STRUCTURE OF THE MOUNT WASHINGTON MASS. 729 



suggested by topography. The series of sections in Figure 2 

 will show this in some measure.- 



Beginning with Mt. Everett, we find that it presents a uni- 

 formly steep eastern slope of Everett Schist, the limestone being 

 in contact near the Undermountain Road. Where the slope of 

 Mt. Race begins a little farther south, an abrupt recession occurs 

 in the face of the range, which extends west to the foot of steep 

 cliffs and south to the road north of Sage's Ravine. Into and 



Fig. 2. Series of sections from the east flank of Mt. Washington, showing how the 

 limestone of the valley gains the summit plain. 



along this "bench" runs the Egremont Limestone. Proceeding 

 southward from the north end of this "bench," a tongue of schist 

 is met lying within the limestone, about midway between the 

 cliffs and the road, and forming a backbone, the slope immedi- 

 ately west being very gradual while that to the east is tolerably 

 steep. This tongue of schist broadens to the southward, narrow- 

 ing that belt of limestone which lies to the west of it. As this 

 limestone belt becomes narrowed toward the south, it ascends the 

 mountain, losing as it does so most of its calcite and developing 

 into a black graphitic schist. This reaches the altitude of the 

 summit plain about one-eighth of a mile north of Bear Rock 



