FUMIGATING THE MOSQUITOS 145 



screened. Incomplete and imperfect fumigation are 

 the principal reasons of not being able more promptly 

 to suppress yellow fever. 



Houses and huts in tropical countries have usually 

 innumerable large and small openings in roof and sides, 

 and it is contended that it would be difficult to seal 

 them, or halls, stores, or markets without elaborate and 

 expensive wooden framing. As a matter of fact, and 

 proved in numerous instances in tropical countries, an 

 intelligent workman can, in an incredibly short time, 

 paper over a whole archway, hall, or even court. 

 By the use of a few supporting laths, and with stout 

 and thin paper, the very large openings can be com- 

 pletely sealed. The stout paper necessaiy for covering 

 large openings can usually be procured locally and at 

 once. Paper cut in rolls, three inches wide, is exceed- 

 ingly useful for pasting along the cracks, but it would 

 be required to be ordered and to be kept in stock. In 

 an emergency, however, strips of newspaper could 

 readily be cut. Although it is recommended to seal 

 the rooms from the inside, I think there is an advantage 

 in sealing windows, etc., from the outside in order not 

 to disturb any mosquitos which may be present. If 

 there are any fireplaces or other holes they will require 

 to be sealed from the inside. The doorway is left 

 open till the last to introduce the fumigating materials 

 and to light up ; when this has been done the door is 

 brought to and sealed, and the time noted in a book 

 kept for the purpose. The medical officer or the chief 

 superintendent should personally examine to see that 

 the sealing is carried out effectively. A small open 



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