660 C. CALLAWAY ON THE PRECAMBRIAN 
chiefly made up of pebbles of quartz, and contains flakes of silvery 
mica, apparently due to subsequent alteration, 
In the N.W. side of the hill, the fault brings down Longmynd 
strata against the Precambrian axis. The slates which rest against 
Hazler Hill are continued for about one third of the length of the 
Ragleth, when they suddenly give place to the purplish felspathic 
sandstones which lie in force to the 8.W. ‘The relations of these 
subdivisions of the Longmynd series are not yet fully known, and do 
not concern our present purpose. 
Summary.—A 8.W. ridge composed of claystones and felspathic 
grits; a W.N.W. dip, due to a greenstone protrusion on the 8.E. 
side, and a N.N.H. dip at the 8.W. end, with another greenstone 
mass a short distance to the W.; Caradoc rocks faulted against the 
S.E. side and lapping round the 8.W. end; Longmynd slates and 
sandstones faulted down on the W.N.W. 
15. Wartle-Knoll Group. 
East of the farm named Carwood is a small conical knob composed 
of brownish felstone full of closely approximated joints(Note 8, p.668). 
Wartle Knoll, a loftier elevation, is chiefly made up, especially in the 
centre, of a breccia of quartz and felsitic fragments. Felspathic 
rocks of an obscure character are found on the slopes. The Carwood 
mass is coloured as Caradoc by the Survey. Its position on the S.W. 
axis, together with its resemblance to some of the Precambrian vol- 
canic series, renders its Precambrian age almost certain. Wartle 
Knoll rises up through Longmynd strata, and is coloured as such on 
the Map; but on the whole it resembles Precambrian rather than 
Cambrian rock. 
The Precambrian axis is evidently continued under the purple 
Longmynd sandstones of Hopesay Common, and underlies an anti- 
clinal of Caradoc rocks at Corston, two miles 8.W. of Wartle 
Knoll. 
16. Aington Group. 
Hanter Hill is composed of gabbro on the E. side and dolerite at 
the summit. On its N.H. slope is a small exposure of a grey grani- 
toid rock (Note 9, p. 668). 
Stanner Rock contains similar dolerite and gabbro. In about the 
centre of the ridge is a grey compact felstone. At the N.E. end is 
a dark grey grit with obscure E. and W. bedding, and near it to the 
S. is a quartzose breccia. In the same locality is seen a greyish 
granitoid rock, similar to the specimen at Hanter Hill. The struc- 
ture of this ridge suggests that of the Lawley. 
I refer this group with hesitation to the Precambrian period. The 
rocks are brought up on the same axis of upheaval, but the litholo- 
gical resemblances are not at present very decisive. The greenstones 
are, of course, eruptive and posterior. 
