56 3WS QUI TOES 



of the experiment. The peo})le in the surronnding coun- 

 try generally became feverish and ill, which meant simply 

 that tliey Avere all full of malaria, and the chilling- caused 

 by the rain brought about an explosion of the fever. The 

 experimenters, however, went out into the rain and got 

 soaked to the skin, but their health remained perfect. 

 Not the slightest trace of malaria developed in either of 

 them ; as above stated, the spot where the house was built 

 was probably the most malarious one in the whole Cam- 

 pagna, and it was situated on the banks of one of the 

 canals, which was literally swarming with Anopheles 

 larv?e. The prevalent idea that the night air of the Cam- 

 pagna is in itself so dangerous was included in the ex- 

 periments and the windows were alwaj's left oi3en at 

 niglit, so that if the marsh air had anything to do with 

 malaria tlie}^ would have contracted it. 



A check experiment was carried on at the same time. 

 Anopheles mosquitoes which had been fed on the blood 

 of a sufferer from malaria in Eome, under the direction 

 of the Italian authority Bastianelli, were sent to London 

 early in July. A son of Dr. Patrick Manson, the famous 

 investigator who first i)roved the transfer of filaria by 

 mosquitoes, offered himself as a subject for experiment, 

 and allowed himself to be bitten by the mosquitoes. He 

 had never been in a malarious country since he was a 

 cliikl, but in due time was taken with a well-marked ma- 

 larial infection of the double tertian t3"i:)e, and micro- 

 scopical examination showed the x^resence of numerous 

 parasites in his blood. 



No more perfectly practical demonstration is probably 



