CHAPTER XXI. 

 TERRACES AND MODERN DEPOSITS. 



INTRODUCTION. 



An inspection of tlie profile of the river (PL XXI) shows in a striking 

 way the ineffectiveness of the stream at low water and its effectiveness at high 

 water. At low water it enters the State 181 feet above sea level and leaves it 

 39 feet above, bnt of this descent of 142 feet a fall of 132 is expended at the 

 two dams and the French King Rapids, and 10 feet only in the intermediate 

 spaces, less than 2 inches to the mile, as this portion of the river is about 

 70 miles long. At high water it crosses the State line at 218 feet^ above 

 sea level and leaves the State 57 feet above sea level, a difference of IGl 

 feet, and of this only 83 feet is lost at its falls and rapids; 78 feet is divided 

 over the long stretches of the stream, a little less than 14 inches to the mile 

 on an average, though in reality the stream is divided into segments having 

 velocities which oscillate widely about this mean. 



This is the time of active work for the flooded stream, and much work 

 goes on beneath its turbid waters, which is immediately visible when these 

 waters subside, and much which has been unsuspected and which is not 

 readily recognized. The visible effects are the erosion of its banks, the 

 increase of its bars, and the spreading of a fine loam layer over its flood 

 plain. The invisible work is the scouring out of the channel and the trans- 

 portation through it of an unknown mass of sands, and then the building uip 

 of the old bars and shallows again in the old places so perfectly that one 

 does not suspect that they have been removed at all. 



' This high- water datum was taken from the North field ferry house. The following notices of 

 years of especially high water are taken from the Supplement of the Hampshire Gazette, November, 

 1895: "1801, great Hood of Connecticut River, called 'Jefferson flood;' 1843, April 15 to 18, great flood; 

 1862, highest water ever known in the Connecticut, known as the Lincoln flood ; all the houses on 

 Maple aud Kruit streets submerged." 



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