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Home , Forest of Dean, May Hill, Taff Vale Railway

,142 F. W. RUDLER ON THE COAL-FIELD.

probability, that the change may have been brought about by II gradual rise of temperature towards the north-west, connected with the thickening of the strata in that direction. He assumes that originally the coal-seams in the north-west of the field were covered by a much greater thickness of beds than in the south-east, and being thus buried deeper beneath the surface they must have been exposed to a higher temperature, which would tend to induce more or less complete de-bituminization of the coal.

EXOURSION TO THE , , AND SOUTH WALES. MONDAY, AUGUST 6TH, TO SATURDAY, AUGUST 11TH. Directors: THE PRESIDENT; WILLIAM GALLOWAY, of Oardiff; W. F. GWINNELL, F.RMet. S.; J. STORRIE, Ourator of the Museum; T. H. THOMAS, RO.A., President of the Cardiff Naturalists' Society; DR. O. T. V ACHELL, of Cardiff ; and E. WETHERED, F.G.S., F.O.S., F.RM.S., Hon. Sec. Ootteswold Naturalists' Field Olub and Nat. Hist. Soc.

(Report by 'l'HE DIRECTORS.) Monday.- had been chosen as a convenient centre for the work to be undertaken on Monday and Tuesday, and here the party was met, early on Monday morning, by Mr. Wethered, who acted as Director during the day. From Gloucester the train was taken, on the Ross and line, to Road, at the extreme north-eastern corner of the Forest of Dean. A move was at once made in the direction of Baily Hill, and on the way thither an exposure of Old Red Conglomerate was seen. The Director here called a halt for the purpose of explaining the structure of the surrounding country. He pointed out the features of the Old Red Oonglomerate, which, he remarked, pointed to an alteration of the conditions which had allowed of the deposition of the beneath, and to a coming change which brought in the Oarboni­ ferous rocks. For this reason he asked them to mark well t.his Oonglomerate, as he regarded it as the upper limit of the Old Red and Devonian rocks of the west of England. The beds which intervened between it and the true strata were, in his opinion, transitional, and should be so regarded. EXCURSION TO THE FOREST OF DEAN. 54;)

Some old Roman workings for ore were then visited, which had been excavated in the . Baily Hill Quarry was the next place of interest in the pro­ gramme. It is opened in the Carboniferous Limestone, which appears to be all dolomitized. Proceeding further, across the dip of the strata, the Lower Limestone Shales were seen in two quarries. The Director described the features of the beds and also the chief fossils which occur in them. The" deep cutting" on the road from to Ross was then visited. Here the 'I'ransition Beds, i.e., those between the Old Red Conglomerate and Lower Limestone Shales, are very well exposed. There is certainly no better exposure in the west of England. The many-coloured sandy beds and green shales which constitute this series were traced from the Lower Limestone Shales to the Old Red Conglomerate. After luncheon at a wayside inn, another quarry opening in the dolomitized Carboniferous Limestone was visited, and then some exposures of the Upper Limestone Series were examined. In these the" Crease" and "Whitehead" Limestones were shown, and resting on the latter in the Morse railway-cutting at Drybrook came the Millstone Grit. Leaving Drybrook, the party turned in the direction of Mitcheldean, where the Wilderness Cement Works Were to be visited. On the way some further beds of Millstone Grit were pointed out. They were of special interest inasmuch as they greatly resembled the Old Red Conglomerate in lithological structure, containing" veinstone" quartz pebbles which could not be distinguished from those in the Old Red Conglomerate. Mr. Colchester-Wemyss now took the lead, and conducted the geologists to the Wilderness Cement Works, Limited, of which he is the Chairman. On arriving there it was discovered that Mr. and Mrs. Colchester-Wemyss had provided hospitality in the shape of a substantial tea. The refreshment having been partaken of and the hospitality acknowledged by the President, Mr. Colchester-W emyss conducted the party over the quarries in which the Limestone is worked for making cement. These were all in the Upper Series, that is to say, in the Crease and Whitehead Limestones. From the Cement Works the party proceeded to Mitcheldean Station, whence they returned by rail to the headquarters at Gloucester. t<:orr

