GEOLOGY OF THE MERRIMACK DISTRICT. 535 



gneiss across to the north-east point of the same kind of rock west of 

 Bear pond. There are probably two similar axial lines in Salisbury. 



Little is known of the area put down for Amy brook, Henniker, and 

 extending into the edge of Warner. It may possibly belong to the ferru- 

 ginous schist deposit. The rock is like the siliceous layers occasionally 

 associated with the porphyritic gneiss. 



The Bradford pond area distinctly belongs to this Lake formation. It 

 extends into Warner, where the stone has been quarried, as it splits read- 

 ily into long slabs suitable for underpinning and pillars. It is believed to 

 dip north-west at its east border by Day pond. It crops out along the 

 west side of Bradford pond. The rock also occurs in enormous boulders 

 over this area, and the dips are obscure. At the outlet of the pond the 

 dip is 50° N. 26° W. 



The Hillsborough area may commence two or three miles below the 

 bridge, the land being free from ledges in the valley. The village at the 

 end of the railroad occupies a ridge of glacial drift that has been thrown 

 across the valley in ancient times, producing a lake which by filling up 

 gave rise to the long flat meadow land above. The ledges at the upper 

 dam consist of gneiss and coarse granite, dipping N. 40° W, On the east 

 side of the river a rough gneiss dips 80° N. 80° W. 



About two miles into Deering, by H. Preston's, is a small ledge of a 

 hard variety of the Lake gneiss, which constitutes the eastern limit of the 

 formation. On the line of Section III, about three miles from the bridge 

 in Deering, is a gneiss of similar character. The dip is uncertain. It 

 should be westerly if like the same strata farther north, but easterly if it 

 agrees with the schists overlying it. The latter is the probable dip, thus 

 giving us an anticlinal axis in the Contoocook valley. The rock is sup- 

 posed to extend south-westerly to pass into the known outcrops of similar 

 rock between Antrim centre and Clinton village. Just south of the latter 

 hamlet the rock is a hard, dark-colored, crystalline gneiss, such as is charac- 

 teristic of the Lake group farther north. This Hillsborough area is very 

 much like the well-defined one already noticed in Bradford, only larger, 

 being nine and a half miles in length instead of three and three quarters, 



I think it well to regard the three isolated patches in Francestown, 

 Deering, and North Weare as continuous, constituting a range ten miles 

 long. On the north-east the gneiss has been observed in a precipitous 



