564 STRATIGRAPHICAL GEOLOGY. 



Andover and Salisbury, upon the south-east side of the Kearsarge rocks. 

 This is hmited southerly by the Salisbury area of Lake gneiss already 

 described. That part of the area in the Merrimack valley north of Con- 

 cord may be regarded as belonging either to this or the next basin. 



The facts concerning this area above Campton have been set forth 

 upon pages 133-136. It would appear that the eastern portion of the 

 mass has generally the disposition of a synclinal basin, and that the 

 strike does not conform to that of the adjacent porphyritic gneiss. 

 Nothing is said about the exposures west of the river in Woodstock 

 and Campton. A portion of those in Woodstock are with difficulty 

 separable from the Lake gneiss. About half a mile south-east of Elbow 

 pond the dip is 80° S. 30° E. The rock is much contorted. The dip is 

 S. 85° E. by J. Downing's, in the south part of the town. At Hubbard 

 pond the dip is 75° N. 35° W. For about two miles through the middle 

 of the town, next the river, the rock is a wrinkled andalusite schist, like 

 that in Rumney. I have no observations relating to the occurrence of 

 this rock in Thornton, west of the river, but from what has been stated 

 it seems probable that the synclinal from the east passes near Hubbard 

 pond towards Rumney. 



The position of the rocks across Campton is portrayed in the delinea- 

 tion of Section VH. The first rocks west of the porphyritic gneiss dip 

 north-west; — as N. 60° W. in the south-east corner of Thornton, and 35° 

 N, 30° W. on the summit of Mt. Weetamoo. At the base of the moun- 

 tain the dip changes so as to produce a synclinal. This position is con- 

 tinuous through to the river, giving us probably two foldings. Here is an 

 axis of porphyritic gneiss. On the first considerable hill west the dip is 

 southerly. This dip is so nearly like that in the east part of the town 

 that the axis is truly an inverted one. Near the west line the dip is 70° 

 N. 82° E., so that we have a synclinal here resting upon the older gneiss. 

 The character of the rock in the north-west projection of the town may be 

 known by stating the nature of the ledges proceeding south-westerly from 

 Bald hill to Rumney. At M. Cram's and W. Leavitt's is a mixture of fine 

 and coarse granites interstratified with the more micaceous layers, dip- 

 ping 30° E. At R. Pike's, in the edge of Rumney (or the school-house 

 south), the granite seams dip three degrees southerly. At L Chapman's, 

 more than a mile east of Rumney village, is the Concord granite variety. 



