24 NEW YORK STATE MUSEUM 



erosion. Where the Hoosic river has cut deep into the delta, form- 

 ing a succession of terraces on either side of the valley, thus expos- 

 ing the materials of the delta at different levels and at varying dis- 

 tances from the head of the delta at Schaghticoke, they differ con- 

 siderably from the materials of the surface of the plain. In gen- 

 eral, the terraces of the lower levels are of mixed clay and sand 

 composition, forming soils which are well adapted for farming and 

 gardening. For instance, the extensive fiat at the lOO-foot level 

 crossed by the road running northeasterly from Reynolds is com- 

 posed of fine-grained soils of high fertility. The materials of the 

 terrace plain on the opposite side of the river, beyond the alluvial 

 flat and rising to the 140-foot level, are also finely divided and 

 include a considerable proportion of clay in their composition. 



The fine sands and clays, lying at the base of the delta deposits 

 and far out from the head of the delta, are interpreted as the 

 bottom-set beds of the formation. They were laid down at an 

 early stage in the building up of the delta, representing the finer 

 sediments borne by the Hoosic river and dropped where the cur- 

 rents were checked by the quiet waters of the body of the lake. 



The materials of the higher terraces become progressively 

 coarser in order of elevation and of nearness to the head of the 

 delta. This is well shown to the observer who follows the road 

 south of the river, beginning where the road crosses Tomhannock 

 creek and continuing eastward and southward to the 360-foot level 

 of the delta plain beyond where the highway crosses the railroad. 



~~\y 



Fig. 4 Profile of terraces in delta of Hocsic river. The terraces south 

 of the river are shown on a line extending from the delta plain west of 

 East Schaghticoke to the Hocsic river at the mouth of the Tomhannock 

 creek; the terraces north of the river on a line extending from the latter 

 point northeasterly to the delta plain northwest of Schaghticoke. See lines 

 on map. 



Thus the materials of the successive terrace plains were noted as 

 follows: 140-foot terrace, sandy loam; 180-foot terrace, coarse 

 sandy or loamy soil; 220-foot terrace, fine to coarse gravel; 320- 

 foot terrace, gravel, largely uncultivated; 360-foot level (south of 

 railroad), sand and fine gravel. The materials of the terrace plains 

 on the opposite side of the river are predominantly sand and gravel, 

 although the extensive plain at the 340-foot level has a considerable 

 admixture of clay. To the east of the ravine, however, this plain 

 gradually merges into an area of blown sands. 