t'l c>< Cl ~ ,--,----, o: o>-3

>-3 ~ l'l "J Old 7led,S , o ~ U2 ,.. :;; " '.{ >-3 ~A~ .' ,_ ,": ' ~, ,~ . o

'.z;udlCffY . '"t:I (%j B J~ "Yrenlock~ I/p. Ua n()oYf1I;tj -,

FIG . l.-O~OIOGICALMAP of th e FOR~STOF DSAN and part of the WYll: VUUY, includi ng the country vis ited on Monday, Augu st 6 (N.E. of the Fores t of Dean), Tuesday, Ang Dst 7 (Wostbury .on-E;cvern and ), and Wednesday, Aug ust 8 (Wye Valley). Scale, four miles to one incb.-From the Geological Survey Maps. WYE VALLEY, AND SOUTH WALES. 545

Tuesday.-A journey of eleven miles on the carried the geologists from Gloucester to Newnham. The line first crosses Olney Isle, an alluvial flat enclosed by two arms of the Severn. Telford's graceful one-arch road-bridge over the west arm attracted attention. The rail runs on the Lower Lias to Churcham, and then on the New Red Marl to Newnham. At Newnham Station they were met by Mr. Gwinnell, who acted as conductor during the day. From a neighbouring bridge he pointed out the Keuper Sandstone, which is well exposed in the midst of the red marls in the railway cutting. The old Roman road from the Forest of Dean to the Severn Ferry was crossed, a heap of pseudo-volcanic material derived from the blast furnaces and laid bere for road-metal attracting much attention on account of its structure, and especially by the presence of free sulphur, evidently due to changes subsequent to solidification of the slag. Aft.er a brief examination of a recent cuttingin tbe marls, the party proceeded along the terrace gardens, where a good view was had of the position of the great N. to S. fault and the striking contrast in the scenery on either side of it, the Old Red rising steeply beyond the line of fracture and being capped on tbe distant ridge by Carboniferous strata. Proceeding to the churchyard, situated on a vertical cliff of Red and Green Marl about 70 feet high, a splendid view was obtained of the great horse-shoe curve of the Severn, the Vale of Glo'ster, and tbe distant Cotteswolds. Here the Director described the topography and physiography, remarking especially on the erosive action of the stream and tides on the convex sides of its curve and the accumulation of alluvial deposits on the concave portions. The phenomena of the "bore," so well seen at this spot at spring tides, were also described. The base of the cliff at the ferry was next examined and seen to consist of many thin strata of various tints of red, green, and grey marls, of very unequal hardness, and consequently weathering unequally, producing a series of ledges. A walk of one mile along the river bank brought the party to Broad , where the Mountain Limestone from the Avon gorge, being landed there for road-metal, was examined. Continuing along the river bank for another mile the 546 EXCURSION TO THE FOREST OF DEAN, celebrated at Westb ur y-on-Severn was reached, just before which the Director, with the aid of a large map and vertical and horizontal sections of the cliff on a large scale, explained the general features. The state of the t ide compell ed Lower Lias.

) [onotis bed,

Es th crl a zone.

Up. Pecten bed. Low, Pect en bed . Avicula contortu find Cardium shal es. !Bono bed. ~~~~;.r'., Pullastra bed,

-_>"<...... ~.-..../I -~ ,Z::- -::.:;-. Rhretic ma rls. ~_-:::... --::-:.- -..:. -~./- --:::\- ~;;~~;;E ~~ K eu p e r marls. Fig. 2. Vertical section of t he Rheetic Series at Garden Cliff, Wes tbury. on-Severn , Glouce stershire. (Re duced fr om secti on by Mr. R. Bther idge, F.R .S., in ' PrOD. Cotteswo ld Club,' 1865.) the party to proceed along t he cliff to the far end before descending, so that t he successive strata were examined in descending order from the beds of the Planorbis zone of the Lower Lias, through the Whit e Lias Series and Bl ack Rheetic Shales to the grey Rhoo tic Marls and red Keuper Marls. The " Monotis bed" and "Bone bed" were called upon to yield considerable spoil, many good specimens of reptilian and fish bones and coprolites, mostly brilliant with golden pyrites, being carried off. The prominent cornice-like ledg es, formed by the E stheria WYE VALLEY, AND SOUTH WALES. 547

