First Sanitary Work 289 



alone do not rid a Central American community 

 of them. Rain water is soft, and people were 

 accustomed to use it. The widespread custom 



A firmly supported eave-trough. 



of collecting and keeping it was difficult to 

 eradicate. 



Aedes calopus breeding also occurred in the 

 eave-troughs, which sagged, and were difficult to 



19 



