GEOLOGY OF THE MERRIMACK DISTRICT. 473 



along the side of Moosilauke, far up its western slope, through Warren 

 along the steep slope of Mt. Carr, and extending south it crosses the line 

 between Wentworth and Rumney near its southern terminus; then it fol- 

 lows near the line of Dorchester and Groton, then runs just east of the 

 west line of Canaan, thence southward, near the west line of Grafton. 

 In Springfield it is not so well defined, but is probably about a mile west 

 of the old Sulloway tavern. In Sunapee it is not far from Union church, 

 on the road from Sunapee Harbor to Newport. In Goshen it runs nearly 

 parallel with the road that goes south through the east part of the town, — 

 generally a little to the east of this road. From Goshen it turns west- 

 ward, and runs south along the west slope of Lempster mountain, thence 

 south-east nearly to East Alstead. Though the boundary is not well 

 marked through Alstead, yet in Surry it is again well defined. South- 

 ward, the boundary becomes more indistinct again ; and the rock on the 

 east verges into the micaceous and granitic gneisses of the White Moun- 

 tain series, and the line turns somewhat to the east, running almost 

 directly to South Keene ; thence southward, and crosses the Cheshire 

 railroad just above Marlborough depot, when it goes south near the line of 

 Swanzey and Troy. After it reaches Richmond, it turns suddenly to the 

 south-west, and strikes the line of Richmond and Winchester a mile and 

 a half north of the state Hne, and leaves a small area of White Mountain 

 gneiss in the south-east part of Winchester. Between this line through 

 Richmond and the porphyritic gneiss in Winchester, we have for the 

 most part the Bethlehem or protogene gneiss, though it differs from the 

 gneiss in the northern part of the area we have described. We find also 

 several areas of protogene, which are contemporaneous with or older than 

 the common gneiss. 



Protogene Gneiss. This is found along the western border of the com- 

 mon gneiss in Haverhill and some of the towns south. It is quite unlike 

 that found in Grantham, Keene, and some of the adjoining towns. In 

 the latter the feldspar is often flesh-colored, and sometimes it largely 

 predominates. We find elsewhere a large proportion of quartz ; then we 

 have a greenish mineral, probably chlorite, — certainly not mica. If the 

 chlorite is wanting, mica, when present, is in minute scales, and collected 

 in patches through the rock. The protogene gneiss, known as the Beth- 

 lehem gneiss of the northern part of the topographical district of the 

 VOL. II. 60 