Bed, and especially by the Upper and Lower Pullastra Beds (the latter strongly ripple-marked, and though but a foot thick pro­ jecting as much as seven feet), were especially noticeable. While seated on the fallen blocks from this cornice, or perched high up on the face of the cliff, the party was photographed. The hammers of the geologists were found useful in cutting foot­ holds on the headland, whose base was under water, and which had to be rounded to avoid a long detour. After taking refresh­ ment at Westbury a two-mile walk to Grange Court Junction was made, and the train taken from thence to , crossing en route the great fault seen earlier, which here brings up the Silurian Beds against the New Red. From Longhope Station the party proceeded up Huntley Hill, an outlying part of May Hill, first passing over the Upper Ludlow sandy shales, which yielded Rome slabs very thickly crowded with molluscan shells. A small quarry in a depression showed the Lower Ludlow Beds-yielding abundant encrinital joints, and polyzoa-resting on the Wenlock Limestone with corals. A further ascent brought the party to a grand exposure of the Wenlock Limestone in a series of connected quarries along the crest of the ridge. The Limestone was very compact, and largely made np of corals, and had an irregularly undulating upper surface, on which the Ludlow Shales reposed. These latter were remarkably undulating, and the Director broached the theory that they had perhaps been deposited in this way on the irregular surface of a coral reef, for such the Wenlock Limestone here appeared to have been. After securing some good rugose and other corals the hill was descended by another route, and the five o'clock train, specially stopped for the occasion, taken for Gloucester. After dinner, and the customary thanks to the day's Director, a visit was made to the Glo'ster Museum, specially opened for the occasion, where Mr. Gwinnell drew attention to the objects of more especial interest, including the splendid series of Ammonites arranged in stratigraphical order by the late Dr. Thos. Wright and by Mr. W. C. Lucy. In the course of the evening a brief address on 'The History and Architectural Features of Gloucester Cathedral' was given by Mr. J. W. Parker, M.A., with a view of preparing the party for their visit to this edifice on the following morning. 548 EXCURSION TO THE FORES T OF DEAN .

lVednesday.-An early visit was made to the Cathedral, where the party was r eceived by the D ean, who explained the structure in detail. After leaving t he Cathedral the ge ologists, under Mr. Gwinnell's guidance, left by the for Berkeley Road Station, where the carriage reserved for the party was slipped and joined t o the local train. It proceeded via Sharpness Dock s, cross ing the To rtworth inlier of Silurian Rocks, t he buried forest at Sharpness, and t he Severn Bridge, the larg est iron bridge in Engl and. was r eached at 11.40, and the train t hen proceeded through a defile in to the Forest of Dean, which wa s crossed t hroug h its centr al part from sou th to north, man y fine expos ures of the coal-seams and thick Coal -Measure Sandstones being seen. The sylvan scenery was in m any part s extre mely beau t iful. 'I'he watershed being pierced through a short tunnel, the beautiful coombe-like valley of the was descended, the Mountain Limestone rising grandly on either side. At Lydbrook Junction, on the banks of t he 'Vye, the par ty ali ghted. The Director , wi th the aid of a larg e map , explained the geology and scenic features of the district s already passed through, and proceeded to de scribe what was ab out to be visit ed, the magnificent upper gorge of t he 'Vye, commencing just a mile beyond the .spot. A t wo-mile walk thr ough Engli sh Bi cknor and over the Coldwell R ock s, with frequent pauses to step out on the precipitous promontories of Mountain Lime­ stone and view the t owers and pinnacles of rock, their bases clothed with trees and their sides with ivy, brought the party t o Symond's Yat, and the unrivalled prosp ect from its summit, 500 feet high, of which 200 is shee r precipice . The day being all that could be desired a magn ificent view was had , and t he r esult of the combined work of running water, wind, and weather in forming the winding gorge was very apparent. 'I'he train was t ak en in the after noon for Tint ern viti. Mon­ mouth. At Tintern arrang ements for tea had been kindly made by Mrs. U pfield Gr een, and after t ea the party vi sited the ruins of the Abbey. Two hours later thc train was again taken and reached through the lower gorge of the Wye, which wa s crossed by BruneI's famous bridge. A large qu arry in the Mountain Limestone here yielded some corals, and t he Director pointed out Aust Cliff in the distan ce, celebrated for its Rhretic FIG. g.-GEOLOGICAL MAP of the Neighbourhood of OARDTFF and part of the , including the country visited on Thurs. day, August 9 IPenarth and Rumoey), Friday, August 10 (Taff Vale and Valley), and Saturday, Angust 11 (Llandafl', , &0.). Scale, fonr miles to Oneiuch.v-From the Geological Survey Maps. 550 EXCURSION TO THE FOREST OF DEAN,

