37 



Out of the many diseases and afTectious that come uuder one or the 

 other of the abo\'e groups. I desire to malce mention of only two, namely, 

 malaria, already referred to, and tuberculosis — one a decreasing, the other 

 an increasing disease. 



Malaria: Malaria was the Grendel of the early ludianians. Today 

 we can scarcely realize what the disease meant to the early settlers ; in 

 some localities it ravaged frightfully. Thus in the early history of our cap- 

 ital city we read that the forest was cleared in 1820 and lots laid out and in 

 the spring of 1821 the immigrants rushed in to the number of six hundred 

 or more. In the latter part of July malaria appeared, and. I quote from 

 Dralve. "iiefore tlie epidemic closed in October, nearly every person had 

 been more or less indisposed, aud seventy-two. or about an eighth of the 

 population, had died." In some localities the disease was so severe that 

 farming lands couUl not be sold, and for a long time immigration to our 

 State was retarded ; people went through to Illinois, to the prairies. 



In an account of the diseases prevailing in Indiana in 1872, by Dr. 

 Sutton, it was noted that the summer was dry. and in comparing reports 

 from different counties of the State it was found that malaria had been 

 more prevalent than usual in some of tlie rolling southern counties and in 

 places along streams and I'ocky creeks, wliile. on the other liand. it was 

 less common than usual in tlie nortliern <'ounties whei'e before it had been 

 very common (liut \\l)ere ;lr:unas:e liad made some of the worst places sa- 

 lubrious). At that time the view tlia.t decaying vegetation and moisture 

 had a causative in'iuence was universail.^• believed, yet that theory did not 

 explain the conditions. Today, in tlie light of the role the mosquito plays 

 in the transmission of malaria, we can readily account for the facts. 



In the rolling southern connlies many of the small streams are fed by 

 springs which how a small volume at all times, but in dry sea.sons not 

 sufficiently to create a current in the rocky creeks ; hence many pools 

 formed, aud those pools ser\ed for breeding places for mosquitoes. Or- 

 dinarily e\'en a small continuous curr-^'nt of water will prevent the devel- 

 opment ol mosquito eggs, and ^^•e nuist keep in mind the presence of fish 

 and insects which feed on the mosquito larva, but which die off in times 

 of low water, on account of its stagnacy. In the wet northern counties 

 the drought meant a drying out of the breeding places of the mosquitoes, 

 with a consequent reduction of the nmnber of insects and of cases of ma- 

 laria. The same reasoning holds for the increase of malaria along the 

 larger streams ; in ordinary stages of water there may be no stagnant pools 



