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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 uniformly 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 immediately west being very gradual while that to the east is tolerably steep. This tongue of schist broadens to the southward, narrowing 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