52 SURFACE GEOLOGY. 
the upper portion of the delta of Little Sugar river is of the height men- 
tioned. Its principal mass is 50 feet lower, being the terrace cut by the 
railroad one third mile north of the river. It is almost wholly composed 
of gravel, in which the largest pebbles are one foot in diameter. In the 
Fig. 14.—FoLpED CLAvEY LAYER IN HORIZONTALLY STRATIFIED 
GRAVEL, NORTH CHARLESTOWN. Scale, 1 inch—ro feet. 
midst of this gravel a stratum 14 to 3 feet thick, consisting of clay ‘in 
layers a third of an inch thick, interstratified with a clayey sand, was 
exposed for 75 feet on the west side of this cut. Along half this distance 
it was levelly stratified, but beyond was irregularly crumpled, as shown 
in Fig. 14, apparently by lateral pressure. 
The wide, high delta of Black river has been cut through by Button 
brook, and has been variously terraced both by this brook and by Black 
river. A considerable portion of its plain between these streams is cov- 
ered by heavy white pine woods. ‘This delta increases the height of the 
upper terrace for more than two milés southward. The delta of Williams 
river is less extensive than the preceding, and at the same time has léss 
thickness, as it has been partly protected from erosion by ledges, which 
in some places form its border. 
Two miles north from Williams river the west bank of the Connecticut 
exhibits an interesting section (Fig. 15) of synclinal strata of clay and 
~«vxes  sand eroded to a level top, and over- 
52, laid by levelly stratified sand. The 
{ synclinal deposit appears to be the 
lower part of that which once filled 
Fig. 15.—SECTION OF RIVER-BANK, ie a * saat oe 
-RockincHam, Vr. Se Vea teh the valley. After its upper portion 
“too feet. ‘had been carried away, the overlying 
sand was brought in by a tributary, and subsequently terraced by the 
river. The most noticeable feature of the modified drift north and south 
from here is the wide interval or meadow, which extends from Charles- 
town village to Bellows Falls, and lies partly on éach side, being several 
times crossed by the river. 
