560 STRATIGRAPHICAL GEOLOGY. 



indigenous coarse granites. The south-east part is made up of the crys- 

 talHne twisted variety of gneiss. 2. There is a row of ovoid masses of a 

 fine-grained granite from Manchester to Mason, all having a similar char- 

 acter, and contained within the micaceous part of the formation. They are 

 the Amoskeag and Bodwell quarries to the north-east, that near Fletcher's 

 in the west part of Bedford, and those near the villages of Amherst, Mil- 

 ford, and Mason. This line is one along which those needing this material 

 may search for new localities. 3. There is a well marked anticlinal in 

 the south-eastern part of this range, confined to the twisted gneiss. It 

 would seem to commence near the west part of Candia, pass near the 

 north end of Massabesic lake, north of the city reservoir, Manchester, the 

 south-east corner of Bedford, Danforth's corner in Amherst, and the 

 south-east corner of Mason. 4. On both sides of this anticlinal is a very 

 coarse mica schist, different from the Rockingham group. It has not 

 been traced throughout the range, because attention was not directed to it 

 sufficiently early in our explorations. It is not distinguished on the map. 



Hampstead and Pelham Range. The east boundary of the Mer- 

 rimack district being rather indefinite in the south part of the state, 

 I will regard, for convenience, this gneissic area as its south-eastern 

 limit, and not describe the gneiss beyond Hampstead, so as not to 

 encroach upon the maritime district. This is an independent range. 

 In its character it is losing the peculiar features of the Lake gneiss, being 

 intermediate between that and the Concord granite. The range may 

 commence in Epping and terminate in Massachusetts, only a short 

 distance beyond the limits of our map. It terminates because covered or 

 surrounded at the southern end by the Merrimack schists. It begins 

 very narrow in Epping, — if that is to be regarded as the same area, — and 

 at Hampstead it is two and a half miles wide. Its course at first is 

 almost south, but changes to south-west in Windham and Pelham. It is 

 eight miles wide from Nashua to Dracut, across the strike, and ten miles 

 in breadth on the southern border of our map. 



The eastern limit of the gneiss in Hampstead seems to be at the Con- 

 gregational church south of Wash pond, and a section across it to Derry 

 shows a monoclinal dip. At N. Hoyt's, half a mile from the church, the 

 dip is 50° N. 30° W., with beds of granite. Near the west line of the 

 town, on the first road north of Island pond, we find the same materials 



