620 STRATIGRAPHICAL GEOLOGY. 



depot, coming up in connection with a very coarse granite. The princi- 

 pal range rises to Flint hill, in the north part of the town, then falls oppo- 

 site the Pawtuckaway river, and rises to view with a north-west dip at 

 several places in Nottingham. In Lee, near M. Thompson's, is an un- 

 usual display of similar boulders, as if their source could not be far dis- 

 tant. There are ledges of this rock in the other area in Northwood, 

 on the east side of Pleasant pond, with a northerly course. It does not 

 yet show itself to the east of the main anticlinal. The bands observed 

 must belong to a later formation than the typical ranges in Hillsborough 

 county. 



The granitic masses are unusually large in Danville, being more than a 

 mile wide east of Wm. Bagley's. In the area lying partly in Danville and 

 partly in Kingston, between Long and Half-moon ponds, the granite con- 

 stitutes something of a hill. The granites of this group are mostly want- 

 ing in Fremont, Brentwood, and Epping. The same is true of the south 

 part of Nottingham, Lee, and Madbury. In Somersworth there is a large 

 granitic area, in the north part of the town, possibly of eruptive character. 

 In Dover, at Sawyer's mills, the schists are well exposed in a railroad ex- 

 cavation, and bear marks of strong pressure, with many small slickensides. 



The Rockingham group in Hillsborough county is characterized by 

 orographical features, as exemplified by the presence of a mountain range 

 commencing with Kidder and Temple, continued in Pack Monadnock 

 and the Lyndeborough hills, and preserved farther north-east in the soli- 

 tary pile of the Uncanoonucs. The Merrimack valley brings up the older 

 gneisses, and as soon as we pass a few miles to the north-east this ele- 

 vated range reappears very prominently in the four mountains of Epsom, 

 — Brush hill, McKoy's, Fort, and Nottingham mountains, — Catamount 

 in Pittsfield, and then there is a range just a little farther to the south- 

 east, consisting of the Blue Hills range in Strafford, Blue Job, Nubble, 

 Hussey, and Chesley mountains in Farmington, and Teneriffe in Milton, 

 These disconnected portions of a once continuous range suggest eleva- 

 tions of the underlying formations along what are now valleys of denuda- 

 tion, and the subsequent wearing away of the mountains of mica schist 

 now needed to fill up the gaps in the range. 



