126 WALOOMSAO EIVEE. 



The cement is carbonate of lime, derived from the limestone in the neighborhood, infiltrated into the 

 gravel in a state of solution, and uniformly diffused through the mass. This cement is discovered only by 

 the application of an acid, when a brisk effervescence ensues. The stratification of this solid mass is as 

 distinct as that of any of the older consolidated rocks. 



The dip of this rock is explained by original deposition. The valley is quite narrow, and must have been 

 very deep when the conglomerate, which is the lowest part of the terraces, was forming ; consequently the 

 materials that were brought from the northwest were deposited on a slope, like the loads of gravel, etc., 

 added to the steep slope of a railroad embankment. Perhaps, also, the reason why only part of the terrace is 

 consolidated, is due to the character of the underlying rock. The hill back of the terrace is micaceous schist 

 underlaid by limestone. As the limestone is in the lowest part of the valley if the cement was obtained 

 from this rock, in place, after the deposition of the terrace, we should expect that its influence would extend 

 only so far above the level of the river as the rock extended. The exact thickness of the limestone at this 

 point has not been ascertained, and perhaps we might apply the converse of our proposition to determin- 

 ing the height of the limestone ; if so, the suggestion would serve two important purposes. 



Beyond this bend in the river, the valley widens, and with it the first terrace, until there is an extensive 

 plain at South and North Pownal. As Hoosac Eiver is mostly located in other states we have not traced 

 out the number of basins upon it, but without hesitation we can say that there is at least one distinct basin 

 of terraces upon it in Vermont. 



Going to the north, we next come to the Waloomsac Eiver, which rises in Pownal, passes through 

 Bennington and unites with the Hoosac Eiver near Eagle Bridge, in New York. At North Bennington, 

 the valley of the Waloomsac is narrow, owing to the presence of silicious limestone, which has been cut 

 through with difficulty. A small terrace is seen, which corresponds to No. 2. Numerous small bowlders 

 of quartz rock are seen, which have been brought from the east part of Bennington and Woodford by the 

 action of the river. They are all water-worn, and furnish an illustration of the character of modified drift, 

 when compared with unmodified drift. In East Bennington, or in the center of the territory of the town, 

 the meadow of this river spreads out and is bounded on its edges by a second terrace. It is the plain upon 

 which East Bennington 1s built, and both terraces together constitute a basin. 



The main stream continues to Barbar Pond in Pownal ; the upper portion of its course exhibiting many 

 large moraine terraces. The Woodford branch passes through the quartz range directly east from Ben- 

 nington, and has its banks and rough terraces composed of drift bowlders scarcely modified, and underlaid 

 by tertiary deposits. Like the materials at the foot of the Green Mountain range from Connecticut to 

 Starksboro, Vt., so here, bowlders of the metamorphic quartz rock are grievously abundant. 



A small tributary creek of the Waloomsac at North Bennington, which follows the Western Vermont 

 Eailroad to Shaftsbury, has finer terraces upon it than any other branch. They amount to four, nortli of 

 South Shaftsbury, and are succeeded by an old sea beach or sea bottom, at the summit level at Shaftsbury 

 Center. A large part of the coarse gravel constituting the first and second terraces, between North 

 Bennington and South Shaftsbury is consolidated, like that at Pownal. We suppose the cementing sub- 

 stance to be the same carbonate of lime although there is a great amount of the peroxyd of iron 

 present, which gives its characteristic yellowish color to the whole mass. We presume from these tw 

 cases of consolidation, that in the limestone region west of the Green Mountains, especially when near the 

 tertiary beds of hematite, consolidated masses of gravel and sand are common. 



Passing over the sea beach in Shaftsbury Center at the Eailroad station we see a very high terrace, 

 composed mostly of sand, in the middle of the valley, forming a sort of a ridge. It slopes to the north four 

 or five degrees, and may be followed to Arlington Center, where it caps the hill east of the railroad. It 

 seems to us rather to have been formed by some other agency than any existing stream either some larger 

 stream or the ocean, as it is continuous from the old sea beach in Shaftsbury to Arlington. We have 

 marked it on the map as the fourth terrace on the Battenkill Eiver at Arlington, continuing south to 

 North Shaftsbury, and it certainly is the fourth terrace at Arlington. With this so called terrace, are 

 sometimes associated moraine terraces. 



