ERODED TERRACE. 



115 



terrace has assumed by the wearing of a small stream. Our attention was called to it in 1857 by 



Seminary, who kindly showed us also other 



Fio. 61. 



Erosions in a Terrace in Haverhill. 



the Rev. C. W. Gushing, A. M., President of Newbury 

 points of interest in the neighborhood, and subse- 

 quently sent to us specimens of rock from his vicinity. 

 The elevations are indicated by lines, the valleys 

 constitute the remaining part of the figure. Origi- 

 nally, the whole was of the same level as B B, or 

 terrace No. 6 ; but the valley through which the 

 sluggish streams A A pass, in a morass, is fifteen to 

 twenty feet below the surface of the terrace. A few 

 feet of C C have been removed. From the elevated 

 land B upon the left of the figure, a sort of a hook 

 runs around a similar hook, extending from C C. The 

 strip from B upon the left, is nearly worn away, a 

 bank of only about three feet depth and four feet width 

 remaining to connect with the extreme point C. 

 This narrow neck must have been worn by the 

 current on the left hand, as it is directly in its 

 natural route, as the arrow indicates. The agency by which the sand has been thus singularly 

 removed must be water, and that from occasional freshets, as this spot is near the head waters of the 

 stream. But the sand is so light that a very gentle current would easily remove it. Had the current been 

 stronger, doubtless the excavation would have been more nearly straight. Passing to the north, when 

 above the terraces, we come to an old beach, whose counterpart upon the opposite shore of this former 

 narrow estuary, may be found upon the hills west of Newbury, at a height of 1488 feet above the ocean. 



Jumping upon our Geological Train again at Newbury, we pass by ledges of slate, fractured by the drift 

 agency, and arrive at Wells River. Here Wells River enters the Connecticut on the west side, and the 

 Lower Amonoosuc on the east. Hence these three rivers have accumulated much material, which is 

 arranged in terraces on each, there being four terraces upon each side of the three rivers. Those on the 

 Connecticut diminish in size and finally become obsolete at the south line of Ryegate, where a gorge 

 succeeds. 



The fifteenth basin extends through Ryegate to Mclndoe's Falls in Barnet, a distance of eight miles. 

 The terraces are of less size than those in the fourteenth basin, and generally the fourth terrace is wanting 

 entirely on the east side, except a limited fragment at Canoe Falls, where there is also a kind of a beach. 

 The fourth terrace extends the whole of the distance on the west side, and is generally accompanied by 

 others. 



At Mclndoe's Falls commences the sixteenth basin, where rock forms the western bank, and the third 

 terrace the eastern. The terraces are generally small and scanty, amounting, however, to five in number, 

 where the Passumpsic River empties into the Connecticut. We seem, however, to have entered upon a 

 district where the bed of the river is mostly rocky, relieved occasionally by a few feet of soil. There are 

 several falls on this basin, and indeed before its northern limit is reached, commences .the " Twenty Miles 

 Rapids." Although to a geologist's eye the terraces are very few in number in this basin, it is evident that 

 the farmers of this region think otherwise. Hence their enterprise has given birth to an invention, which 

 is not patented, we believe. Mr. Enos Stevens of Barnet, a son of Henry Stevens, Esq., not willing to wait 

 for the slow operations of nature to work out their results, has applied reason to assist inanimate matter. 

 Upon his land there was a high bank and a piece of low wet land, neither of which were of any great value. 

 Near by is a small stream which had been doing what it could, in its senseless way, to wear down the bank. 

 But like other brooks, this one was of little use to accomplish this work, because it was so small. Mr. 

 Stevens saw that he might assist in this work. Therefore he changed the course of the stream in the time 

 of a freshet, making it pass through that portion of the bank most easily removed. Obedient, the stream 

 can-led down the gravel and sand into the low land, and, by regulating the course of the stream for a time, 



