THE ECONOMY OF REDUCTION 15 



examination is being carried out in order to prevent 

 mosquitos there will be no opposition. 



4. It interests the inhabitants, and encourages 

 them to notify sickness and the return of mosquitos 

 to the local authority. 



The cost is not great. It varies, of course, in 

 different countries, for it is dependent upon several 

 variables, such as the cost of labour, petroleum, etc. 

 But a municipal rate of sixpence per head of popula- 

 tion per year in large towns will generally cover the 

 cost of the upkeep of a mosquito campaign, though 

 this rate may be increased owing to a heavy summer 

 rainfall, much exposed infiltration water, irrigated 

 gardens or parks, and decreased by a complete system 

 of sewerage with good and constant pressure on the 

 town water-mains, and other factors. 



But if a mosquito campaign is persevered with its 

 cost will gradually diminish, as it has done at Port 

 Said. Then the organisation may be utilised for 

 further sanitary work. It will be a trained organisa- 

 tion, and can be taught to report on the presence of 

 diseases other than those conveyed by mosquitos ; it 

 can be made to examine unhealthy shops and over- 

 crowded factories, for example. But the original 

 idea must never be lost sight of. If the mosquito 

 work is neglected for a single week, the insects will 

 surely return, and then the work will fall into disre- 

 pute. Perseverance and constant attention and 

 supervision are necessary for success ; but these, 

 with the money expended, will be amply repaid by 

 the improved health and comfort of every one. 