Section. Cardiff was reached vid Newport about eight, the party proceeding to their quarters at the Park Hotel. Thursday.-Under the guidance of Mr. T. H. Thomas and Mr. J. Storrie the party proceeded to Rumney, where they examined the Silurian Rocks described some years ago by Professor Sollas.* By means of two anticlinals the Silurian Strata are here brought up as inliers in the midst of the Old Red Sandstone. About 950 feet of Silurians, partly Wenlock and partly Ludlow, are exposed. Ty Mawr Quarry afforded an excellent section of the "Rumney Grit," a massive iron­ stained quartzose sandstone. Casts of Otenodonta were found in the yellow sandstone known as the Discina bed, and here, too, were obtained specimens of plant-remains, including Pachytheca sphcerica. In Rumney Lane a coral bed was examined. Carriages were then taken to Roath Church, whence the party proceeded to Pen-y.lan Quarry. Here were exposed yellow and green mudstones with argillaceous sandstones weathering into spheroidal blocks. This quarry has yielded a large number of fossils, which serve to place the strata in the Wenlock Series, though the Llandovery facies of the fauna is admitted. Petraia bina and Encrinurus punctatus are abundant. In Coed-y-gores Lane a folded section of the Silurian Rocks was seen, and numerous fragments of trilobites were obtained. The section on the low bank of the Rumney River was then examined, the beds here containing Ludlow fossils and passing gradually upwards into the Old Red Sandstone. Immediately below the Old Red there occurs a brown grit containing spines of Onl'hus tenuistriatus and other fish-remains.t In the course of the morning the entire series of Rumney Silurian strata from the Wenlock to the base of the Old Red had thus been examined. The party returned in carriages to Cardiff, and after luncheon proceeded by rail to the famous cliff-section at . The state of the tide was exceptionally favourable, and on the shore at Point the beds were admirably exposed. The Lower Lias and the Rhretic Shales were well seen, and numerous organic relics obtained from the fish-bone bed.

* "On the Silurian District of Rhymneyand Pen-y-lan, Cardiff," by W. J. Sallas, M.A.. F.G.S., • Quart. Journ. Geo\. Soc.: xxxv, 1>-79, p. 475. t 'l'he fossils knuwn as Oncho» are probably fragments of Crustaceac-e­ En. WYE VALLEY, AND SOUTH WALES. 551

