REMEDIES AGAINST MOSQUITOES 199 



In the summer of 1900, at a certain army post, about 

 one-half of the soldiers were ill with malaria. The hospital 

 was not screened, Anopheles were found upon the walls of 

 the malarial ward, bit the malarial patients in their beds, 

 flew out and bit the sentry on guard, and generally be- 

 haved themselves in a highly indecorous manner. The 

 early part of the summer was wet, then came a long dry 

 spell. After the drought had continued for some weeks I 

 visited the post, and within a few hundred feet of the 

 door of the hospital found a slight depression in the 

 ground which had contained a surface-pool of water. The 

 water had entirely evaporated during the dry spell, but 

 the drying mud at the bottom was fairly carpeted with 

 the empty jDupa skins of Anopheles. This was the only 

 trace of the early stages of Anopheles found in the 

 vicinity. This small depression could have been filled up 

 with two cart-loads of earth, and had this been done at 

 the proper time it would not have been responsible for the 

 birth of a single Anopheles, whereas it had been respon- 

 sible certainly for several thousands. This is as good an 

 example as could be desired of the desirability and feasi- 

 bility, as well as economy, in many cases, of filling up 

 breeding-places with earth. 



There can be no doubt that there are many cases where 

 a little drainage-work such as was done in the Maryland 

 town, or a little filling-in such as was needed at the army 

 post, will accomplish striking results in the way of reduc- 

 ing the numbers of mosquitoes. There are also many 

 other places where drainage or filling-in upon a large 

 scale would be desirable and necessary. It is difiicult in 



