474 STRATIGRAPHICAL GEOLOGY. 



Connecticut valley, has been already described, so we shall notice only 

 that which is found east of the main range of the quartzite. 



The lithological characteristics of the northern variety of the proto- 

 gene or Bethlehem gneiss have been pointed out so often that it will not 

 be necessary to repeat them here. When this rock occurs east of the 

 quartzite, it is not always easy to tell where it ends and where the com- 

 mon gneiss begins. A characteristic variety of the Bethlehem gneiss 

 is found in Hanover and Canaan, to the east of Moose mountain ; and a 

 fine-grained variety extends northerly into Lyme. The whole forms an 

 oblong area, the northern limit being near the saw-mill north of the old 

 Holt tavern, and its southern, near the village of Enfield. On the south 

 it is compact, rather thick-bedded, contains quite a large proportion of 

 flesh-colored feldspar, and it is quarried in the north-east corner of Han- 

 over and in the south-west corner of Canaan. Northward, especially in 

 Lyme, it becomes quite friable and crumbles easily, and it is separated 

 from the protogene area westward by a band of quartzite. The water- 

 shed between the Mascomy river and Goose Pond brook is probably 

 the limit of this area eastward in Canaan. Other areas of the protogene 

 gneiss that occur along the north-west border of the common gneiss, that 

 have not already been described, will be noticed with the common gneiss. 



In Grantham, west of Croydon branch, we find a reddish protogene 

 gneiss that is quite different from the protogene gneiss northward ; it is 

 much finer-grained, is cut by numerous joints, and in it here and south- 

 ward there are intrusive bands of quartz. It extends from the road north 

 of D. S. Hastings's southward to the road running north-west from Croy- 

 don east village. The principal band, however, of this rock begins in 

 Surry, across the ravine south of George Joslyn's, and extends through 

 the edge of Keene and Westmoreland into Chesterfield to the forks of 

 the road south of J. Putnam's. The first prominent outcrop is south-east 

 of G. Grain's : at first there are few quartz veins ; then south the rock 

 seems to be almost entirely quartz; but west of C. Wright's we have 

 ledges of protogene ; and cast of school-house No. 4 we find in basins 

 of this rock the mica schist which is so common to the north-west. 

 The reddish gneiss, — for the protogene character of the rock is not 

 always apparent, — is cut by the railroad in the south-west corner of Surry, 

 and below, at the first crossing in Kcenc. In the latter cut we find, going 