The walk under the cliffs from Lavernock to Penarth enabled the visitors to mark the succession of beds indicated by Mr. H. B. Woodward in the section given above at P: 530. Beneath the Rheetic Beds the New Red Marl, with its gypseous bands, was studied, and attention was specially directed to the faults which have disturbed the strata, and which in one place have caused the Rheetio Shale to be dropped down between Red nifarls. On reaching Penarth the party visited the art gallery at Turner Honse, where they were received by the proprietor, Mr. J. Pyke Thompson. In the evening the Members of the Association attended a reception at the Museum to which they had been invited by the President and Committee of the Cardiff Natural­ ists' Society. On arriving at the Museum they found that arrangements for their comfort had been made on a most liberal scale, and a large party of local naturalists had assembled to greet them. The Museum collections, both scientific and artistic, were greatly admired, and the assem­ blage of local fossils was naturally a source of much interest. Prof. R. VV. Atkinson, the Honorary Secretary of the Society, and Mr. J. Storrie, the Curator, were, with others, indefatig­ able in their attentions to the visitors. In the course of the evening congratulatory addresses were delivered by Mr. T. H. 'I'homas, the President, and by Dr. C. 'I.'. Vachell, who until recently had for many years acted as Honorary Secretary. Speeches were also made by the President of the Association and by Prof. Sollas, and at the conclusion of the meeting the general opinion was expressed that this social gathering was one of the pleasantest episodes of the Excursion. Friday.-Mr. W. Galloway, a engineer of wide experience, and formerly one of the Government inspectors, met the geologists early on Friday morning, and acted as conductor during the day. Under his guidance they proceeded by the Taff Vale Railway to Havod Station, in the Rhondda Valley, and visited Lewis's Merthyr Colliery. Much interest was taken in the surface arrangements, the hoisting gear and ventilating fan being especially noteworthy. A large number of the party, under the guidance of the Manager and several other officers, descended the pit, and were taken through the 552 EXCURSION TO THE FOREST OF DEAN, principal workings. Both steam-coal and coking-coal are raised here from separate shafts. The new method of watering the underground roads by means of a spray to lay the coal-dust was shown inaction. Mr. Galloway's long-continued researches on the influence of dust as a cause of colliery explosions are well known to all interested in the prevention of accidents. Those who remained at the surface inspected the Welsh ovens in which coking is carried on, and witnessed the opera­ tions of coal-washing. They were afterwards joined by the visitors who had come up from the colliery, and the entire party sat down to a luncheon hospitably provided by the Directors of the Company, and presided over by Mr. W. H. Williams, the Chairman of the Company. From Havod the visitors proceeded to Quakers' Yard Station, and were thence conveyed by special train to Harris's Naviga­ tion Colliery, where they were courteously received by Mr. Forster Brown, the Consulting Engineer. This colliery is the deepest in South W ales, and the machinery is of the most approved character. Much interest was taken in the surface appliances, but there was no time for a descent. After partaking of light refreshment provided in the office, the party re-entered the special train and proceeded to Llanbradaeh, where they examined the sinking now being made by Mr. Galloway. This sinking is of interest to geologists from the fact that it is situated on the south of the great anticline, where the anticline itself has almost died out in passing eastwards. The mechanical arrangements attracted much attention, and the more adventurous of the party descended in the tub and saw the rock-drills at work. The water in this pit has been tubbed back with brickwork for the first time in South Wales.* Before leaving Llanbradach the party were entertained at tea by Mr. Galloway and a staff of ladies who had volunteered assistance, and decorated the offices for the reception of the party. The special train was then taken to Pwllypant Quarry, where a deep section of the Pennant Sandstone Rocks is exposed. The train on proceeding homewards halted at the mouth of the tunnel in order that the exposure of the lowest seams in the

* "Sinkin~ Appliances at Llanbradach," by W. Galloway. "Proc. S. Wales Inst, Eng.,' xvi, 1888, p. 107. WYE VALLEY, AND SOUTH WALES. 553

