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the inadequacy of the stream for the prompt removal of flood 

 waters, says : "This lack of capacity, while it explains the wide 

 and deep overflows, by no means implies that any large pro- 

 portion of the volume moves down the valley for considerable 

 distances except in the river bed. The dense timber and the 

 vegetation in summer, the higher ground leading across from 

 the bluffs along every tributary, the occasional approach of 

 bluff, terrace, or ridge, the frequently returning sloughs from 

 interior ponds and lakes, all forbid this. The bottoms are 

 really storage grounds to impound the flood waters that arrive 

 faster than the channel can carry them away, and they prolong 

 the floods in some inverse ratio to the reduction of volume." 



Observations made in the course of field work during the 

 floods of 1896 to 1900 at Havana, lead me to suggest that there 

 may often be developed a fair current outside of the channel 

 of the main stream in such localities as Thompson's, Flag, 

 Quiver, and Phelps lakes (Plate II.), where a considerable reach 

 of open territory lies in the general direction of the main cur- 

 rent. Even in the wooded districts the current may not be 

 wholly absent, though it is often very slight. 



The duration of the overflow in various parts of the valley 

 illustrates the reservoir action of the bottom-lands. In the 

 period from 1883 to 1889 the river was out of its banks at Morris 

 60 days, or 8.5 days per year; at Copperas Creek, for 444 days, 

 or 63.5 days per year; at LaGrange, 526 days, or 75 days per year. 

 I quote from Cooley ('91) the following discussion of this subject: 

 "A better appreciation of the reservoir action, or equalizing 

 effect, of overflows may be obtained by a consideration of the 

 impounding area of the bottoms. An area of 704 square miles 

 submerged to a uniform depth of four feet — this is a flood height 

 of sixteen feet and not an unusual occurrence — represents 1.21 

 inches of water running off the entire watershed, and will sup- 

 ply the river at the rate of 110,000 cubic feet at the mouth for 

 8.26 days, or at half this volume, which is an approximation to 

 the true maximum discharge, for 16.52 days. An overflow of 

 eight feet, or a flood of twenty feet, which is an extraordinary 

 occurrence, represents 2.42 inches of water running off the 



