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GEORGE W. STOSE 



peneplain, whereas the intervening portions of the ridge are reduced 

 to a sharp crest. 



To the west is a group of ridges striking entirely across the area 

 and forming the main mass of this western range. At the north the 

 structure is complex and the ridges are irregular. To the south the 

 mountain is composed of two distinct monoclinal ridges, with a deep, 

 broad, synclinal valley between. The eastern limb, forming Cove 

 Mountain, is vertical, and has been weakened by faulting, so that 

 the summit is a knife-edged crest of jagged quartzite beds. Although 



Fig. 2.— North Mountain from the plateau west of Charabersburg. 



some of its highest points reach i,8oo feet, its average height is between 

 1, 600 and 1,700 feet, and its crest has a decided wavy or comby appear- 

 ance. Just beyond the southern border of the quadrangle this ridge 

 swings to the east, across the end of a fiat antichne, in what is known 

 as Cross Mountain, and then extends northward again a short dis- 

 tance as Two Top Mountain. From the valley one observes an 

 abrupt change from the low, comby crest of Cove Mountain to the 

 uniform, level crest of Cross Mountain (see Fig. 3) which has an 

 altitude of about 2,000 feet. It is apparent that Cove Mountain 

 once stood at approximately this altitude, but has been lowered by 

 the active erosion of the relatively narrow exposure of upturned 

 rocks. The broad mass of gently dipping strata in the anticline of 



