Mosquitoes and Malaria 107 



For instance, we find some of the very early 

 writers emphasizing the point that swampy locali- 

 ties should be avoided for they produce animals 

 that give rise to disease, or that the air is poisoned 

 by the breath of the swamp-inhabiting animals. 



These views of the origin of the fever prevailed 

 until about the beginning of the eighteenth century 

 when the recently discovered microscope began to 

 reveal the various kinds of animalculae to be found 

 in decaying material. 



In 1 7 18 Lancisi held that the myriads of insects, 

 particularly gnats or mosquitoes, that arose from 

 such swampy regions might carry some of these 

 poisonous substances and by means of their pro- 

 boscis introduce them into the bodies of the people, 

 and although he had made no experiments to test 

 the assumption he did not consider it impossible 

 that such insects might also introduce the smallest 

 animalculae into the blood. It took almost two 

 centuries of study and investigation before this 

 guess was proved to be right. 



One reason why the mosquitoes were not earlier 

 associated with these diseases was that all who in- 

 vestigated the matter at all turned their attention 

 to the bad condition of the air in these swampy 

 regions. Malaria means bad air. We all know 

 that we can see the mists arising from such regions, 



