Cornell Aniversity Library BOUGHT WITH THE INCOME FROM THE SAGE ENDOWMENT FUND THE GIFT OF ea = s-s Henry W. Sage ae 1891 . ENGINEERING LIBRARY Al Arie HIME LB... Cornell ieee Library QE 262.R47S89 1885 asts adjoining Rhyl ‘inital i engr MEMOIRS OF THE GEOLOGICAL SURVEY. ENGLAND AND WALES. THE GEOLOGY OF THE COASTS ADJOINING RHYL, ABERGELE, AND COLWYN, ‘(RISEN OF QUARTER-SHEET 79 N.W.). AUBREY STRAHAN, M.A, F.G.8, _ (Wira Notss sy R. H. TIDDEMAN, M.A, F.G.S.) PUBLISHED BY ORDER OF THE LORDS COMMISSIONERS OF HER MAJESTY'S TREASURY. LONDON: PRINTED FOR HER MAJESTY’S STATIONERY OFFICE, AXD SOLD BY Lonemuans & Co., Paternoster Row; Trtener & Co., Ludgate Hill; Lzrrts, Son, & Co., Limited, 38, King William Street; Epwarp SranforD, Junior, 55, Charing Cross; J. Wrxp, 12, Charing Cross ; oa and B. ‘Giaurnes, 15, Piccadilly ; ALSO BY . T. J, Day, 53, Market Street, Manchester ; : Mosers. W. & A. K. Jonnsron, Edinburgh ; ‘Hopexs, Fieais, & Co., 104, Grafton Street, and A. Tuom & Co., Limrrep, "Abbey Street, Dublin. _— 1885, Price’ One Shilling “and Sixpence. Missing Page MEMOIRS OF THE GEOLOGICAL SURVEY, ENGLAND AND WALES. THE GEOLOGY OF ergy THE COASTS ADJOINING bh A ’. RHYL, ABERGELE, AND COLWYN, (EXPLANATION OF QUARTER-SHEET 79 N.W.) BY ! AUBREY STRAHAN, M.A., F.G.S. (Wire Norzs sy R. H. TIDDEMAN, M.A., F.GS.) qyedebeb insult wees seeretesrvavayeraoonseeeneen LONDON: PRINTED FOR HER MAJESTY’S STATIONERY OFFICE, AND SOLD BY _ Lonemans & Co., Paternoster Row; Triznen & Co., Ludgate Hill ; Lerrs, Son, & Co,, Limrrep, 33, King William Street ; EpWarpD Sranrorp, J junior, 55, ‘Charing Cross ; J. Wrxp, 12, Charing Cross; and B. QuarrtcH, 15, Piccadilly ; ALSO BY T. J. Dax, 53, Market Street, Manchester ; Messrs. W. and A. K. Jounston, Edinburgh ; Hopces, Freats, & Co., 104, Grafton Street, and A, Taom & Co., Limrrep, _ Abbey Street, Dublin. 1885. Price One a and Sixpence. dual NOTICE. ~ THE Map, of which the present explanation furnishes a de- scription, was originally surveyed by Messrs. W. T. AVELINE, W. W. Smytu, and A. ©. Ramsay, and was published in 1850. The ground having recently been re-surveyed on the scale of six inches to a mile, the original Map is now withdrawn, and is replaced by a new issue reduced from the six-inch scale. The solid rocks which occur in the district, and are described’ in this Explanation, range from the Wenlock Shale to the New Red Sandstone. The Silurian strata, after having been cleaved,. contorted, and denuded, were covered unconformably by the ‘Carboniferous rocks, which, in turn were disturbed before the deposition of the New Red Sandstone. There are thus two marked unconformabilities separating the Carboniferous series from the rocks above and below.. An important structural feature now for the first time indicated is the great dislocation that skirts the ‘east side of the Vale of Clwyd, and the faults connected with it. The distribution “of the Superficial Deposits is shown upon a separate edition of the Map. The most important of these, the Boulder Clay, contains an intermixture of detritus that has come from the north, and from the Welsh hills lying to the south-west and south. ‘The Post-glacial deposits afford evidence of recent changes of level, like. that met.with on the coasts of Lancashire and Cheshire. Some questions of economic importance are discussed in the following chapters, particularly the workable ores (including those yielded by the celebrated Talargoch Lead Mine) and the pro-- ‘bability of Middle Coa!-Measures occurring in the Vale of Clwyd. ARcH. GEIKIE, Geological Survey Office, Director-General. ‘10th July 1885. Sd A 17240. Wt. 15801, a NOTICE. : ' TE re-survey of the area embraced in Quarter-Sheet 79 N.W. has been made—to the west of Colwyn by W. T. AVELINE; thence to the Dulas by A. Stranan; from the Dulas to the Clwyd, and about Rhuddlan, by R. H. Trppeman; the remainder to the east by A. Stranan. Mr. Ave ine, as District Sur- veyor, superintended the survey of the whole. ’ -’ Two editions of the new one-inch Map are now published, one showing the drift, the other showing the solid geology; the price of each is 1s. 6d. : MLS. coloured copies of the six-inch maps are deposited for reference in the Geological Survey Office. . ‘The Memoir has been written by Mr. StraHan, with the addition of notes by Mr. TippEMay, relating to the ground for which he is responsible. , ee ote ae Appended is a list of works on the geology, &c. of Denbighshire and Flintshire by Messrs, WHITAKER and STRAHAN. Dr. C. Le Neve Fosrer, Her Majesty’s Inspector of Mines, has read the proofs of the Memoir, and has supplied some notes about the mines, &c. of the district. H. W. Bristow, . Geological Survey Office, Senior Director. 28 Jermyn Street, S.W., 9th-July 1885, CONTENTS. , : Page. Intropvuction - - - - - 7 | V5 Lo PPS DER CHAPTER I. SOLID GEOLOGY. Uprrr SILurRiAN Rocks :— ’ Wenlock Shale - S : . ta ar) CanrsonireRous Rocks :— Basement Beds - - ~ = Carbonifer ous Limestone :— ‘(1.) East of the Clwyd ° - 2 a ae (2.) West of the Clwyd - - - - 4 (3.) Lhe Blaich Limestone -. - we - 3W Millstone Grit :— The Chert Beds... =... 2 ~ ! Lower Coal Measures :— (1.) East Side. -The Holywell Sans one Geis Sandstone - 20 (2.) Vale of Cloyd - - - - - 20 Trias on New Rep Sanpsrone (Bunter) = - - - 25 shegy, “SE % CHAPTER II. SUPERFICIAL DEPOSITS. GuactaL Beps anp PHysicaL GEOGRAPHY - - - 28 GLACIAL STRLE - - - - - - 88 Post-GiaciaL Bups :—Calcareous Tufa - - - 40 Peat and Alluvium - - - 40 _ Blown Sand. = go - 44 CHAPTER III. -ECONGMIC GEOLOGY. Minine :— LraDsND Zinc ORES - - - 3 - 45 Talargoch Lead Mine - - = - 46 Talacre Mine - - - - 4g Other Mines - - 3 oo oR wl Minine—cont. HamMatTIte - - - - 5 witH NIcKEL AND CoBALT - - - 54 WITH COPPER - - - - Prrovusire (BLack OxIDE or MANGANESE) -— - 7 ON THE PROBABLE OCCURRENCE OF COAL UNDER THE BuntTER SANDSTONE - - - = A Quarries, Brick-pits, &e. - = - : = APPENDIX I. Observations on UNDERGROUND TEMPERATURE in the Talargoch Lead Mine -- - - a 2 . < APPENDIX II. ‘List of Works .on the Geology of Flintshire and Denbighshire - ~PLatE.—Map and Sections of the Talargoch Mine and Neigh- bourliood. ; w Inpex. Page. 52 54 55 56 56 57 58 59 THE GEOLOGY OF THE COASTS ADJOINING RHYL, ABERGELE, AND COLWYN. INTRODUCTION. THE Map now to be described includes a portion of the coast of North Wales, about 14 miles in length, extending from near the Point of Ayr to Llandrillo-yn-Rhos, near the Little Orme’s Head. For the greater part of this distance the shore is formed by glacial deposits, or by the later spreads of Alluvium and Blown Sand which overlie them. In one spot only the solid rock (Carboniferous Limestone) runs out into the sea, forming the bold cliff of Craig or Penmaen on the east side of Colwyn Bay. Inland, the eastern side of the Map is occupied by a portion of the escarpment of Millstone Grit and Carboniferous Limestone which runs southwards through Flintshire, and by the northern termination of the-range of Silurian rocks which enclose the Vale of Clwyd on the east. The centre of the Map includes the wide alluvial flats and gentle boulder-clay slopes which overspread the New Red Sandstone of the Vale of Clwyd ; while westwards the Limestone range of the west side of the Vale of Clwyd is shown skirting the coast from Abergele to Craig near Colwyn, where it strikes out to sea, to reappear in a distance of about three miles in the bold hills of Bryn Eurian and the Great and Little Orme’s Heads. The following table includes all those formations which are distinguished by colour on the two editions of the Map :— Blown Sand. Recent and Post-Glacial - Bee Calcareous Tufa. Boulder Clay Glacial* - - - -{ Sand and Gravel (in, under, or over Boulder Clay). Trias - - Bunter - - Mottled Sandstone. ( Lower Coal Sandstone. Measures. Shale. Shales and Sandstone fadinntren 4 Millstone.Grit = - (West side). Carboniferous Chert Beds (Kast side). Carboniferous Black Limestone. Limestone. Limestone. | Basement Beds Red Conglomerate. C 2 ( + 5 Z " . Upper Silurian - Wenlock Shale | ee a ae d oe * Coloured only on the edition of the map for Superficial Geology. 2 UPPER SILURIAN ROOKS. CHAPTER I. SOLID GEOLOGY. | A detailed description of the physical geography of the district falls conveniently into the section of this Memoir which is devoted to an account of the Superficial Deposits. . The description ‘of the various subdivisions of the solid rocks will therefore be now proceeded with, the oldest being taken first. Upper Siturian Rocks. Wenlock Shale. The Wenlock Shale consists of a great thickness of pale:gray ‘sandy shales or mudstones, with beds of ‘fine-grained’ hard ‘sand- stone intercalated at various horizons. The whole series (except- ing the sandstones) is cleaved, in some cases the structure being sufficiently well developed to have led to trials for slates having been made. The slates, however, are of extremely-bad: quality, and the quarries are all abandoned. ‘The direction of the eléavage on the east side of the Vale of Clwyd is fairly constant ‘at E. 10° 8., while on the west side it varies from E. 45° S. to E. 5° S., showing, nevertheless,;a prevalence in a direction of about E. 10° §. It is interesting to note that the very numerous synclinal and anticlinal folds into which these beds have been bent have their axes arranged parallel to the direction of the cleavage. An instance may be seen in Cwm Mountain, where the axis of an anticlinal fold is clearly shown by the form of the outcrop of a bed of sandstone. It may be inferred that the cleavage and folding — were produced by the same cause, namely, pressure in the direction N. 10° E. Subsequently it will be shown that. the cleavage and partial metamorphism which accompanied it were accomplished before the commencement of the Carboniferous Period. As shown on the.map the general dip of the Silurian strata on the west side of the Clwyd is towards the north-east: An observer, therefore, travelling in a south-westerly direction, while crossing many undulations, passes generally from higher to lower beds. The lower part of the Wenlock series, known as the Denbigh Grits, is finally reached in the valley of the Conway, near - which it is succeeded by the Tarannon Shales and finally by the Bala Beds (Lower Silurian). The area occupied by these rocks has been described as a whole by Srr ANDREW Ramsay.