GEOLOGY OF THE CONNECTICUT VALLEY DISTRICT. 335 



hill, and terminates a short distance north of North Lisbon, reaching 

 the gneiss. At the beginning is the Lyman instead of the Lisbon group, 

 though the latter would appear if the section had been elongated half a 

 mile. Near G. D. Shute's house and "Indian Rock" these schists dip 

 85° N. 30° W. The east border of this group dips 80° N. 40° W. It 

 weathers whitish, presenting a chalky aspect at a little distance. Along 

 th'e carriage-road succeeding is an extensive range of Helderberg slates 

 and limestones, containing Favositcs. The strata stand perpendicular, 

 running north-east. On a tributary stream, near C. Hastings's house, is 

 a fine exposure of grit, slates, and calcareous beds, greatly resembling 

 fossiliferous strata in Maine and New York, but they yielded no relics 

 of life, in a half-hour's search. This series of strata forms a steep cliff 

 seventy or eighty feet high, which can be followed a mile and a half to 

 the slate quarry. The country at the base of the cliff is everywhere a 

 swampy forest not intersected by roads, so that its exploration is not 

 inviting. 



Passing up the hill there are so many boulders of conglomerate, that 

 we must believe this to be the rock in place. Near a school-house it dips 

 S. 6?)° E. Its character does not vary from that seen in Fig. 42. This 

 view will make the fossiliferous slates correspond with the slates at the 

 quarry. Near the top of Blueberry hill are slates with the course N. 55° 

 E.; and others dip 20° south-westerly, which may be explained by sup- 

 posing cleavage planes to be present having a different strike from the 

 strata, or by a local sliding. On the crest of the hill the slates dip 70° 

 N. 35° W. This continues about half a mile on the line of section, or 

 as far as I was able to travel upon it. There is room enough for the 

 double thickness of slate seen in Fig. 42. 



The slates extend on the eastern slope of the hill to the ridge east of 

 C. Ela's in Lisbon, where there is an excavation in them made for some 

 mining object. The greenish Huronian schists adjoin them, followed by 

 a hornblendic band, seen at J. Clark's, dipping north-westerly. Speci- 

 mens of the mica schist come next, probably the whetstone slate layer, 

 followed by more hornblende and the Swift Water sandstone, a rock with 

 whitish cement and pebbles of the size of buckshot, with vertical dip. 

 The locality of the last is on top of the hill, next the Ammonoosuc river. 

 The hornblende first spoken of is that connecting the Whipple Brook 



