88 STRATIGRAPIIICAL GEOLOGY. 



Diamond, from where the stream flows into the Dead Diamond, about 

 a mile above the Narrows, forms a deep, irregular basin towards Mt. 

 Pisgah and the water-shed between the Magalloway and the Connect- 

 icut. The hydro-mica schist forms a monoclinal axis, and has every- 

 where a westerly dip, though nearly vertical. In the basin of the Little 

 Dead Diamond the rock is sometimes quite argillaceous, but, approaching 

 the water-shed, it seems to pass into a gray siliceous schist. On the west 

 side of the water-shed, on the head waters of Cedar stream, there is a 

 band of clay slate perhaps a quarter of a mile in width. It has generally 

 an easterly dip, at a high angle. Following this is an arenaceous schist 

 that extends to Clarksville, but interstratified with it is a band of quart- 

 ziteand three bands of diorite. All these rocks have an easterly dip. In 

 Clarksville, also extending into Canaan, Vt., there is a series of calcareo- 

 argillaceous rocks, consisting of several folds. In the cast part of Clarks- 

 ville the rocks are both argillaceous and micaceous, and frequently they 

 contain lime as an incrustation. In the north part of Clarksville, particu- 

 larly in the vicinity of the bridge across the Connecticut, the rocks are 

 mainly micaceous. At Hall's stream there is a wrinkled and corrugated 

 argillaceous schist. This is followed by a calciferous mica schist; and 

 on the Connecticut river at Canaan there is a band of siliceous lime- 

 stone. West of Canaan village the rocks consist of micaceous schist; 

 probably for the most part they are calciferous mica schist. At Great 

 Averill pond there seems to be a granitoid gneiss; and westward, to 

 the first road in Holland, all the outcrops of rock are granite. Then 

 follows a calciferous mica schist. 



Section XII. 



Section XII extends from Umbagog lake directly west, and strikes the 

 Connecticut river half a mile north of Lyman brook in Columbia, and 

 extends west to a point about two miles south of East Charlestown. Be- 

 tween these points the country for the most part is covered by forests, 

 and is broken by mountain ridges and cut by deep ravines. The towns 

 traversed in measuring the section were Errol, Millsfield, Odell, and 

 Columbia, in New Hampshire, and Bloomficld, Brunswick, Ferdinand, 

 Brighton, and Charlestown, Vt. Umbagog lake is 1256 feet above the 

 sea level ; and on its eastern shore we find a dark-colored granite, pecu- 