* * Geology of North Wales. Memoirs of the Geological Survey, yok, iiil., second edition, 1881. 5 CARBONIFEROUS ROCKS. —BASEMENT BEDS. 3 CaRBONIFEROUS Rocks. Basement Beds. . One of the greatest unconformities to be met with in the British Isles exists between the Wenlock Shale last described and the Basement Beds of the Carboniferous Series. These latter may be seen in more than one section to rest in the form of coarse conglo- merates on the edges of the upturned Silurian strata, showing a discordance apparently as great as that which exists between the pebbly beach of a modern sea-shore and the rocks of the cliff against which it is banked. Even without such visible signs the uncon- formity would be inferred from the fact that a short distance west of the margin of this: map the Carboniferous rocks pass suddenly on to the Lower Silurian strata, and also in Anglesea on to rocks of very early date, thus clearly indicating a great upheaval and denudation of the Silurian system in pre-Carboniferous times. In addition to this, the Carboniferous Conglomerates and Limestone, resting generally at a gentle angle on the upturned Wenlock Shale, show none of the cleavage. or folding so noticeable in the older rock ; while, on the other hand, the fragments of Wenlock Shale occasionally found embedded in the base of the newer series arc as much metamorphosed as the parent rock itself. It is known, however, that the phenomena of cleavage and meta- morphism as displayed in the Wenlock Shale can only have beeu produced under certain conditions, namely, that the strata should not only have been subjected to compression in the direction N. 10° E. as before mentioned, but that they should at the time have been deep-seated; the weight and non-conducting properties of a great mass of overlying strata being essential to the produc- tion of the observed effects. This “cover” appears to have - been, provided in the mass of the Upper Ludlow Beds and the Tilestones, which attain a great thickness in Central Wales, and, as there is reason to believe, formerly overspread the Wenlock Shale of North Wales. For, though not found in! situ in any part of North’ Wales, their débris furnished the larger part of the materials of which the Carboniferous Basement Beds are composed, as will now be shown. we _ The Basement Beds are extremely variable in thickness and character. On the east of the Vale of Clwyd-they appear in the form of a red conglomerate with small pebbles (about half an inch long) in the lower part, and of flaggy red sandstone and red shales in the upper part. The conglomerate is seen in a lane near Pentre-cwm,.and near the Cwm Iron-mine. A field above ‘Pentre-cwm is strewn with fragments of red flags, while some old shafts in the slope above have disclosed bright red and green laminated shales. The last indication of the presence of these beds occurs at the Cwm mine, where a little laminated red: shale is visible. At this point the beds are lost under the drift, but there is little doubt that the Basement Beds here thin out, leaving the limestone in contact with the Wenlock Shale, as is the case throughout Flintshire. This thickness of this subdivision between 4 . CARBONIFEROUS ROCKS. Pentre-bach and Pentre-cwm, is about 95 feet, west of Marian- bach not more than 50 feet, while at Marian it has thinned out, the rate of attenuation being about 1 in 55. On the west side of the Vale of Clwyd the Basement Beds attain agreater development. Their occurrence near Abergele was first noticed by Mr. J. Price, by whom they were pointed out to Mr. Bowman. They were described by Mz. Bowman in 1841,* and in greater detail by Mussrs, SrraHAN and WALKER in 1879.t The beds have been repeatedly proved in the shafts sunk in search of iron-ore along the foot of the limestone escarpment, but the best exposure occurs in Ffernant Dingle,—a deep:ravine about one mile south of Liysfaen, where an uninterrupted view of the lower part of the series is afforded. The upper part and junction with the limestone is seen in a farm-yard at Bryniau Cochion, where red-stained impure limestone rests conformably on green and purple shales, with rather a sharp line of demarcation.{ The ~ slopes below are formed of a conglomerate of green and yellow sandstone pebbles in a red and green matrix, associated with mottled red and green shales. These are succeeded southwards by a deep-red conglomerate, which runs up the dip-slope by Pen- y-dared and Tyn-y-pwll to the top of the Ffernant Dingle, where the section is continued as follows, still in descending order :— Section in Ffernant Dingle. : Feet. (Red conglomerate - - - Soft bright-red sandstone. - - Coarse conglomerate - | - - Deep-red marl weathering into cubes - Soft red sandstone with green blotches Deep-red clay crammed with pebbles - Soft red micaceous sandstone with pebbles Impure limestone (cornstone) .- ” Carboniferous g Hard red sandstone crammed with red an Basement Beds. } green pebbles - - : : Impure limestone (cornstone) Red shale oo - Fine gravelly conglomerate Impure limestone (cornstone) - Conglomerate of red and green pebbles in mottled red and green sandy matrix. — Impure limestone containing two beds of green s L sandstone pebbles in a sandy matrix - - 10 10. WHO HMAdwwa $901 colt eal 1M ree 8 a Boa gp ew ee 12 Wenlock Shale i gs - - : 80 * Trans. Geol. Soc., ser. 2, vol. vi. p. 195. “t Quart. Journ. Geol. Soc., vol. xxxv. p. 268. { Near this farm there are hollows in the limestone filled with a gravel composed entirely of pebbles derived from the Basement Beds. They are at a higher level than is now attained by the conglomerate in the’ neighbourhood, and were probably filled at an early date, before the outcrop assumed its present form. Near Tan-yr-ogof, on the east side of Liandulas, there are four caves or old water-channels in the limestone. two of which are filled with a similar gravel, now hardened into a rock, and over- laid by stalagmite and laminated cave-earth. The streams which brought the pebbles so far from their original position in the conglomerates must have had considerable volume and power, and probably flowed at'a period when the drainage of the country was different. The occurrence of the pebbles here was first noticed by Mr. Trimmer. BASEMENT BEDS. 5 The pebbles in these conglomerates are, as stated, red, green, or mottled, the green colour predominating towards the upper part of the subdivision. In other respects they present a remarkable uniformity. They are composed of a soft micaceous sandstone, liver-coloured’ when fine-grained, or purple when of a coarser texture. They split easily, and from their oval flattish shape have evidently been derived from a well-bedded flaggy sandstone. In colour and texture they resemble the Tilestones or newest Ludlow rocks as developed in Central Wales, and on the southern flanks of the Lake District mountains, The presumption that they have been derived from one of these formations is confirmed by the fact that they contain fo:sils of undoubtedly Upper Silurian age, and 90 per cent. of which occur in the Ludlow rocks. ‘The following were identified by Mr. Erneripes.* .Orthis filosa, Sow. » lunata, Sow. » elegantula, Dalm. gy -ertispa, M‘Coy. Chonetes striatella, = lata, Dalm. (abundant). Spirifer crispus, His, (abundant). » elevatus, Dalm. Rhynchonella Stricklandii, Sow.? or borealis, Schl. Pterinea retroflexa, Wahl,, or lineata, Goldf. (abundant). Orthonotus. , Arca (or Pterinea ?) ° Theca (?) Tentaculites ornatus, Sow. Holopella. These fossils are found only in the pebbles. No organic remains contemporaneous with the deposit have yet been dis- covered. : It is noticeable that the Wenlock Shale on which the Basement Beds rest in all this neighbourhood, is conspicuous by its absence in the materials of the conglomerate, except only for a few angular fragments at the base, which have obviously been detached from the immediately underlying beds. Taking into consideration the distance to the nearest locality where Upper Ludlow rocks and Tilestones occur én situ in Central Wales, and the fact that over a large part of this space the Car- boniferous strata were laid down ona deeply denuded surface of Wenlock Shale or older rocks, it would seem as though the conglomerates, if derived from this direction, should have con- tained at least as great a proportion of Wenlock as of Ludlow débris. For the same reason it is not probable that the transpor- * Quart. Journ. Geol. Soc., vol. xxxv. p. 272. The specimens are in the Museum of the Geological Society of London. 