered much opposition, is certainly 

 excellent when properly understood and applied. The 

 cesspools, as well as the cemeteries, ought to be as 

 remote as possible from the houses of the living. It 

 is as much opposed to public health to retain cesspools 

 which are gradually filled in the course of years, in 

 the midst of a town, as to have intramural cemeteries. 

 Everything should be carried off by the sewer, pro- 



