MUSEUM OF COMPARATIVE ZOOLOGY, 213 



preservation to the circumstance that the modified red granite wliich 

 makes it up divides in weathering into plates, which, when undisturbed, 

 stand vertically on edge. They vary in thickness from an inch, or less, 

 to upwards of a foot. Where their trend is in the same direction as tiie 

 ridge, there, as they have become loosened, and have fallen over the 

 cliffs on either side, the plates still left firm in place constitute a nar- 

 row crest. It is surmounted by a serrated edge, and, as one follows it 

 for the fourth of a mile, alternately ascending steep projecting points, 

 and descending into jagged notches between, he must again and again 

 walk along a mere blade of rock from one to two feet wide, having upon 

 one side the yawning gulf of the basin, and on the other cliffs too steep 

 for climbing. 



From the crest southwest to East Peak, and between that and "West 

 Peak, the rock plates stand crosswise of the ridge at various angles, and 

 there, as they have been loosened by frost, falling more or less out 

 of perpendicular, they still remain. Thus the blade-like form is lost, 

 and the ridge is somewhat wider, though still narrow. Bristling with 

 oblique, projecting plates covered with black lichens, these parts pre- 

 sent a savage and chaotic desolation that is probably without a parallel 

 in Eastern North America. 



The very diverse conditions of surface upon the other summits — 

 hardly their forms — may be traced sometimes to variations in the 

 jointing of the constituent rock, but oftener to simple difference in firm- 

 nags. Thus, parts made up of the more friable red granite (other than 

 those modifications of it, represented by specimens 23, 25, and 57, that 

 divide into thin plates, and are confined to the highest summits only) 

 are covered with small-sized fragments, rounded by decay. These at 

 times assume, over wide spaces, the size, and almost the arrangement, 

 of cobble paving-stones, and in a few places the aspect of gi-avelled 

 areas. Such are seen chiefly on the northern summits. 



Again, the middle of the northward slope, between the Table Land 

 and the Saddle, is piled with blocks of the firmer red granite, riven 

 from the mass beneath, of size so great as to render travel over them 

 extremely difficult. The Table Land is in parts smoothed by a covering 

 of wholly disintegrated material, but in general is strewn with tabular 

 blocks that increase upwards toward West Peak in size and number. 

 The half-mile between the head of the great Southwest Slide and the 

 brow above is literally a heap of huge blocks, constituting a slope that 

 varies from 36° below to 47° above. 



The slopes south from the two chief peaks are covered with loose, 



