394 TRANSACTIONS OF SECTION C. 



The central or Rowley ridge is sagged at three equidistant (4 miles) places, 

 (a) near Halesowen, (6) S.S.E. of Dudley, and (c) N.N.W. of Sedgley, and at 

 these places it is crossed by three Caledonian trend-lines with a general S.S.W.- 

 N.N.E., direction. The middle one of these trend-lines connects up the anti- 

 clinal arete of Netherton, the synclinal ravine of Tividale, and the Walsall 

 plateau, each of these elements being four miles long. The north-western 

 consists of the Himley to Sedgley Park arete (4 miles), beyond which it sinks 

 into a shallow sync-line (3 miles), and rises again, near to and beyond Essington, 

 into a narrow arete. The south-eastern one forms an arete, not shown on the 

 model, from near Hagley in the direction of Halesowen, which sinks into a 

 long and broad synclinal ravine towards and far beyond Halesowen (5 miles), 

 and then becomes a well-developed anticlinal arete from Spon Lane to beyond 

 Great Barr. The Central Caledonian trend-line therefore divides the two 

 synclines on the opposite sides of the central Charnian ridge, each into two 

 parts, that to the W.S.W. being divided by a sharp anticlinal arete, and that 

 to the E.N.E. by a narrow and deep synclinal ravine. 



The Central Charnian and Caledonian trend-lines form an X. 



The evidence, derived from over fifty pits sunk into, and the outcrops of, 

 the Pre-Carboniferous rocks, shows that movement in both Charnian and Cale- 

 donian directions, accompanied by and followed by faulting and denudation, 

 had taken place in the district previous to middle coal-measure time, and that 

 this denudation, was greatest at the S.S.E. ends of the Charnian anticlines, and 

 less on the Caledonian anticlines. 



The Central Charnian ridge, from Sedgley to south of Blackheath, combined 

 with the east to west faults of the Tipton and Cradley synclines, closely 

 approach to the form of the letter S. The throw of the most important of 

 these faults is in the Tipton syncline to the south,' and in the Cradley syncline 

 to the north. They invariably die out to the east in both these synclines, 

 against the S.S.E. ends at Blackheath and Walsall, of the more denuded parts 

 of the Charnian ridges, whilst they succeed to the west, with greatly diminished 

 throws, in breaking through and laterally shifting the N.N.W. end of the 

 Charnian and the S.S.W. end of the Caledonian ridges at Sedgley and Lye, 

 which had been elevated much less by these two older movements. 



The Central Caledonian trend-line, comprising, as the middle limb, the anti- 

 clinal arete of Netherton and the synclinal ravine of Tividale, if combined with 

 the Langley N.-S. and the Stourbri'dge-Kingswinford S.S.E.-N.N.W. aretes also 

 forms the letter S. 



The plexography of South Staffordshire is markedly reflected in the 

 physiography. 



A plexographic map of the South Wales syncline made by some person who 

 could collect information therefor, before the Cardiff meeting, should materially 

 increase our knowledge. 



4. Underground Contours of the Black Mine. By Dr. G. Hickling. 



5. Underground Contours of the Barnsley Thick Coal. 

 By Professor W. G. Fearnsides. 



Joint Meeting with Section K. — See p. 493. 



i^ Compare Jukes' Mernoir, 2nd e,d., p. 165,. 



