38 



or isolated bayous, but siu b torui in time of drougbt, resultiujj; in a de- 

 struction or tbe minnows and tlie development of countless numbers of 

 mosquitoes. 



Mosquitoes : Mosquitoes occurred in immense numbers in tbe early 

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

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

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

 quitoes that swarmed on the windows and inside our berths, in exi^ecta- 

 tiou of feasting upon us as soon as we shoidd go to bed. But those on 

 which 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 nuich 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 tlie 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 the 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- 

 stro.y them ; State troops had to be called out to protect the embankments ; 

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

 report. This commission, and medical men generall.v. tried to minimize 

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

 vegetation 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 I'eservoirs and the small ponds made on account 

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

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

 and thereby lost their mos<iuitoes. 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 

 the 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 iiorters seem healthy in spite of their exposure to 



