Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/835

 which forms the summit of Wallow Crag and Falcon Crag corresponds to that which succeeds the great slate-band of Honister, in Seatoller Fell. 4. The slates and breccias which occur in the lower part of the Watendlath valley, and again at Watendlath village, are undoubtedly the equivalents of the Borrowdale Slates. At Watendlath village this band appears to be shifted considerably to the south, since it can be traced across the southern end of Brund Fell nearly as far as Rosthwaite, in Borrowdale ; and the prolongation of this line of strike would carry it out to Seatoller, whereas the slates on the western side of Borrowdale do not extend further to the south than Castle Crag, about a mile to the north of Seatoller.

Fig. 2. — Section from Keswick to Watendlath. Distance four miles. Watendlath.

a. Skiddaw Slates. b. Lowest trap of the Green-slate series. c. Ashes, breccias, and amygdaloids, with some trappean beds. d. Second trap of the Green-slate series.

III. Lower portion of the Green-slate Series between Keswick and the Vale of St. John.

Crossing the north and south ridge which divides the depression in which Derwentwater is situated from the parallel valley of Naddle Beck, the base of the Green-slate series is seen close to the farm of Rake Foot in the form of a greenish grey felspathic trap, which is continuous to the west with the trap of Castle Head, and is traceable eastwards into the valley of Waddle Beck. Here, close to a farm called Dale-bottom, it is seen resting upon the Skiddaw Slates in the course of a small stream which flows down from a hill known as the Pike. In both places this lowest trap is overlain by a series of red and green breccias, which, however, are of considerably less thickness than further to the west in Wallow Crag. Intercalated in these breccias in the Pike is a large mass of felspathic trap, sometimes porphyritic ; and this is succeeded by an exceedingly fine amygdaloid, the cavities of which are sometimes of very large size, and are filled either with calc-spar or with agatescent quartz. The strata which form the Pike are, thus, essentially the same as those which occur in Wallow Crag; but the breccias have to a great extent thinned out in their passage eastwards.

Southwards, the strata which form the Pike are succeeded by a great series of bedded traps with a few ashy beds, the former greatly