File:The Quarterly journal of the Geological Society of London (12645822643).jpg

1862..
HARKNESS SKTDDAW SLATE SERIES.
127
of a lighter colour, which are again succeeded by dark shales resem-
bling those below, and containing Graptolites. Drab shales are seen
above these in the course of the brook, having intercalated grey
beds, the whole presenting a shivery aspect.
Above the foregoing shaly strata, for a short distance no rocks
are seen in the bed of the stream ; but a little above where the main
road from Barton to Martindale crosses Eggbeck, a greenish-grey
porphyry, with orange -coloured crystals of felspar, makes its ap-
pearance, and continues to occupy the bed of the stream to near its
source, having occasionally ashy masses intermixed with it.
The Graptolites which occur in the dark shales of Eggbeck con-
sist of Graptolites Sagittarius and Didymograpsus geminus, together
with the branching form previously referred to. These fossils are
by no means abundant here, and, owing to the shivery nature of the
strata, they are usually in a fragmentary condition.
Eig. 4.-
N.N.W.
-Section from Ullswater to Wastdale Crag (11 miles).
S.S.E.
Skiddaw Slates.
Green slates,
porphyries, &c.
Skiddaw Green a
Slates. slates, &c.
a. Trap. b. Syenite.
Lying west from Eggbeck is Barton-fell. At the top of this hill
is a greenish, ashy-looking grit ; and in the stream which separates
Barton-fell from Swarth-fell, the hill still further westwards, the
porphyries of Eggbeck are well seen, together with greenish rocks,
which are not porphyritic, intercalated among them, but having no
distinct bedding. The rocks here are rudely prismatic, and to the
S.S.E. they seem to pass upwards into the greenish-grey rock above
alluded to.
Eggbeck is the only spot in this neighbourhood where the Skid-
daw slates are seen. To the north of Barton-fell and Swarth-fell,
both of which rise boldly above Ullswater, exhibiting escarpments
on their north sides, there is a comparatively low tract of country ;
but there no rocks in situ appear, the interspace from the south side
of Ullswater to the adjoining hills being covered by soil and debris.
The contour of the country, however, justifies the conclusion that
the Skiddaw slates extend some distance along the northern base
of Barton-fell and Swarth-fell, but that they soon become covered
up by the porphyries, ash-beds, and green slates, which are so ex-
tensively developed along the margin of Ullswater, from Howtown to