38 



or isolated bayous, but su<h form in time of droiijiht. resiiltiiiji; in a de- 

 struction of the minnows and the development of countless numbers of 

 mosquitoes. 



Mosquitoes : Mosquitoes occurred in immense numbers in the early 

 days, when breeding places were plentiful. They were common along tht 

 canals, and an English traveler on the Wabash canal, in 1851, writes of 

 them : "After tea, we all began a most murderous attack upon the mos- 

 quitoes that swarmed on the windows and inside our berths, in expecta- 

 tion of feasting upon us as soon as we should go to bed. But those on 

 wdiich we made war, were soon replaced by others ; and the more we killed, 

 the more they seemed to come to be killed, like Mrs. Bond's ducks ; it was 

 as though they would defy us to exterminate the race. At last, we gave up 

 the task as hoi)eless, and resigned ourselves, as well as we could, to pass a 

 sleepless night." He adds : "What with turning about on account of the 

 heat and trying to catch the mosquitoes, who bit us dreadfully, we did not 

 get nmch rest ; and we rose the next morning unrefreshed." 



Canals were a factor in the mosquito-malaria problem. In some of the 

 older States it was noticed that malaria followed the canals, that the dis- 

 ease appeared where it had formerly been unknown ; in other places it 

 markedly increased its prevalence; some towns were almost depopulated. 

 When Indiana undertook to build canals tlie malaria question was not over- 

 looked ; there was opposition. The reservoirs were considered especially 

 obnoxious, and in places, notabl.v in Clay County, the people began to de- 

 stroy them ; State trooiis had to be called out to protect the embankments ; 

 the Legislature even appointed a connnittee to inquire into the matter and 

 report. This conmiission, and medical men generally, tried to minimize 

 the supposed evil influence ; in tlie light of the then prevalent decaying- 

 vegetatiou theory they could not see how canals or reservoirs could in- 

 crease the disease. Today we can readily see that the popular belief rested 

 on good foundation ; the reservoirs and the small ponds made on account 

 of the embankments at gidleys or ravines, formed breeding places for mos- 

 quitoes. The larger ponds in the course of time became inhabited iiy fish 

 and thereby lost their mosipiitoes. but in the smaller ponds with a period- 

 ical drying out, fish could not live. 



It was noticed that canal-boat men suffered less from the disease than 

 tlie people along the banks, and this at first sight seems difficult to explain. 

 But the explanation is simi)le ; it is analogous to the explanation of why 

 railway conductors and porters eeem healthy in spite of their exposure to 