6 CARBONIFEROUS ROCKS. tation was from the west or south-east or east. Towards the north and north-east, however, it is not improbable that thesé newest Silurian strata may exist at no great distance. The general dip of the Wenlock: Shale is towards the north-east,—a dip which, as before mentioned, leads to the overlap of the Silurian by the Carboniferous system towards the west. If these relations are preserved. beneath the Carboniferous rocks still further towards the north-east, where they are overflowed by the Irish Sea, the Ludlow rocks will naturally succeed the Wenlock Shale at no very great distance, and may have formed the source of this great! mass of purple pebbles, on the supposition of the transportation having been: from the north or north-east. The base of the conglomerates may be readily traced from Ffernant Dingle westwards through a small pit at about 150 yards distance, where the junction with the underlying Silurian rocks is again exposed, to T'wynan-uchaf, near which the conglomeratic red and green cornstone is seen dipping towards the north-north- east at 25°; and 400 yards north-west of this farm the same bed was met with in a trial for hematite. At this point the boun- dary is lost sight of beneath the Drift, but is presumed to trend northwards, entering the present Quarter-sheet near Pen-y-dared, and running thence to the east and west fault, near which the base of brecciated cornstone is once more exposed to view, The slope below the limestone of 'Ty-mawr' is formed of green and red conglomerates, us may be seen in numerous small sections, one of the hest being in the side of the lane leading up the hill from Pen- lwys (Pile house). . Near this house the position of the base is accurately fixed by the occurrence of a trial for hematite and a quarry in the Wenlock Shale close together. The former shows red shale and friable sandstone, or weathered cornstone, dipping northwards at 11°; the latter Wenlock Shale of the usual character dipping east-north-east at 12°. North of this point the base is. concealed by Drift, but the junction of the subdivision with the limestone may'be easily traced at the foot of the steep limestone cliff of Penmaeu-rhos. On the west side of Colwyn Bay the Basement Beds are altogether absent. Eastwards and southwards the Basement Beds may be followed as far as the south end of the Vale of Clwyd, forming everywhere (except where cut out by faults) a narrow belt separating the limestone from the Wenlock Shale. Their description is continued below by Mr. TrppEmaN, by whom they were surveyed. It will be noticed that the conglomeratic character. is lost towards the south, where the beds consist of flaggy and ripple-marked red and green sand stones and shales :— The- Carboniferous Basement Beds east of the Dulas Valley run along the junction of 79 N.W. and S.W., and are thrown backwards and forwards by several faults; so, necessarily some ef the places mentioned occur.in the Quarter-Sheet south of that now described. CARBONIFEROUS LIMESTONE. 7 ‘East of the bold limestone hill of Pen-y-corddyn-mawr a fault running nearly along the road which goes by Garth-goyof brings up the Basement Beds. Several shafts or trials for iron have been made here; one about 300 yards fron the house exposed purple sandstone. This must be near the base, judging by the exposure of Wenlock Shale in the valley adjoining. In the recess of the limestone hills E.N.E. of Garth-gogof, these roeks, where weathered, show a soil of white clay with quartz pebbles, yellow sand, grey clay, &c., but no actual sections are visible. Beyond the next fault at the corner below the limestone, red marls were visible; and one-third of a mile west of Nant-ganol at the bottom of this series red and green sandstones and marls were seen resting on the Silurian Shales. At a’shaft hard by were sandstones, iron- stones, bad: limestones (or cornstones), and a conglomerate made up of shale fragments. These beds are dipping apparently at an angle of 30° from N. 30° E. to N..30° W. At the base of these beds again, west of the fault which runs to the S.S.E. from near Tyddyn-uchaf, the dip appears to be at 35° to the N.N.W., but in some shafts still further to the dip the Silurian rocks again seem to be touched without going through any great thickness of Basement Beds. : [wo small faults north of Ty’n-y-coed let down a tongue of limestone from the escarpment, and here also the Basement Beds consist of red and yellow shales and sandstones. Another large ~* drift” has been made near the base, in these beds, on the left bank of -the Gele. The beds are not well seen, but most of the stuff brought out consisted of a grit impregnated with hematite. ‘The Basement Beds beyond this point are well in the map to the south. Along the line of fault mentioned at Garth-gogof, about a mile from that house is seea an outlier of the Basement Beds faulted: against the Wenlock Shale, and a large quantity of ‘hematite was obtained from the fault. This is west of Ty’n-y- caeau.* There can be little doubt that the fault is the a a CanBONIFEROUS LIMESTONE, (1.) East of the Choyd. 'This formation is casily separable in this areainto an upper sub- division of thin-bedded black limestones, and a lower subdivision in which is included the great mass of nearly homogencous grey and white beds, with the lower impure, and the upper, cherty limestones. ay A more detailed subdivision of the series has been.made hy Mr. G. H. Morton in the valuable papers in which he records the results of his examination of the Carboniferous Limestone and Cefn-y-fedw Sandstone [Millstone Grit] of Flintshire and * Called Pon-y-coed on the One-inch Map. _ 8 CARBONIFEROUS ROOKS. Denbighshire. The classification of the limestone of this neigh- bourhood adopted by Mr. Morton is as. follows* :— Upper Black Limestone. Upper Grey Limestone. Carboniferous inane] Middle White Visaasiona Lower Brown Limestone. But though each of these subdivisions (excepting the Upper Black Limestone, which changes its character southwards) has been recognised by Mr. Morrow through a large part of the Carboniferous outcrop in North Wales, yet the three lower present such slight lithological differences, or shade so gradually one into the other, as to be scarcely capable of being distinguished by colour on the Map. In the following description, however, the position of the beds in Mr. Morron’s classification has been noted in each case. Rising abruptly from the drift-covered plain near Prestatyn and Meliden, the grey and white limestones form a conspicuous escarpment running southwards through the whole length of Flintshire, and attaining heights of 800 to 1,000 feet above the sea. Dyserth Castle, Graig-fawr (500 feet), Moel Hiraddug (866 feet), and the Gop Hill (819 feet) are some of the most conspicuous points in the part of the county included in this Quarter-Sheet. The abrupt termination of the limestone, and of the line of hills which mark its outcrop at the borders of the maritime plain of Rhyl] and Prestatyn, is the result of a number of faults of great size, throwing the limestone far below the level of the sea, and introducing beds of later Carboniferous age. The faults resolve themselves into two principal lines of fracture ;—the one, which may be called the Prestatyn fault, passes from Prestatyn in a south-westerly direction along the foot of Carreg-y-fran, and shifts the outcrop of the Black Limestone from near Prestatyn to beyond Meliden; the other, which may be called the Vale of Clwyd fault, runs at the foot of Graig-fawr, by Dyserth Water- fall, below Moel Hiraddug and Cwm Mountain, and thence up the whole length of the east side of the Vale of Clwyd. Along the whole of its course this fault throws down on the west side the limestone and later Carboniferous Beds which underlie the New Red Sandstone of the Vale of Clwyd, and may be considered one of the principal agents in the production of this remarkable Triassic outlier. From its size and important effect on the physical geography of the region it may take rank as one of the great faults of the British Isles. In the neighbourhood of this fault the limestone is smashed up and much altered, but, at a short distance from it, assumes its ordinary character, and prevalent south-easterly strike. Follow- ing the base from near Dyserth, we find the limestone resting conformably on red conglomerates, and tending to pass down into them by an intermediate stage of impure but fossiliferous lime- * Proc. Liverpool Geol. Soc., vol. iv. p. 390.- CARBONIFEROUS LIMESTONE, stones, shales, and sandstones of variable tints. These beds are exposed in an old quarry between Pentre-bach avd Pentre-Cwm, where the following descending section was observed :— : Ft. Ins. Grey crystalline limestone - - - - - hale = - - - - eee 01 Earthy limestone weathering into a yellow friable rock, with plant remains = - er rs - 10 Blue argillaceous limestone, weathering into spheroids 07 Earthy crystalline limestone, with bands of fine-grained limestone, containing Athyris Royssti - - 1 6 Black shale and nodular argillaceous limestone - 0 6 Massive grey limestone - - - - - 5 0 Bituminous limestone with plant remains - - 2 6 White sandy bed and shale - - - 10 Bituminous limestone, full of plant remains and threads of coal at the bottom, and containing Lithostrotion irregulare and Huomphalus - - 30 Blue argillaceous limestone, weathering into spheroids 0 5 Green shale - - - - - - 0383 Hard white sandy bed (calcareous) - - : 0 8 White shaly nodular bed (a weathered argillaceous limestone) - - - - . - 0 10 Very hard bluish crystalline limestone - - 60 Flaggy impure limestone - - - : 0 10 Argillaceous limestone - - - “- 0 5 * Yellow and green shale - - - - - 0 3 Hard bluish limestone . - - - - 6 6 Beds not seen - ode gee es, ee ee CBO Sandy and calcareous shale, with Athyris Royssii, and plant remains; passing up into bituminous lime- stone - - - - - - 5 6 Hard grey limestone, with Athyris Royssit - 5 6 Yellow calcareous shale - - & : 1 0+ Beds not seen (about) - - - - - 6 0 Basement Beds: red shales, flags and conglomerates. — 55 4 The same beds are exposed in several old mining hillocks and small quarries about the south side of Mvel Hiraddug, and near Mariav. They are everywhere characterised by the impurity of the limestone, and its interstratification with shales and calcareous sandstones ; and are always associated with a ‘very fine-grained variety of limestone of a pale blue colour, a porcellanous texture, and leaving a soft yellow argillaceous residue on weathering. The most abundant fossils are the Athyris Royssti and the plant- remains, which appear to belong to the genus Sphenopteris, bat are generally too obscure for recognition.* Spirifera lineata, Mart., Syringopora sp.? and Zaphrentis sp.? have also been observed by Mr. Morron. The occurrence of threads of coal, plant-remains, and a coral, in the same bed, is noticeable as indi- cating the approaching invasion of a littoral zone by oceanic conditions. * These were first noticed by Mr. H. G. Morton, British Association Report for 1870, Trans. of Sections, p, 82. 