MOSQUITOES AND DISEASE 95 



stance of failure has occurred in the disinfection of these small 

 towns, and the result of the whole work has been the apparent 

 elimination of yellow fever and the very great reduction of 

 malarial fever. 



The remarkable character of these results can only be judged 

 accurately by comparative methods. It is well known that 

 during the French occupation there was an enormous mortality 

 among the European employees, and this was a vital factor in 

 the failure of the work. 



Control by School Children. — That children can be of im- 

 mense service in freeing a city from mosquitoes as well as from 

 house flies (see Chap. VIII) is illustrated by certain events that 

 took place in San Antonio, Texas. Yellow fever appeared in 

 this city in November, 1903, and although its presence was 

 denied by the inhabitants, efforts were made by certain enlight- 

 ened people to eradicate it as soon as possible by destroying all 

 the mosquitoes. In this campaign the aid of the school children 

 was enlisted with excellent results. 



The best recent literature on the subject of fighting mosquitoes 

 was procured and furnished to the teachers, and a circular letter 

 was sent to them outlining a proposed course and offering a cash 

 prize for the best model lesson on the subject. Teachers became 

 deeply interested. A crude aquarium, with mosquito eggs and 

 larvas was kept in every schoolroom, where the pupils could 

 watch them develop, and large magnifying glasses were fur- 

 nished in order that they might study to better advantage. 

 The children were encouraged to make drawings on the black- 

 board of mosquitoes in all stages of development. Lessons were 

 given and compositions were written on the subject. Competi- 

 tive examinations were held, and groups of boys and girls were 

 sent out with the teachers on searching expeditions to find the 

 breeding places. Rivalry sprung up between the ten thousand 

 public school children of the city in the matter of finding and 

 reporting to the health office the greatest number of breeding 

 places found and breeding-places destroyed. Record was kept 



