ANTIMALARIAL WORK IN COLON 83 



inspector ; these men keep in touch with the district 

 inspectors, and act as teachers. Each district inspector 

 has a gang of twenty-five to thirty men, who trench 

 and cut bush, also carpenters for looking after screening ; 

 lastly two quinine dispensers. The medical officer of 

 each district reports monthly all cases of malaria to 

 the central office, and if the number of cases go up in 

 a district there is an immediate inquiry to know why. 



THE ANTIMALARIAL CAMPAIGN IN COLON 



Colon is a town of 15,000 inhabitants, built on 

 an island just above sea-level, and many of the houses, 

 as in similar low-lying countries, viz. Honduras and 

 British Guiana, are built upon piles, and in the wet 

 season swamps abound, and of course innumerable 

 mosquitos. The bush was first cut away for half a 

 mile to the back of the town ; the cleared swampy area 

 was then canalised and small superficial drains led into 

 the larger channels ; with the fall of the tide the fresh 

 water runs out, and the incoming tide brings in sea 

 water. I recommended precisely the same system 

 in British Honduras. All barrels and cisterns were 

 rigorously inspected. Result— Colon is to-day almost 

 free from every kind of mosquito. In addition, however, 

 tlie houses of employees are screened with wire gauze ; 

 mosquito nets are used, although the necessity for these 

 precautions has practically ceased ; quinine is also taken. 



ANTIMOSQUITO CAMPAIGN IN RIO DE JANEIRO 



The City of Rio de Janeiro furnishes us with 

 regular monthly returns which disclose a marvellous 