10 CARBONIFEROUS ROCKS. These beds, and the red conglomerates beneath them; present a very striking similarity to the subdivisions of Lower Limestone Shales and Basement Beds that have been traced at the base of the Carboniferous rocks in the North-west of England. In the present district, partly from the fact that they pass up into the overlying mass of limestone, and partly because they are concealed by Drift for a great portion of their outcrop, it has not been thought advisable to separate them by colour. On the west of the Clwyd, it would be still more difficult to make any sub- division, in spite of the comparative absence of Drift. The great mass of grey and white crystalline limestones succeed these passage beds (or Lower Limestone Shales). They are distinguished in a general. way by their more massive bedding, erystalline texture, and the absence of shale or sandstone. ‘They are exposed for a great thickness in the sides of Moel- Hiraddug,* and are largely worked in quarries at the north end of the hill for building and agricultural purposes, and for mixing with other ingredients for the manufacture of hydraulic cement. The stone contains more than 98 per cent. of carbonate of lime, as shown by the fellowing analysis} :— : Lime - : - . - 54° 664 ° Magnesia - - - - 0°201 Silica - - - - . 0°905 Alumina - - - - 0°010 Potash - - - . 07040 Tron oxide. - - . - 0°029 Manganese oxide - ~ - 0°018 Humus - - - « - 07268 Carbonic acid and water - - 43°865 100-000 A very pure limestone was formerly worked at Bryniau near Meliden for use in the Alkali Works at Prestatyn, now inactive. The hill-on which the ruins of Dyserth Castle stand is composed . of limestone belonging to this part of the series} A short distance to the east the same beds are intersected by a deep and picturesque ravine enclosed by vertical cliffs. The form of the ravine is determined by the intersection of a fault or strong joint, running E. 15° §. and said to contain copper, with a number of smaller joints running N. 18° W., partly open and partly filled with cale-spar, The ravine at present is nearly dry, but trom its size and depth may not improbably have once formed the site of onc of those great springs common in the limestone. A very powerful issue, known as the Ffynnon Asaph, and second only (in this county) to the famous St. Winifred’s Well at Holywell, takes place at Marian Mill at about two-thirds of a mile distance. ' * The whole of the limestone of this hill, with the doubtful exception of some of the top, is referred by Mr. Morron, as he informs me, to his ‘ Lower Brown” division. gz + By Mr. M. A. Gaas, of Rhuddlan. t Referred by Mr. Morton to his “Middle White” subdivision. CARBONIFEROUS LIMESTONE. II Fossils are fairly abundant, but from the nature of the beds very difficult to extract. The following were noticed in a quarry at Plas-on-bach, near Marian, in beds about 500 feet above the ‘base of ‘the limestone :—Reef-corals (principally Lithostrotion irregulare\, Euomphalus, sp.? and Athyris ambigua, Sow. Spi- rifera lineata, Phil. is noted by Mr. Morton as being usually one of the earliest fossils in the Carboniferous Limestone ot North Wales, but in this neighbourhood Athyris Royssii is remark- ably abundant in the lowest beds, as noted above. The plant-- remains are confined to the lower impure beds of the limestone, and, as will be subsequently shown, to the highest argillaceous- limestones which form a passage up into the Millstone Grit. The upper part of the limestone is distinguished by.being more cherty and less homegeneous than these massive beds,—a character that becomes still more marked in South Flintshire; it is also more fossiliferous.*. The beds are exposed in numerous quatries. and natural sections in the hill-side between Meliden and’ Prestatyn, and, though traversed by many small faults and undulations, preserve 2 general dip towards the east-north-east so as to present a fairly continuous ascending sequence. The massive white and grey limestones of Bryniau (before alluded toy and of Nant-yr-Ogof are succeeded west of Gwaenysgor by a light brown limestone with nodules of chert. This again is over- jain further north by a more thinly-bedded darker stone with more- abundant chert. A large quarry in this part of: the series shows. in the lower part dark-brown and black limestone with thin shales, and chert in bands and nodules; the shales containing the- remains of Polyzoa, and the limestones possessing the property of forming an inferior hydraulic cement. The upper part of the quarry exposes lighter coloured yellowish thin-bedded limestone with shale partings. Finally, in the hill-side above Tyn-yr-allt,+ near Prestatyn, there are seen thin-bedded grey and brown limestones with thin shales, and chert-nodules and bands, some of the latter containing numerous casts vf Encrinite stems and Foraminifera. ‘These are succeeded by the Black Limestone sub- - division. Beds of the same age crop out in the Gop Hill near New-- market, and, in consequence of the alternations of hard and flagoy- limestones, give rise to regular terraces in the hill-side. Near the base of the hill on the west side there runs a black bituminous limestone, smelling strongly when struck; while to the north- west of Marian there is a hard white limestone with a saccharoid texture. A shaft on the north of Gop Hill has traversed a little thin-bedded sandstone with impressions of Productus scabriculus and Streptorhynchus crenistria,—possibly an attenuated representative. of the thick sandstones that are interstratified with the limestone in South Flintshire. The above instances will serve to show that. this part of the Carboniferous Limestone is very variable. * This is the “ Upper Grey” subdivision of Mr. Morton. } Spelt Tan-yr-allt on the one-inch Map. A 17240. B 12 , CARBONIFERQUS ROCKS: The chert which is so abundant in these beds occurs either as nodules or in bands of four to six inches in thickness. The bands. are frequently made up of the remains of Encrinites and Foraminifera, and thus differ from the overlying Chert Beds of Millstone Grit age, the mass of which is devoid of organic remains, The larger fossils also in these limestones are silicified; the, carbonate of lime of the test, especially, of the Producti, having been replaced by a form of. chalcedony known as Beekite.* The great abundance of chert in the limestones of North Flintshire appears to compensate to some extent for the absence of the sandstones before alluded to as being intercalated in South Flintshire. , . The absence of well-marked horizons in the limestone series makes it difficult to detect faults, though doubtless they are numerous, and consequently impossible to measure accurately the thickness of the subdivision. It may be roughly estimated that between the top of the Basement Beds and the base of the Black Limestone there are from J,000 to 1,200 feet of strata.t The following fossils have been observed in the upper part of this subdivision of the limestone at Tan-yr-allt, near Meliden, and at Tyn-yr-allt,t near Prestatyn :— , Spirifera glabra, Mart. » pinguis, Sow. Terebratula sacculus, Mart. Productus aculeatus, Mart. Or this resupinata, Mart. And in the most’southern of the quarries in the Coed-yr-Esgob, near Prestatyn, Mr. Morrow has found:—. ~ ... : Cladodus mirabilis, Ag, (teeth of). *Goniatites sphericus, Mart. (or ?crenistria, Phil.) Orthis -resupinata, Mart. ; Productus semireticulatus, Mart. . Spirifera trigonalis, Mart., (var. bisulcata, Sow.) =; cuspidata, Mart. ai glabra, Mart, At the Gop, near Newmarket, the following were collected by Mr. Morton :— = Evuomphalus Dionysii, Goldf. Athyris Royssii, L’Eveillé. Chonetes papillionacea, Phil. Productus aculeatus, Mart. tae cora, D’Orb. ° - giganteus, Mart. : semireticulatus, Mart. Spirifera trigonalis, Mart., (var. bisulcata, Sow.) Lithostrotion Martini, Edw. & Haime. 7 * Geol. Mag., dec. 2, vol, vi. p. 334, 1879. + The thickness assigned by Mr. Morron is 950 feet, Proc, Liverpool Geol. Soc., vol. iv., p. 393. t Spelt Tan-yr-allt on the one-inch map. ‘ CARBONIFEROUS LIMESTONE. 13 In a quarry at Axton,.in the top of the subdivision, and immediately underneath the Black Limestone, Mz. Morron obtained the following species :— * Nautilus planotergatus, M‘Coy (=Discites Lavel- anus, Koninck). *,Orthoceras, new sp. Bellerophon, sp. Euomphalus Dionysii, Goldf. fe pentangulatus, Sow. * Macrocheilus imbricatus, Sow. Straparollus costellatus, M‘Coy. Natica ampliata, Phil. » Grata, Phil. (=Narica lirata). *Littorina? new sp. Loxonema sp. * Porcellia. Puzo, | Koninck, * Ambonychia vetusta, Sow. Aviculopecten circularis, Koninck, Jimbriatus, Sow. Edmondia unioniformis, Phil. Sanguinolaria sp. Athyris Royssii, L’Eveillé. » ‘planosulcata, Phil. » SP. *Discina nitida; Phil. * Orthis Keyserlingiana, Koninck. » ° resupinata, Mart. af roductus cora, D’Orb. ’ i aculeatus, Mart, » | fimbriatus, Sow. “5 giganteus, Mart, * 3% latissimus, Sow. » | longispinus, Sow. * 5 plicatilis, Sow. 7 punctatus, Mart. ~ % pustulosus, Phil. is semireticulatus, Mart. * striatus, Fischer, Rhynchonella acuminata, Mart. <4 pleurodon, Phil. * ” pugnus, Mart. _Spirifera trigonalis, Mar., (var. bisulcata, Sow.) duplicicosta, Phil, . glabra, Mart. > = grandicostata, M‘Coy. ey integricosta, Phil. 2 pinguis, Sow. lineata, Mart. % ovalis, Phil. striata, Mart, Streptorhynchus crenistria, Phil. B2 14 .CARBONIFEROUS ROCKS. Terebratula hastata, Sow. Fenestella plebeia, M‘Coy. Griffithides seminifera, Phil. * Amplexus coralloides, Sow.’ Syringspora geniculata, Phil. Zaphrentis Griffithi, Edw. and Haime. The species marked thus * have not been noticed elsewhere by Mr. Morton in North Wales. He states that the beds in which they occur are the “Upper Grey Limestone” of his papers. The specimens are for the most part remarkably perfect. « Near Golden Grove, at a short distance below the base of the Black Limestone, the following species were obtained :— Aviculopecten papyraceus, Goldf. Productus scabriculus, Mart. ; Rhynchonella pleurodon, Phil. (2.) West of the Clwyd. The Carboniferous rocks, as previously stated, are thrown down to the west by the Vale of Clwyd fault. On the east side of the Vale, the beds plunge at a high angle of dip beneath the New Red Sandstone, but on the west emerge at a gentler inclination, ‘ forming an escarpment, which, much broken by faults, extends from Pathin to Colwyn Bay. The portion of the escarpment which comes within this Quarter-Sheet includes the heights of Castell Cawr; Gorddyn mawr,’ Cefn-yr-ogof, and the Llysfaen hills. The range is coutinued, after a short interruption, in Bryn Eurian and the Little Orme’s Head The passage beds into the Conglomerate (or Lower Limestone Shales) are not clearly recognized in this part of the district. In the Valley of the Dulas, a very massive limestone appears to almost immediately overlie the Basement Beds, and forms an ex- tremely bold mural escarpment. At Bryniau Cochion again, and in the lane above Penlwys (before alluded to, p. 6), limestone slightly impure, but not comparable to the passage beds of Moel Hiraddug, is seen to rest upon the Basement Beds. The hills named above are composed of the same beds that form the corre- sponding features in Flintshire, namely, the lower and middle parts of the grey and white limestone subdivision. Towards the north, where the upper cherty beds (Upper Grey Limestone of Mr. Morton) would be expected to succeed, the series is terminated by modern sea-cliffs, or by inland clitfs, perhaps in part of the same origin, against which Glacial Drift is banked up. The natural junction between the Limestone and the Millstone Grit indicated at Abergele is purely hypothetical, as will be shown subsequently. A very pure white limestone has been quarried near Tan-y-gopa, and to the west of Siambr-Wen. The white limestone used for Bodelwyddan Church was obtained from these beds. CARBONIFEROUS LIMESTONE. 15 This neighbourhood was mapped by Mr. Trppeman, by whom ‘the following notes have been made :— ; _ The Carboniferous Limestone, from near Abergele to the Dulas, forms an irregular belt of hills, about a mile, sometimes more sometines less, in width. At Siambr-Wen, south of Abergele, they are about a mile and a half from the. coast, which they gradually approach in a sinuous curve until near Llandulas they are within 300 yards of it. The northern side is adorned by many fine rocky bluffs and mural scarps, some of them over- looking in dangerous proximity the picturesque modern castle of Gwrych. The limestone is of the ordinary grey and white type, but sometimes darker towards the base, as at the southern scarp of Pen-y-corddyn-bach. At Tyddyn-Uchaf, south of Gwrych, the lower beds consist of grey limestones with earthy bands inter- bedded. ; As a rule, over this area the dip is wonderfully constant in direction, chiefly to the N.N.W., but sometimes due north. The angle of dip is on the whole a little higher towards the base, where it averages 20°, whereas towards the northern side of the area it ranges from 10° to 15°. Besides the faults already mentioned (p. 7) as shifting its base, we have the following :— 3 , Siambr-Wen Fault——There can be very little doubt of a large dislocation here. Not only are the lowest of the Basement Beds shifted from where they are visible in the Gele west of Pen-y- Graig to a point in the brook east. of Pen-yr-allt (nearly a mile), but the base of the limestone is also shifted more than half a mile, from near Siambr-Wen to the back of the Pen-y-graig or Watch-Tower hill. The steep banks and crags of Castell Cawr from Siambr-Wen to Tan-y-gopa, overlooking the lower country, coimcide with this direction, and make it probable that the fault continues in the same line. Beyond T'an-y-gopa we lose all rocks and features; but a very strong persistent spring at the south end of a drift mound near the coast may possibly indicate its further direction. This spring lies nearly due north of Tan-y-gopa. ; R. H. T. (3.) The Black Limestone. This uppermost subdivision of the Carboniferous Limestone is locally known in the district as the “ Aberdo Limestone,” from the circumstance of certain beds in it possessing, in common with the Liassic limestones of Aberdo (or Aberthaw) in South Wales, the property of forming hydraulic cement. As, however, the same name is applied to any rock possessing the same properties, whatever its age, and as it is not advisable to give the name to both Carboniferous and Liassic limestone, it is proposed to distinguish the subdivision in this district as the Black Limestone. 16 CARBONIFEROUS ROCKS, ~ In this area, and as far south as Holywell, the Black Limestone ~ forms a very constant subdivision. It consists of evenly bedded | black nrgillascais limestones, in beds of 6 to 12 inches in thickness, separated by thin shale partings. The limestone has an earthy texture and a conchoidal fracture, and when freshly broken is black or dark-brown, but soon becomes coated with a fine white or yellowish film composed of an insoluble residue, probably of silica and alumina. Chert-nodules do not occur in ‘limestone ofthis type, though they are abundant in the bands -of limestone of crystalline texture which are occasionally inter- bedded in the series. The diffusion of the silica through the rock, in preference to its segregation into nodules after its usual habit, seems to be connected with the presence of a large proportion of ‘argillaceous matter, a connection which is observable in other areas also.- + = ‘ Under the influence of weather the Black. Limestone breaks up into blocks with clean-cut flat faces and sharp straight edges ; -with further exposure the angles of these blocks shell off, leaving a core of a very regular oval form, which subsequently becomes ‘reduced in size by the peeling off of successive coats. The thin regular bedding, the sharply-cut joints, dark colour, and conchoidal fracture of these heds render them distinguishable at a glance from the ordinary type of limestone. Several quarries have been opened in the Black Limestone in the hill-side above Prestatyn; one of the largest, by the side of the _ igzag road leading to Gwaenysgor, is in a small outlier thrown in bya fault with a westerly down-throw. North-east of this, and at the foot of the hill, the beds roll over in a sharp faulted anti- ‘glinal, the axis of which runs towards Nant-y-mwyn. Near this tine the upper part of the series, consisting of shaly limestone and black splintery shales with 10 Fine sand, about : - 20 Boulder Clay. - e z - 2b ” t 32 - ‘ ‘ as te Sa . ee gaye a4 EO ee eS It-has’ been already stated. that the Boulder Clay of the plain rons up the larger valleys so as.to'be continuous with that of the higher ground. ..This is especially well seen ,in.the case of. the valley at the foot of the Dyserth Castle rock (see Plate). The existing stream-course by which the water from Newmarket and Ffynnon Asaph descends from the hills, occupies a steep-sided limestone gorge which ends in the waterfall. But. a little to the north a narrow but deep tongue of Boulder Clay runs up what appears\to be the pre-glacial line of drainage separating the rock- hills of Crag Heilyn and Dyserth Castle. On attaining the high level of the limestone plateau this Boulder Clay spreads out ina great mass from one to two miles in breadth, and runs for some miles along the high ground to the south, A good section has been opened near the terminus of’ the Prestatyn and Dyserth branch railway, where the clay has, been cut into for a depth of 18 feet without being penetrated, and is seen to be of a deep red colour, and similar to the drift of the plain.. For a long distance southwards this tint continues to predominate; but finally, near Bryn glas, Pwll. halog, Hendre-mynach, and to the south of these spots, passes into a yellow, colour, while the northern boulders are replaced by fragments of Wenlock Shale from the neighbouring Moel Fammau range. The passage from the one Boulder Clay into the other is gradual, nor can it.be said that one under- or over- lies the other. ‘They. were, no doubt, formed contemporaneously, differing only in the source of. supply of material. .Northwards the red tint predominates inthe fongyes of Boulder Clay which \ 32 SUPERFICIAL DEPOSITS. run up the smaller depressions in the limestone plateau towards Gwaenysgor and round the Gop Hill to Axton, but is perhaps due to the clay being composed of ihe’ insoluble residue of limestone. A red tint often prevails in the soil of this rock. Sand and gravel appears at intervals from beneath the clay at these high levels, as in the plain. At Henfryn the Newmarket brook has cut through red Boulder Clay and exposed sand with shell-fragments; and at Hendre-mynach there is a thickness of more than 25 feet of sand seen under a yellow more gravelly clay. But in most cases the sand and gravel'pushes' up through the Boulder Clay in the form of steep mounds or ridges. - A prominent example occurs near the Dyserth Railway terminus (see Plate). At afew yards only from the clay cutting before alluded to, a steep ridge of gravel rises boldly up, and runs up for about 300 yards in a north-east direction along the centre of the valley. The bedding of the gravel is arch-shaped, so as to be roughly parallel to the shape of the ground. The boulders consist’ of about 60 per cent of limestone (the larger blocks about six inches long), the remainder being chiefly Silurian. The coarse gravel is interstratified with bands of grit and sand with shell fragments, and the whole is cemented into irregular blocks by carbonate of lime. : Lge BS Similar gravel-banks occupy the valley again a short distance to the north-east, but with an increase in the proportion of lime- stone boulders to 90 per cent. A sand-pit 500 yards ‘south- south-west of the Gop Farm shows the superposition of the red Boulder Clay on the sand. The clay contains many scratched blocks of limestone ‘about’ one foot long; a large boulder of volcanic ash from the Arenig mountains, and a few shell-fragments. The sand is fine, with