124 STRATIGRAPIIICAL GEOLOGY. 



large veins of granite, whicli are very common here. I tliink the usual 

 granite on the west side of Mt. Webster is the variety to be described 

 as the "Conway;" but my notes speak of the recurrence of the hard 

 siliceous granite of Silver cascade, east of the Saco river, and that it 

 extends as far as the first bridge over the river below the Willey house. 

 The schists do not extend to the south end of the Webster range, their 

 jolace being taken by the granite which occurs upon Mt. Washington 

 river, about as far north as the latitude of the Willey house. 



Mt. Deception range. There remains to be noticed a triangular area 

 to the north-west of Ammonoosuc, or the eastern part of the Cherry 

 Mountain district, consisting of Mts. Mitten, Dartmouth, and Deception, 

 with their northern slope to Israel's river. Mt. Mitten is composed of 

 the same coarse feldspathic mica schist as Mts. Adams and Jefferson. 

 It is the first of the east and west range branching from Mt. Jefferson. 

 Mt. Dartmouth is composed of a granite, with small porphyritic crystals. 

 Mt. Deception is built up of a coarse Concord granite. Between this 

 ridge and Israel's river there is a long slope ; and nothing is known of 

 the ledges there. Along the river the rocks are concealed by thick piles 

 of earth; and the poor prospect of finding much solid rock there has 

 always debarred the most ambitious of our parties from making the 

 attempt. The western part of the area is obviously the boundary be- 

 tween the Bethlehem and Montalban groups ; and it is not likely that 

 any of the granites extend very far in a northerly direction. Very near 

 the north-west corner of Lowe & Burbank's Grant there is a corrugated 

 mica schist, abounding in mica, dij^ping 85° S. 23° E. 



Concerning another extensive area our information is also meagre. It 

 is of the mountains south of Tuckerman's ravine, on the west side of 

 Ellis river as far as Iron mountain in Bartlctt. The rock is believed to 

 belong to the same system of Montalban schists that we have been de- 

 scribing. It was through the heart of this region that the exploring 

 party of Dr. Cutler made its way in 1784. We have, however, important 

 facts to state concerning the district of Mt. Washington river. It has 

 been explored three different times. 



Mt. WasJiington river. This is the longer branch of the Saco above 

 Bemis station, but it is reckoned as a tributary rather than the main 

 stream. We have not visited its very source, close by the Lakes of the 



