122 DR. en. CALLAWAY ON THE UNCONFORMITIES BETWEEN 



strike to the east at a distance of nearly a quarter of a mile. Also 

 the felspar-porphjry of Hope Bowdler runs E. and W. for about 

 half a mile. 



Besides calling attention to the occurrence of structural strikes, it 

 is of importance to point out the trend of large masses. Thus, the 

 rhyolite in the Woodgate glen appears to strike almost E. and W. 

 across the two ravines to the west, and to be produced less distinctly 

 in the opposite direction to Stone Acton, so that it is probably con- 

 tinuous from end to end of the Cardington massif. Also the strike 

 of the grit in the glen opposite *' The Yells " is in a line connecting 

 masses of grit at Gaer Stone with others in the Woodgate ravine, 

 and this line is parallel to the strike of the adjacent rhyolite. On 

 the other hand, I have not observed that any bedded or banded rock 

 in this district trends in a direction transverse to the prevailing 

 strikes. 



Summarizing the details of all the districts, we notice that the 

 strikes in the Wrekin area are usually either E. and W. or E.N.E. 

 and "W.S.W.; in the southern area, they are E. and W. or some point 

 between W. and N.W. The only strikes in the Uriconian which lie 

 parallel to the normal Longmyndian strike are those near Wrock- 

 wardine, at the northern end of Hazier Hill, and on Little Caradoc 

 and the last-named is really a little to the west of north. The bands 

 in Caer Caradoc and Eagleth which trend to the north can hardly 

 be reckoned, for they curve round at each end, and abut on the fault 

 at nearly a right angle to the Longmyndian strike. It will be 

 observed that all the Longmyndian strikes in Uriconian rocks are 

 near the fault. Also that, in such important masses as Charlton 

 Hill and Caer Caradoc, the transverse Uriconian strike comes close 

 up to the fault. It is hardly rash to assume that the strikes at a 

 distance from the great fault are least likely to have been disturbed, 

 and are therefore most reliable as indications of the original lie of 

 the rocks. 



2. The Faulted Junction. 



The two formations come into visible contact along a line of onlv 

 about 2| miles. The fault drawn on the Survey map runs in a 

 straight line from the western margin of Caer Caradoc to Little 

 Stretton, throwing down Silurian (Wenlock) rocks against Ordo- 

 vician and older systems. The area east of the fault is marked 

 " b^" (Caradoc) on the map, but it is correctly recognized by Prof. 

 Blake as Longmyndian. It is this mass which abuts upon the 

 volcanic series. The contact is certainly a fault at the northern 

 ond, near Caradoc Coppice. The dislocation can be taken up again 

 about a mile to the south, near the cluster of cottages called 

 Hazier. An interesting section of the junction-rocks is seen on the 

 old road up from Church Stretton to this locality. The ordinarv 

 green slates of the Longmyndian crop out at intervals up the road 

 tor nearly half a mile, with the normal strike to JS'.N.E. As we 

 approach the hamlet, the slate loses its lamination, and, near a well, 

 it comes to an abrupt end. At this point it has a burnt appearance, 