gritty patches and veins of loam or clay, and also contains shell-fragments. The bedding of the sand is dis- turbed immediately under the clay.: The steep faces of all these banks are turned towards the west- south-west, and their longer axes are ranged towards the east- north-east. The géneral'trend of all the drift-features on this plateau is in this direction. An esker-like development of sand and gravel appears again at the margin of the. Boulder Olay on the east side of Moel Hiraddug. The ridges consiat of stratified said and gravel with shéll-fragments, but ‘after running -for 400 or 500° yards dié out, leaving the clay in contact with the rock. Seg North of Gwaenysgor a long strip of sand and gravel is shown running over the Black Limestone and Chert outcrops towards Kelston. The line of separation between this deposit and the Boulder Clay is very indefinite. | A. gravelly character invades the clay, and chert-fragments increase in abundance northwards. Finally the gravelly clay. passes into a sand and ‘gravel deposit; which forms characteristic banks near Golden ‘Grove. The same difficulty is met with in drawing: a boundary between the sand and gravel and Boulder Clay about Axton, though the former preserves in the main its habit of rising into GLACIAL BEDS. 33 banks and hillocks. One of these occurs near Pant-glas, with an axis running about E. 10° S., and nearly parallel to the valley. A smaller one on the opposite of the valley, and 500 yards north- west of Ty-draw, runs from the hill side in a direction that would take it across the valley, though as a general rule the gravel- banks have their longer axes ranged in the direction of the valley in which they are situated. Scattered over the country, over the drift-covered areas and the bare hill-tops alike, there occur large erratic blocks. Though scarce in the area now specially under consideration, they become exceedingly abundant further south, where they are found up to an altitude of more than 1,400 feet. A very large proportion of these has been derived from the felspathic volcanic series in the Bala Beds of the Snowdon and ‘Arenig groups of mountains, and have therefore travelled in an easi-north- -easterly direction. One such, measuring 5 x4%3 feet, occurs-on Cwm Mountain at a height of about 830 feet above Ordnance Datum ; another, of doubtful. source, measuring 9x6 x5 feet, lies in the bed of the stream near Hendre-bach (Hendre mynach on the one-inch map) ; a third, possibly from the Bala Beds, measuring 3x14x1 feet, lies on the bank of the stream above Hendre fawr, the elevation of these being between 500 and 600 feet. A smaller boulder is imbedded in the side of the road at Pentre near Newmarket. Others occur in the Vale of Clwyd, and scattered over the Denbighshire hills to the west. These felspathic boulders are confined : generally - to the areas in which Drifts of WERLEIA derivation occur. Bones have been found in unusual quantity in ‘lis Drift of Talargoch, principally owing to. the vast extent of gravel that was tunnelled through in different directions to get the “gravel-ore. Buckland says, “the remains of ox and stag are found at present, and in 1815 a pair of stag’s horns were discovered at 60 yards below the surface... ... Horns, teeth, and bones are found in it [the gravel], at from 40 to 70 yards from the surface, and also at the bottom of the gravel, in immediate contact with the subjacent limestone rock.”* Mr. Trimmer ‘adds that two bones found in a bed of gravel at 63 yards from the surface, accompanied by marine shells, had been presented by Mr. 'T. HOS. HARRISON, to the Caernarvon Museum. These were pronounced by Dr. Buckianp to be the astralagus of a large, and the humerus of a small deer. At the time of Mr. TRimMEr’s visit the workings in the gravel had been discontinued, but the workmen: “ spoke of horns of deer, bones, shells, and timber, as having been found ;” and: the superintendent of the mine gave him” a: specimen of Purpura lapillus, two of which had lately 3 veen found in sinking a shaft at the eastern end of the works. These happened to have been the only specimens of whole shells observed ; but the miners peeeibed a bed of gravel near the western end as having * Reliquie Diluviane, p. 178. 34 SUPERFICIAL DEPOSITS. heen met with many years ago, abounding with‘ Cockle-shells, all in fragments.”*. One of the bones from Talargoch, now preserved in the Museum of the Chester Society of Natural Science, has been identified by Pror. W. Boyp Dawkins as the left ilium of a bison. . It may be mentioned here also. that. pieces of bones belonging to rhinoceras, mammoth, reindeer, and horse have been recently discovered by Dr. Hicxs in the Ffynnon Beuno and Cae Gwyn Caves half a mile south of Tremeirchion (about two and a half miles south,of the margin of this Quarter-Sheet.)t ‘The bones are believed by Dr. Hicks to have been introduced into the caves before the great, submergence which led to the deposition of the high-level marine sands and gravels, and therefore also before the deposition of the great upper Boulder deposits of this area. In the case of the famous Cefn Cave also there was evidence of the ossiferous deposits being earlier than a part at least of the Glacial Deposits. A full, description of the Tremeirchion and Cefn caves is reserved for the Memoir on the Quarter-Sheet in which they occur (79 S.W.), but it will be seen, from what.has been said above, that there is reason for believing the bones found in them to be of the same age as those found beneath the Drift at. Talargoch. Shell-fragments are of common occurrence in all the sands and gravels and in the red Boulder Clay, and may be found in any of the. brick-pits about Rhyl, Abergele and Colwyn, Cardium edule being the most abundant. The specimens are always waterworn, and generally fragmentary. *. oe ne _ On the west, of the Clwyd the red Boulder Clay runs along the coast, forming the drift-terrace previously alluded to, The form of the terrace is especially well seen between Abergele and Llandulas, The clay as seen in the coast section and brick-pits near Abergele is a tough red clay with few boulders. Inland it sends long tongues up the valleys which separate the limestone hills, and mostly mark lines of fault. West of Llan- dulas the terrace becomes very narrow, and finally ends against the rock-promontory of Craig. On the east side of this promontory the following remarkable section is exposed in the sea-cliff. _ Against the nearly vertical eastern face of the point is banked a stratified breccia, composed exclusively of sharply angular fragments of limestone, with a few blocks of 8 or 9 feet in length. The deposit at first sight resembles :a talus, but .the slope of the bedding is at'too gentle an angle, namely from 10° to 20°, for this mode of production. The thickness of breccia seen in the cliff is about 80 feet, and it sinks eastwards to the level of .the beach in * On the Diluvial or Northern Drift of the Eastern and Western Sides of the Cambrian Chain. By JosHusa Trimmer, Dublin, 1838, pp, 32, 33. t On some recent researches in Bone Caves in North Wales. Proc. Geol. Assoc. vol. ix., No. 1, p. 13 1885. ee es ‘ ei ages ea Physical Geology and Geography of Great Britain. 5th Ed. p. 469; reat mad _ GLACIAL BEDS. 35 about 150 yards. The breccia is overlain by 8 or 9 feet of stratified pebble gravel and sand, and this again by tough. choco- late-coloured Boulder Clay, with numerous well-scratched boulders, which are in_the proportions of about, 80 per cent. of Silurian and 20 per cent. of-limestone a-short -distance from the point and about 50 per cent. of each farther away.* ‘From the beach the red clay rapidly mounts the less steep parts of the brow of limestone, and’ runs up the dip slopes to Llysfaen and Ty mawr, becoming. more gravelly at the greater height. Taking advantage also of the deep gorge in the limestone occupied by the Dulas, it sends an arm inland as far Rhyd-y-foel (Foel-fach on the one-inch map), where it is succeeded abruptly by a grey and yellow drift composed exclusively of the local ‘Silorian rock. The foel which gives its name to the locality is a conspicuous little hill projecting into the valley, and composed of a pebble-gravel of Wenlock Shale, banked up on a projecting shoulder of limestone. Southwards this gravel appears to pass into a more clayey drift composed of similar materials. | On the top of the point of Craig (or Penmaen) there are two small patches of Boulder Clay filling hollows in the limestone. _In'the westernmost of the two, the Drift reaches a thickness of 20 feet, as seen in section at the edge of. the cliff, and rests upon a glaciated surface of rock (see p. 39). ‘Crossing the promontory of Craig into Colwyn Bay, we find the red Boulder Clay banked up against the limestone ‘cliff without the intervention of any breccia or beds. of gravel. “Further west about old Colwyn and the dingle at Min-y-don it is concealed, or perhaps replaced, by a rudely stratified gravelly deposit made up entirely of Wenlock Shale fragments. This gravelly deposit is seen in the dingles to extend to some seven or eight hundred yards west of Colwyn Bay station, finally thinning out on the top of the red clay. The great :ballast-pit at Colwyn Bay Station shows that this Silurian drift is in part contemporaneous with the red Boulder Clay, the two alternating or being mixed up together. The following: sections ‘prove this, and will serve to illustrate the rapid horizontal changes in the deposits. Colwyn Bay Sand and Gravel Pit. North end of the pit. ye Feet. Silurian drift, in part pebbly and stratified (Wenlock Shale only) 10 Fine sand - - - . - : - - 15+ ‘ 25 * Mrs. T. McK. Huaues informs me that a skull of Bos longifrons and of Cervus ae (now preserved in the Cambrian Ton at Pensarn) are said to have been ound at a depth of 18 feet in digging clay for making the railway embankment, and that there is ‘also in the same Inn a fine pair of Red Deer antlers, which was washed out of the clay