652 STRATIGRAPHICAL GEOLOGY. 



Cuba rests upon Bethlehem gneiss, the first indicating a basin form, and 

 there being a well marked anticlinal between the two quartzites. Fig. 5 1 

 shows facts of stratigraphy in a section from Mt. Cuba to Orford street, 

 a little to the north of our route of examination. The Bethlehem range 

 is well marked west of the Cuba ridge. It contains an important bed of 

 limestone, and exhibits one or two folds, the undulations being less marked 

 here than farther north, because more compressed. West of Bass hill the 

 particular features of this section as far as Connecticut river are shown 

 in Fig. 52. These are, first, two foldings in Coos schists; second, an 

 underlying patch of Huronian with soapstone at Orfordville ; third, mono- 

 clinal Coos schists containing narrow bands of granite and hornblende 

 schist. Underneath the meadows of Orford and Fairlee there must be a 

 considerable amount of Huronian to connect the known outcrops of that 

 formation in North Thetford and Fairlee. The first rock visible to the 

 west of the modified drift is clay slate, near by the north end of the Hart- 

 ford and Thetford band. Next is a broad band of the Coos micaceous 

 quartzites, reaching as far west as Podunk pond in Strafford. Next the 

 eastern border of this group, in the extreme north part of Thetford, two 

 folds are obvious, while in Fairlee a synclinal band is indicated by the 

 divergence in the dips, 15° and 60° N. E. There is a new strike in the 

 strata about the Ely copper mine in Vershire, and also at a similar vein 

 east of Strafford. On comparing other copper veins with these, we find 

 a suggestion that the copper is either in or near an older hornblende 

 range, and hence we may be guided in determining the nature of the 

 foldings in the cupriferous region. West of Podunk pond, in Strafford, 

 the change in dip and rock is so abrupt as to suggest the presence of a 

 fault. The hill east of the Centre village appears like an inverted syncli- 

 nal of the mixed mica schists and limestones lying upon a hornblende 

 band. The characteristic limestones with easterly dips occupy the valley 

 of the Pompanoosuc in the middle of the town, and make an anticlinal 

 in the hill west. 



Section VIII. 



Section VIII may be said to begin at Bridgeton, Me., reach the New 

 Hampshire boundary at Kimball's pond in Chatham, pass over Mt. Pe- 

 quawket, and extend through the towns of Bartlett, Hart's Location, Liv- 

 ermore, Woodstock, Benton, and Haverhill to Connecticut river, thence 



