THE OSCILLATIONS OF THE CONNECTICUT. 733 



for some little distance above the bridge. I have alreiulv litul oc<'asioii to 

 describe the meadows as formed by a coutiuued repetition of this process. 

 (See %. 47, ]). 72(i.) 



ON THE OSCir,t,ATIONS OF THE COKNECTICUT FROM ITS EARI.IEST 



POSITION. 



From the north line of the State to the Snnderland bridge the river 

 everywhere cut down rapidly to rock and has not swung wideh' to east 

 and west, but has been coudenmed from the beginning to rock cutting. 



The river at the beginning took its course across the Hadlev Lake 

 bottom along the deepest line, which it has obliterated. I imagine that this 

 line was very near its present position. It jjrobably s\vung first eastwardlv 

 to its eastern limit, at the "halfwav house" on the Hadley road. It is 

 more certain that from this eastern limit of its oscillation it has moved west 

 reg'ularly and silted up its lied Ijehind quite rapidl}^ and completely; 

 this is shown hj the fact that the Hadley and North Hadlev-Sunderlaud 

 meadows are composed of series of elongate and coalescing islands, as 

 detailed on page 726. It has swung, then, west across the Hatfield and 

 very far west across the Northampton meadows, and regained again a more 

 central position by cutting off its oxbows. During its swing westward, 

 across the Northampton Meadow and back, it has lowered itself by about 

 7 feet more than its own depth, since at the foot of Hadley street its old 

 bottom sands rest upon the eroded surface of the Champlain clays at a 

 height of 7 feet above the low water of the river. This height may be some- 

 what increased if w^e allow for the influence of the Holyoke dam. 



From the Holyoke notch south to the Holyoke dam the river early 

 became entangled in rock and has cut only vertically. From the dam south 

 the earliest position, or, more accurately, the earliest restorable position, 

 may be found by following down the outside edge (counting from the river) 

 of the oldest terrace of erosion (t^). This, the highest terrace of this later 

 series, is found only on the west side of the stream from Holyoke south, 

 and then is for a long way present on the east side, across Springfield, then 

 being transfeired to the west side, across Agawam. This represents the 

 sinuous position of the stream from the Holyoke Falls southward at a time 

 when it had first established its course across the lake bottom, and from 

 which it has swung to form its later and lower terraces, ending in its present 

 temporary position. 



