312 SURFACE GEOLOGY. 



Another style of disturbance is indicated in faults, some of which have 

 been referred to upon page 39. Many of them can be regarded as the 

 result of local sliding. One more difficult to explain may be seen be- 

 tween Mink brook and the village of Hanover upon the West Lebanon 

 road. The first bank next the brook, below Mr. Benton's house, dips 10° 

 northerly. Near the base of the principal hill, north of Benton's, the 

 dip is southerly at the same angle. Near the top the stratification is 

 horizontal. The section along the road shows the loamy sand to have 

 a synclinal structure, or, rather, there are two faulted segments dipping 

 towards each other. Other highly inclined masses of alluvium occur 

 close by the railroad depot in Norwich, at the north edge of the great 

 plain two miles from Dartmouth college on the Lyme road, and near the 

 mouth of Grant brook in Lyme, where the angle of inclination amounts 

 to thirty degrees. It seems likely that the forces disturbing these ter- 

 races were analogous to the elevating agencies that displayed their power 

 in the earlier periods of geological time. Earthquakes of greater severity 

 than are now common in the state might have been adequate to produce 

 the results. The facts are given to draw the attention of other and future 

 observers to the subject, as they may find more important illustrations of 

 a continental force, or else discover satisfactory evidence that the dis- 

 turbances have been entirely due to gravity. 



Ice Accumulations. 



Occasionally the conditions are favorable for the continuation of ice 

 unmclted through the entire summer. The best known example is in 

 Tuckerman's ravine, described in Volume I, page 623. Here it is ex- 

 posed to the sun and air, continuing very long because of an immense 

 accumulation. In other cases the ice is preserved in caverns, or in the 

 midst of large fragments of rock, as in Lyman, Effingham, and Plymouth. 



In Lyman, about half a mile west of Parker hill, ice accummulates 

 beneath large stone fragments at the base of a cliff. I found no ice there 

 September 4, 1870, though the air issuing from the side was very cold, 

 indicating its existence. The people in the neighborhood often obtain 

 ice from this locality in the summer. In a journal published in Concord 

 in 1823, it is related by Caleb Emery, of Lyman, that in 18 16, a mem- 

 orable cold summer, he saw a well frozen over solid, eight feet from the 



