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inmates of the house, the larvae can be destroyed in their 

 presence by pouring a few drops of kerosene or eucalyptus 

 oil on the surface, as described in paragraph 14. The same 

 can be done with larvae found in pools on the ground, or in 

 the pits so frequently used by natives for washing clothes 

 in. After the oil has killed the larvae, it evaporates, leaving 

 the water as fresh as before. 



At the rate of fifty houses a day, a gang of five or six 

 men will, in a few months, collect most of the broken pots 

 and tins in a town of considerable size. If funds allow, 

 and if greater rapidity be desired, several similar gangs, 

 each under its own head man, must be employed. 



When the gang has cleared all the houses within the 

 area of operations, it must begin at the first house and go 

 over the whole ground again. But at the second visit its 

 progress will be more rapid, because there will not now be 

 so many vessels to collect. Moreover, many of the inhab- 

 itants will have now learnt to destroy their own larvae. 



If the brigade is supported by voluntary contributions, 

 it is only just to appoint special men to destroy larvae in 

 the houses of the principal contributors and their neigh- 

 bours. This can be done while the combined gang is 

 collecting vessels throughout the town. Later on it will 

 probably be possible to extend this system, and to appoint 

 a special man to keep down the mosquitoes in each block 

 of buildings. One man ought to be able to deal in this 

 manner with about four hundred houses, visiting sixty or 

 more daily. But this can be done only after most of the 

 broken bottles and tins have been collected. 



People should be encouraged to report the presence of 

 numerous mosquitoes in their houses. When this is done, 

 trained men can be sent to find the cause of the invasion. 