on the shore in a storm. There are barnacles (Balanus) on one of the highest tynes, showing that it had projected though the clay for some time. It is probable that these skulls and horus became embedded in the clay in consequence ofa landslip. The undercliff about Llandulas Station consists almost entirely of slipped masses of Boulder Clay. 36 SUPERFICIAL DEPOSITS. South-west side. Silurian drift, as above - E : 3 . = Red clay with few stones - - - = 2S = 9 Silurian pebble-pravel - av e - A - 20 Fine sand - - ‘a 3 s - me Es 33 South side, towards the east end. Silurian drift, gravelly, and mixed up with and containing masses of the red clay of the preceding section - - 20+ South-east corner. Silurian drift, white loamy clay, with pockets or irregular bands _ of pebbly drift - fs é a - AB . Stratified loam and fine gravel = - - 2-6 Red clay bent into sharp folds, and thinning out to the north - 0—5 Silurian gravelly drift, with uneven surface -- - - 10+ a7 . North-east corner. Silurian drift, loam and gravel as above - - - - 6 Silurian gravel goss co: - - - - - 20 Fine sand - - - - . - = = at 34 Further along the beach westwards red clay with pockets of sand, and from’ 6 to 12 feet in thickness, is seen resting on fine sand with bands of pebble-gravel, the uppermost Silurian’ drift being exposed here and there at the top of the cliffas faras a dingle 400 yards north-west of Colwyn Bay Hotel. The bed of fine sand with pebbly bands is seen in this part of the bay tu rest on the gently undulating surface of a mass of stiff blue clay full of intensely glaciated Silurian boulders, many of large size. The beds are much obscured by the slipping of the sii but the following sections could be made out. 100 to 200 yards east of Colwyn Bay Hotel. - 4 : Feet, Red gritty clay with pockets of sand - - - - 6to12 Sand with pebble-gravel - . — - a S 124 100 yards north-west of the Hotel. Yellow loam = - - - - - - 2 Silurian gravelly drift - - - * : = % 4 Red clay, about - -. - : - . - 6+010 Sai - - about 25 nd Blue clay, full of gratchea Siiveian bedlders, seen in the fore-shore below the Hotel - = - = : GLACIAL BEDS. 37 400 yards north-west of the Hotel. 4 tol Yellow loam (in part reddish), thinning from - - - Silurian eravelly drift do. do. - - - 3t00 Red clay - - ie . z 8 Sand .- 7 é jm = os 3 3 104 500 yan Oren cet of the Hotel. Red clay, gritty - - - - - 7 5 Sand - . - - - S 2 Tough red clay - - - - - - - 4. Sand - § - - - - - - - 144+ At the Bath House (700 yards north-west of the Hotel). Red clay, gritty - - - - 6 Sand with bands of te red clay - os - - - 25 Blue clay, full of scratched Silurian boulders - - - 4+ 200 vine south of A.ber-hod (150 yards north of the preceding section). Red age gritty” - - - 6-9 . Tough red clay, and sand i in thin bands eg ts 4 ga apparently aaepnfomeply on E 3 - - : - - - 1 Stiff blue clay as above - - - - - 3+ North of this point the red gritty clay alone is seen in the low cliff which extends to the alluvium of Glan-y-mor. But on cross- ing to the outlying hill of Drift, which this alluvium insulates, we find a cliff rising to about 30 feet in its highest part, and composed of — ; Feet. Red clay, sometimes nearly stoneless , - 4t010 Blue clay, with large munenecly, glaciated Silurian and lime- } 9+ stone boulders - - - . . The surface of the ‘blue clay rises gently towards the centre of - the hill, the red clay thinning out correspondingly. The junction between the two is usually sharp and conspicuous, but there is at times a passage, as though the materials had been mixed for a thickness of one or two feet..: The Boulder Clay cliff which com- mences within the western sid of the Map, shows a similar sequence ‘‘ with the intercalation here and thére of 2 to 6 feet of sand and -- shingle with shell fragments between the two clays. The limits of these various members of the Drift were found to be very obscure inland.. The uppermost ‘yellow loam and gravelly Silurian drift is confined to the neighbourhood of the cliff about ‘Colwyn Bay Station and Hotel; and in the brick-pits along the Conway road ‘the red clay is: found resting on a sand that is doubtless continuous with that of the cliff; the sand with a trace of -- red clay over. it is seen in an old pit near Pwll-y-crochan-isaf. 38 SUPERFICIAL DEPOSITS Towards Old Colwyn the gravelly Silurian drift, with every appearance of being mixed up ) with the red clay (as indicated in the ballast pit), extends further inland, and appears to merge into the blue clay-drift that runs up .the valleys. On the south-west and south-east sides‘of Old Colwyn there is a considerable’ develop- ‘ment of sand, possibly'a continuation of the bed seen at Colwyn Bay Station. -The sand is fine and stratified with a little gravel aud a few thin geams of red clay, and forms small mounds or eskers. Towards the west the limit of the red clay runs from near the brick-pits mentioned above, “by Bryn Hurian and’ a Eurian, towards Ty’n-rhiw. The valleys which run southwards into the Silurian ‘hia are occupied by a tough blue Till full of scratched Silurian boulders of local origin,. with far-travelled | blocks of..felstone from the Snowdon range. This Till is exposed i in many of the ravines to a depth of 30 to 50 feet; and runs up to a high level on the gentler slopes of the hills. The general direction of transport - appears to have been about south-south-west to north-north-east, as indicated by the presence of the felstone boulders, and the appearance of limestone boulders:in the local ,basement clay of the coast to the north-north-east of Bryn Eurian._, The various glacial beds seen in Colwyn Bay and the neigh- bourhood may be sumiarised as follows :— Local drift ; yellow loam and rudely stratified. Silurian gravelly drift, resting upon or in part mixed up with— Far-travelled-red Boulder-Clay. - Fine sand with a little shingle. Local drift; a very wag ‘blue clay packed with scratched stones. 4 GuactaL STRia. The following. instances, of striated rock surfaces have been observed during the Survey of this Quarter-sheet, qd ) ee 50 yards south of Pen-yr-Allt, near Gels yacoes ; height above Ordnance Datum, 660-feet.. The surface of the rock is protected by a little tough red Boulder Clay, and is well polished and marked with short scratches, fairly constant in the direction N. 5° W. . The direction of flow was probably from southwards; the ground slopes towards the south-west. (2) Graig-fawr, near Dyserth (see Plate) 3- height above Ordnance Datum, 160 feet. The strize.occur on a pro- ‘jecting shoulder of limestone at the foot of .a: “very: steep rocky slope facing west ; they sweep round the shoulder horizontally. The direction of flow must have been from. north. to south, the projections of the rock being smoothed and striated on the sidés facing north. (3.) Moel Hiraddug, near Dyserth ; height above Ordnance Datum, 750 feet. . The strize occur on a terrace of lime- GLACIAL BEDS, 39 stone on the east side of the hill, the ground sloping to “the east-north-east + they are covered by a little gravelly ‘| Boulder Clay. Direction N.E. ; (4.) *Cwm Mountain; height above Ordnance Datum, 990 feet. The strize occur in a driftless area 200 yards to the east of the highest point of the hill, and may be ex- posed by removing the turf. They vary in direction / from N,E. to E. 33°.N. (5.) Craig Cliff, near’ Llandulas Station; height above Ord- "nance Datum, about 70 feet :— — Ss (a.) In a small hollow leading up to the air-shaft of ’ the tunnel, and filled with drift. Direction N. 10° EB. * (o.) On a nearly horizontal surface of limestone a _ few yards to the east of the hollow mentioned above. Direction N.E. (6.) Craig Tunnel, near Llandulas Station; height above Ord- nance Datum, 130 feet. The brow of limestone forming the roof of the east entrance of the tunnel is well glaciated in the direction N. 10° W. (7.) Quarry on the sonth side of the high road above Llandulas Station ; height above Ordnance Datum, about 270 feet. The strize were exposed by the clearing away of about ‘three feet of red Boulder Clay from a broad surface of limestone ; they were long, and not perfectly straight, in a direction N. 30° E. The ground slopes to the north, towards the adjoining cliff. (8.) tCefn-yr-ogof, on the east side of the valley of the Dulas; height above Ordnance Datum, about 230 feet. Direction ‘of the strize N. 12° E. The connection between the direction of the striz and of the drift-transport is very noticeable along the Welsh border. The north-easterly trend of the strie on Cwm Mountain, Moel Hiraddug, and the north coast is generally maintained by the strie near Holywell, Mold, Minera, and Llangollen; and through- out these regions the transportal of the drift-materials has been towards the north-east or.¢ast. This Quarter-Sheet includes a con- siderable length. of the irregular boundary which separates: the local Welsh Drift, from the west from the far-travelled northern Drift as previously described, and in the striz of Graig-fawr, which are in the area of the lattur, contains an interesting example of the corresponding change in the direction of the glaciation., A further connection between the strie and Drift is found in the fact that the glaciated surfaces always occur in conjunction with the Boulder Clays in preference to the stratified sands and gravels; and the Boulder Clays, alone of the drift deposits, show such evidence of the action of ice, as want of stratification, the * Pointed out to Mn. R. H. Trppzman by Prog. T. McK. Huaues. J Observed by Mr. R. H. Tiwpeman. 40 SUPERFICIAL DEPOSITS. presence of scratched stones, and the mechanical disturbance of the underlying beds. It seems reasonable, therefore, to attribute the striation of the rock-surface and the distribution of the Boulder Clays to the same agent, probably floating ice. Post-GLactaL Bens. Caleareous Tufa, A large mass of this: material overspreads the slopes above Felin Nant, near Prestatyn. It was formed by the. overflow of a spring, by which the mill was formerly worked, but which has now been drained by the mining operations. The tufa consists of white amorphous carbonate of lime, encrusting twigs, snail- shells, and other ‘fragments mixed with sand, and is sometimes hard enough to be dug out in blocks for ornamental rockeries. Another smaller patch occurs in the field between the railway and the farm. Cefn-yr-ogof, three-quarters of a mile east of Liandulas.