, IOWA ACADEMY OF SCIENCES. • 19 



where, we are enabled to use that must be considered. All that 

 may be said in reference to constancy of our climate and the 

 average uniformity of our rainfall may be granted, and yet I 

 believe that the problem I have broached is a real one, a very 

 real one, worthy the consideration of this body and demanding 

 now the most serious attention at the hands of this whole 

 people. The rainfall may be absolutely constant, or subject 

 only to variations such as are continental, planetary if you please 

 in origin, and yet the amount of moisture available for use in any 

 particular locality for any given time may depend on causes lohich 

 may be traced wholly or in great part to human agencies. 



Such cases are, therefore, under our control. As I have 

 already remarked, our methods of agriculture affect in pro- 

 foundest fashion the recipient and retentive characters of the 

 ground. 



Permit me to carry my argument a little further. Our 

 streams are threatened because we have cut off their sources 

 of perennial supply. Omnipresent drainage and tillage has 

 affected, is affecting, more and more their constancy. 



The question of general humidity interests primarily the 

 farmer, and the farmer is mainly responsible for present condi- 

 tions and tendencies; but, the existence of our rivers affects 

 those of the city perhaps even more than those of the tield. 

 Along the Iowa river for instance are Eldora, Iowa Falls, Mar- 

 shalltown, Iowa City, and other towns of only less importance, 

 all dependent upon the river for their water supply. The Iowa 

 river rises in Hancock county. Until within a few years 

 that county contained thousands of acres of marsh land, peat- 

 bogs, lakes, among which Eagle lake was large enough to 

 receive a name. What is the situation now? The marshes of 

 Hancock county have been drained, the peat-beds support har- 

 vests of grain, and Eagle lake has given place to corn fields over 

 which passes, autumn and springtime alike, the farmer's tri- 

 umphant plow. The history of smaller tributaries to the river is 

 precisely the same, all the way until it receives the Cedar and 

 finally pours a diminished flood into the Mississippi. The same 

 thing is true of the Skunk river, the Coon, the Des Moines; 

 and yet cities not a few are dependent more or less entirely on 

 these streams for water. This is aside from all interests the 

 farmers have in the streams, interest practical or theoretical. 

 It may be said that the cities have resources; they may sink 

 artesian wells. But we have yet to prove that this is practic- 