South Wales Coalfield might be examined. The tunnel itself passes throngh the Carboniferous Limestone, and on the side nearer to Cardiff the Old Red Sandstone was seen. As Friday evening was the last occasion on which the party wonld meet together at the dinner table, several speeches were delivered, and the hospitality of the Cardiff geologists duly acknowledged. An interesting function was the presentation of an address, signed by a large number of the Members, to Miss Mary Forster prior to her departure for Baltimore, U.S.A. Saturday.-The programme for this day was arranged and carried out by Dr. C. T. Vachell, assisted by Mr. Storrie. , one of the residences of the Marquis of Bute, was first visited. Carriages were then taken to Llandaff, and the party was received at the Palace by the Bishop of Llandaff and Mrs. Lewis. The shaft of an ancient Celtic cross and the ruins of the old Palace were inspected. The party next pro­ ceeded to the Cathedral, and were conducted over the building by the Rev. Minor Canon Downing. The thoughts of the geologists naturally turned to Dr. Conybeare, who was at one time Dean of Llandaff, and whose monument is here. William Daniel Conybeare was born in London in 1787. He was, in 1823, appointed Vicar of Sully, near Penarth, where he resided until 1836, when he removed to a family living at Axminster, and in 1845 he became Dean of Llandaff. With Buckland, he made a detailed stndy of the and Sonth Wales Coalfields, the results of which were published in a paper of remarkable value considering the time of its publication. The two geologists also visited and described the coast of Antrim and Derry. Weare indebted to Conybeare for an excellent account of the landslip at Axmouth in 1839, and for an exhaustive report on the position of geological science at the time the British Association was established. The' Outlines of the Geology of England and Wales,' by Conybeare and W. Phillips, is well known. The versatility of Dean Conybeare's genius is also attested by his great palooontological knowledge and acute reasoning. In 1821 he established the genus Plesio­ saurus, and so profound was his acquaintance with osteology that he was regarded by Cuvier as the founder of vertebrate palooontology in this conntry. Dean Conybeare died in 1845. After visiting Conybeare's monument the party proceeded to VOL. X., No.9. 40 554 EXCURSIO N TO TH E FOREST OF DEAN, the De an ery, where theylwere r eceiv ed by the De an of Llandaff and Mrs. Vaughan. This pl easant visit ended, t hey r ejoin ed t heir carriages and were take n t o R ad yr Quarry, where they found a good exposure of the Dolomitic Conglomerate. The n ext obj ect of intere st visited was the Marquis of Bute's vineyard, wher e :Mr. P et t igrew exp laine d hi s system of grap e cult ivation." Thence they passed to Castle Coch , r ecen tly r est ored by L ord Bute; and after luncheon visited the neigh­ bour ing quarries in which the Carboniferous Limestone is extensively worked . The last feature in the programme was a visit t o the Garth Mine, near Pentyrch, under the g uida nce of Mr. Stephen V ivi an, of Llantrissant. The ore forme rly worked in this mine is a mixture of Red and Brown H ematite, which occurs in irregular pock ets in the Carboniferous Limestone. The mine h as of late years been abandoned, but in vi ew of the visit of the geologist s the deserted workings had beeu inspected by the conduct or. Furnished with li ghted cand les, the party now ente re d by a tunnel or adit-Ievel, some 660 yards in length, driven through the solid Limestone. The are had been worked below this tunnel, and was r aised by mean s of an underground eng ine. Or iginally the workings were carried down from t he cres t of the Limestone hilI, and the h uge excavations thus made in t h e r ock , whi ch needed notimber for support of the sides, illuminated by dayl ight streaming dow n from above, formed a sight which is probably unique. Good specimens of ore and crystals of calcite were secured in abunda nce at t his par t of t he mi ne. In the darker r ecesses of the workings water had accumulated in t he deep cavities whence or e h ad been removed, and the Director tested the depth by casting great blocks of stone into the pools and listening to the noi se of t he fall as it r everberated through the subterranean galleries. When Mr. Vivian illuminated these ch am ber s by means of colour ed fires, the weird spectacle left an impression on the minds of the visitors not likely to be soon obliterated.t * See" The Vineyard at Castle Coch," by A. Pettigrew. •Trans. Cardiff Nat. Soc.,' xvi, 1884, p. 6. t For description of the Garth Mine see Mr. Vivian's paper" The Hematite Deposits of the Southern Outcrop of the Carboniferous Lim estone of South Wales," in • Proe. S. Wales Jn st ., Eng.,' xiv, 1885, pp, 164·170. Also" On th e Origin of the Hematite Deposits in th e Carboniferous Limestone," by E . Wethered, 'GeoI. Mag.' (ii), ix, 1882 , p. 522. WYE VALLEY, AND SOUTH WALES. 555

On regaining the entrance to the adit, the explorers found themselves once more in the light of day. In due course the President acknowledged the assistance which had been so generously rendered by the numerous friends who had con­ tributed to the success of the day's Excursion. And thus the week's work, which from first to last had been pleasant and successful, was brought to a formal conclusion, and the Members separated on the Saturday evening with the most satisfactory recollections of the Long Excursion of 1888.

