GEOLOGY OF THE WHITE MOUNTAIN DISTRICT. I5I 



and the high ridge south. It is true, however, in regard to both these 

 mountains, that the rock of their summits is composed chiefly of feld- 

 spar, with which there is associated a httlc hornblende. A similar rock 

 forms a part of the ridge extending from Passaconnaway to Chocorua. 

 North of Swift river. Silver Spring mountain, and also a mountain north 

 and one west of it, are composed of this rock. On Sv/ift river, just below 

 the falls, there is a rock very similar, except that it contains some quartz. 

 There is an outcrop also on this stream four and a half miles above 

 Albany interval. 



Comuay granite. The area of Conway granite in Albany is not large. 

 In the south-east part of the town it can be seen in several places. Near 

 the house of S. Littlefield it seems to be undergoing rapid decomposition, 

 yet there are some places where it is not much changed. At Littleficld's 

 house the granite is cut by a trap dyke, that is not far from a hundred 

 feet in width. Three miles south of Swift river, towards Birch interval, 

 there is a typical granite, rather coarse, but the feldspar, which is of a 

 light color, is not stained by iron or coated by manganese. The first 

 outcrop of granite south of the house of N. Shackford is somewhat por- 

 phyritic, and the crystals of feldspar are often very large. This is sug- 

 gestive of the ancient porphyritic gneiss. The rock of Green's cliff and 

 its ridges has all the constituents of common granite, but they are so 

 distinctly crystallized that it very readily crumbles and falls in pieces. 

 Up Downs brook for two miles and a half granite is the only rock, except 

 a trap dyke that cuts it. In Waterville, on Sabba Day brook, there is 

 common granite at the falls and a mile above. j. h. h. 



The Granites in Conway and the Southern Border of the 

 District. 



There are many outcrops of the lower granite along the edge of Con- 

 way and Bartlett, in the neighborhood of Kiarsarge village. They are 

 well shown in the Artist's Falls stream, up towards Pequawket and the 

 Green hills. We find both these granites under Mt. Pequawket on every 

 side. On the east, west, and south there are specimens illustrating them 

 on Section VIII, and they have also been found on the north. The 

 Albany granite is not more than two or three hundred feet thick, but it 

 seems to form a sheet extending horizontally through the mountain be- 

 neath 2000 feet of later rocks. The relations of the underlying Conway 



