114 STRATIGRAPinCAL GEOLOGY. 



be derived from these facts is, that a powerful pressure has been exerted 

 upon these strata, which has doubled and twisted all the layers in detail, 

 not in the mass like the representations of the Appalachian curvatures 

 by the Professors Rogers. Observations upon Adams, Jefferson, and 

 Washington show the same thing to be true there also, so that this con- 

 clusion will apply equally forcibly to the whole range. The extent of the 

 reduplications exceeds anything that I have ever seen in any part of the 

 world. 



In descending from this ridge to H. D, Copp's house, in Martin's 

 Grant, the most noticeable feature is the introduction of large crystals 

 of staurolite into the rock. Andalusite had been abundant all the way 

 from the summit of Madison ; but at about three hundred feet below the 

 tree line, in an open space, the staurolite has striped the ledges in every 

 direction. The crystals run up to eighteen inches in length; and I 

 think there is scarcely any place in the state where large and showy 

 specimens of this mineral can be obtained more easily, only that they 

 cannot be conveniently transported. It is unusual to find this mineral so 

 abundant among the mountains. Lower down, the crystals are smaller 

 and very distinct, the strata dipping 75° W., and very shortly falling to 

 an average of 28°, continuing thus for a great distance. About three 

 fourths of a mile above Copp's the same staurolite rock dips 50° S. 

 53° W. The granitic gneiss makes its appearance a little below Copp's. 



The general surface features of the path up the north side of Mt. 

 Adams, and the route from Madison to Washington over the ridge, are 

 set forth under the head of Scenographical Geology, Vol. I, p. 613, ct 

 scq. Mt. Adams has three summits instead of two, as heretofore stated. 

 The more southern one is properly the Ouincy Adams, and there is also 

 a small peak between the central peak and the Madison notch. The 

 summit of Adams is very sharp, there being only one small block of 

 stone at the apex. Ridges extend down the north side of the mountain, 

 starting from the two lesser peaks. None of our parties have traversed 

 the north side of Adams, Madison, or Jefferson, so that we cannot de- 

 scribe the ledges there. On the summits and in the notches between 

 them the rock is invariably the feldspathic andalusite mica schist, with 

 the blotchy mica. On Ouincy Adams the strata dip N. 20° W. Near 

 the Jefferson- Adams notch the dip is 50° east. Still farther south the 

 dip is N. 62'' W. 