REFERENCES. Geological Survey Map, Sheets 43 S.W. and S.E. (Gloucester, May Hill, and Forest of Dean); 35 (S. part of Forest of Dean and Wye Valley); 36 (S. Wales Coalfield, Cardiff, and Penarth); 20 (Laveruock). Geological Survey Index Map, Sheet 10. (This map, on a scale of four miles to the inch, will be found very convenient, as the single sheet includes the whole area visited.) Horizontal Sections, Sheets 10, 11, 12, 13, and 15, illustrate the S. Wales Coalfield and Forest of Dean. Vertical Sections, Sheet 47, Lower Lias and Rheetio or Penarth Beds of , etc. ADAMS, W.-" On the Geological Features of the South Wales Coalfield," • JOUl'n. Iron and Steel Inst.,' Vol. i, p. 13. BROWN, T. FORSTgR.~" The South Wales Ooalfield,'" Trans. S. Wales Inst. of Engineers,' ix, 1876, p. 59, BUCKLAND and CONYBEARE,-" Observations on the South-western Coal District of England," 'Trans. Geol. Soc.,' ser. 2, Vol. i, p. 210. Coal Commission Report, Vol. i, 1871. (8, Wales by Sir H. Hussey Vivian and Geo. T. Clark; Forest of Dean by J. Dickinson.) DAVID, T. W. EDGEWORTH.-" On the evidence of Glacial Action in South Brecknockshire and East Glamorgaushiro," Quart. Journ. Geol. Soc.,' Vol. xxxix, p. 39. DE LA BECHE, SIR H. T.-" On the Formation of the Rocks of South Wales and South-western England," • Memoirs of the Geological Survey,' Vol. i,1846. ETHERIDGE, R.-" On the Rhastic Deposits of Penarth and Lavernoek," 'Rep. Cardiff Nat. Soc.,' iii, 1872. --- "On the Rhretic Beds at Garden Cliff," 'Proc. Cotteswold Nat. Field Club,' iii, 1865, p. 218. GALLOWAY, W.~" On the Mode of Occurrence of Coal," Trans. Cardiff Nat. Soe.,' xvii, 1885, p. 20. GLASS, REV. N.-" Silurian Strata near Cardiff," 'Geologist,' iv, 1861, p.169. GWINNELL, W. F.-" On the Bheetio Deposits of Britain," • Proc, Athenooum Soc.,' 1886. 556 EXCURSION TO THE FOREST OF DEAN.

HARRIS, W. H.-I< Geology of Cardiff," , Science Gossip,' 1879, p. 99. HARRISON, W. JEROME.--' Geology of the and of N. and S. Wales,' 1882. (, p. 92; , p. 178; S. Wales, p. 334.) HULL, E.-' The Coalfields of Great Britain,' 4th ed., 1881. ~S. Wales, p. 88; Forest of Dean, p. 125.) JONES, JOHN, and Lucy, W. C.-I< Section of the Transition Beds of the Old Red Sandstone and Carboniferous Limestone at Drybrook in the Forest of Dean," , Proc, Cotteswold Nat. Field Club,' iv, 1868, p. 175. MEADE, R.-' The Coal and Iron Industries of the United Kingdom, 1882.' (S. Wales, p. 188; Forest of Dean, p. 223.) MURCHISON, SIR R. 1.-' Siluria,' 4th ed., 1867. PERKINS, C. H._u The Anthracite Coal and Coalfield of S. Wales," , Report Brit. Assoc.,' 1880, p. 220. PHILLIPS, JOHN.-" The compared with the Paleeozoio Dis­ tricts of Abbei-ley,Woolhope, May Hill, etc.," , Mem. Geol. Surv.,' Vol. ii, Part 1, 1846. SMYTH, SIR W. W.-' Coal and ,' 6th ed., 1886. (Forest of Dean, p.67 ; S. Wales, p. 68.) SOLLAS, W. J.-I< On the Silurian District of Rhymney," 'Quart. Journ. Geol. Soc.,' xxxv, 1879, p. 475. SYMONDS, REV. W. S.-' Records of the Rocks,' 1872. WETBERED, E.-I< On the Lower Carboniferous Rocks of the Forest of Dean," , Quart. Journ. Geol. Soc.,' xxxix, 1883, p. 211. ---"On a Section of Strata exposed in a Railway Cutting at Morse. near Drybrook," 'Proc. Cotteswold Nat. Field Club,' viii, 1886, p, 24. WOODWARD, H. B.-' Geology of England and Wales,' 1887. (Forest of Dean, p. 191; South Wales Coalfield, p. 193; Rheetic Beds, p. 248; Drift, p. 493.)