* Peat and Alluvium. These deposits occupy a large area, bordering the rivers Gele and Clwyd, and the sea-coast between Rhyl and Prestatyn. Near the estuary of Clwyd the upper layers consist, of alternations of tidal silt and “slutch” overlying or alternating with cand, and, towards Prestatyn, of fresh-water marsh-clay and peat, occupying the sites of shallow meres enclosed by dunes and low banks of blown sand. Below these recent beds there occur several beds of peat ranging down to about 40 feet below Ordnance Datum. Our information concerning these is derived chiefly from the boreholes, which are described below. os The Foryd borehole (given in full on p. 25) commenced at 12 feet above Ordnance Datum, and reached the base of the alluvial deposits at 46 feet 4 inches below this datum, giving a total thickness of 58 feet 4 inches. The following beds were passed through :— . Ft. ins. Ft. ins. Surface of ground - - 12 0 above Ordnance Datum. Clay » 2@ Sand - - 19 0 Gravel - - 4 0 Mud and clay - 16 6 Turf [peat] - - 6 Blue clay - - 10 4 Turf [peat] - - 16. Blue clay - : 1°0 Gravel - - ‘3 «6 BS 4 46 4below ,, me * Larger deposits of calcareous tufa are found in two of the valleys near Caerwys, in Quarter-sheet 79 8.E. POST-GLACIAL BEDS, 4] Two boreholes were put down at the Rhyl Town Hall for the purpose of testing the ground. No. 1, on the south side, proved the following beds :—* Ft. ins. Ft. ins. Surface of ground - - - 20 0 above Ordnance Datum. Made ground about 3 0 Yellow sand, damp. in places - - 6 7 Blue clay, with traces of peatin places- 5 5 Strong peat, dark at top, light and mottled below, with branches of trees and parts of trunks - - 3 0 Strong blueclay -. 2 Q+ 20 0 0 0 a> 33 3? Peat was also met with in the sewer in the Marsh Road, and is now exposed to view in the bottoms of the brick-pits in the marsh lying on the south side of the town. The section here shows three to four feet of blue clay with Scrobicularia piperata, resting on peat with large tree-trunks, The level of the top of the peat- bed is about nine feet above Ordnance Datum. -Peat-beds may also be seen cropping out in the foreshore between Rhyl and Aber- gele, where they have been much bored into by Pholas.t Mrs. T. McK. Hugues remarks also that “in the marsh land bordered by the sand-dunes north of Prestatyn, at the edge of the water in some of the gutters, quantities of very large shells of Scrobri- cularia piperata are found sticking up in their original position. The valves are usually together, though the ligament has often perished, and the shells are much stained and encrusted with calcareous mud. It seems as if the stream had cut down to the bed in which they lived under former conditions of the district. On the shore side of the dunes there are patches of clay much bored into -by Pholas candida. Pieces of blackened wood and hazel-nuts, some of the latter apparently gnawed by squirrels or some other small rodents, are found along the shore, and are probably washed out of patches of peat which are seen here and there.” The Scrobicularia piperata being a marine or estuarine shell, it would appear that the clays in which its occurrence has been noted above have been laid down by the tide, at a time when the. sea had access to channels and low-lying hollows which are now enclosed by sand-hills or protected by artificial banks. A section, similar to that at Rhyl, occurs at the north-west _end of Colwyn Bay, where the low-lying alluvium of Morfa- Llandrillo abuts upon the shore at Rhos. The beds have been * This information was supplied by Mr. A. Bett, C.E. { Mr. W. Suonz states that Pholas may be seen living in the peat-beds at low spring-tides, 42 SUPERFIOCTAL- DEPOSITS. described by Mr. H. F. Hatt, as follows in brief* :—Two beds of peat occur about six feet apart, and six and twelve. feet respec- tively below high-water mark. ‘The upper bed is about one foot thick, and consists of peat with tree-roots, and traversed by branches and trunks. The’ roots: penetrate an underlying blue clay, and the trunks lie in all directions as they fell; one was found to be fully 50 feet in length, and a stump ip situ was three feet in diameter. This upper bed is underlain « by six: feet. of blue clay with a few pebbles, below which occurs the second peat-bed similar to the first. The trees are believed to be'oak and pine. The peat-beds were again met with in a well sunk for the new Rhos Abbey hotel, which proved the following section :-— - 3 Feet. Sandy gravel - -— - 3 Solid blue clay - ~ - 15 Peat-bed, ‘with treed, dbout - 1 Blue clay - - - 4 Peat- bed, with trees om, - 1 Fine clay mixed with sand - 8 27 This: strip’ of aig insulates the Boulder Clay hill on w hich Capel St. Trillo stands, and is continuous with the broad marsh that comes down from Llangwystenin. The marsh is in part below the level of high spring-tides, and is protected by an artificial bank and sluice. In the absence of such protection, and of the alluvial deposits that have raised the level of the land, there would probably be free communication by this valley between the sea and the river Conway, as has been suggested in a paper by Mr. C. R. Hatxi.t In this paper Mr. Hau refers toa tradition of the Welsh thai the coast from Anglesea to Flintshire was formerly fringed by a fertile plain called © Morfa Rhianedd,” which was destroyed by sea and land floods ¢ occurring coincidently in A.D. 331. The residence of Helig, the owner of these. lands, was situated, according to tradition, on the shoal known as Llys Helig ab Glanawg; at'a distance from Gogarth-of nearly five miles, and from: the Dwygyfylchi shote of two miles, In 1864: Mr, HAux, in company with the Rev. R. Paxry, visited the shoal at low tide, and found what he believed to be traces of the founda- tions of a house consisting'of three wings enclosing : a counhyard, and the remnant of the base of a round tower. An epitaph in Abergele churchyard is popularly supposed to constitute further evidence of loss of land on this coast. ' The subjoined copy of the epitaph, and note upon it, are furnished by Mr. TIDDEMAN:— » Prete : tH * Notice of Sehwieneet Forests at hon near a. _Proe. Liverpool Geol. Soc. by Bess. 7, p. 81, 1865-66. t Some Conjectural Hints towards determining the Ancient Coast-line of North Wales, between the River Dee and the Island of Anglesea.. Geol. Mag., vol.ii. p.'78, and Proc. Liverpool Geol. Soc., Sess, 6, p. 7, 1864. POST-GLACIAL BEDS. A3 Built into the wall of Abergele churchyard is a gravestone bearing the following inscription :— . “Yma mae’n gorwedd ‘Yn monwent Mihangel Gwr oedd a’i annedd Dair milltir yn y gogledd.” which may thus be translated :— “Here there reposes In the churchyard of Michael A man who had dwelling Three miles to the northward.” The characters would lead one to suppose that it may date from the beginning of the ‘17th century, but unfortunately no date has been placed upon the stone. Tradition says that it is a copy of a much older stone. Close by in the wall is another stone . with three letters on it, which is considered by some to be part of the original, but this has not been proved to be the case. : The site is now less than a mile from the sea. The obvious inference intended to be drawn from the wording of the inscription is that during the lifetime of the person here buried a great sacrifice of land to the ravages of the sea had occurred. Evidently the site alluded to was no longer dry land. Had it been, the name of the place would have been given, or it would not have been referred to in so mysterious a manner. Both the name of the man and of the place of his dwelling are suppressed in order to bring into prominence the fact of the latter having been three miles to the north. Well prepared as we may be to admit the destruction of the land by the sea, we must not, I think, lay too much stress upon this epitaph. It is quite possible that it may cover merely the grave of an unknown mariner who was washed ashore, and whose “dwelling” was wrecked at that distance from Abergele. Such semi-jocular epitaphs under like circumstances are not uncommon on our coasts. BR. He T. The evidence of the peat-beds described above seems to prove that the coast has lost considerably in level since the close of the Glacial Epoch. ‘The level of the Jowest marshes of the present day that are not liable to be overflowed by the tide (including those that are artificially protected) ranges from 12 to 15 feet above Ordnance Datum. ‘he peat-beds of Rhos and of the brick-pits and bore-hole in Rhyl, which seem to be old forest- grown land-surfaces, occur at or but little above Ordance Datum, and seem to mark the last stages in the process of submergence, before the coast assumed its present level. The level of the ancient lands referred to in the Welsh tradition, if they ever existed, may be indicated by cne of these beds. ‘lhe position of the alleged foundations of the Llys Helig would indicate a loss of about 25 feet in level, supposing them to have been walls. orginally built above the level of high-tide. Evidence of A 17240. D 44 SUPERFICIAL DEPOSITS. oscillations of level are found also on the Cheshire* and Lancas- shire coasis.t . Binizn Sand, ; The line of dunes is narrow from Abergele to the Clwyd, and has to be artificially made up; but east of this river the sand spreads inland on to the gentle slopes of Boulder Clay south-east of Rhyl, and towards Prestatyn rises in dunes 40 or 50 feet above the sea, forming an ample protection to the broad marsh behind. The sand is carried along the shore from west to east by the prevailing winds and by the flood tides, a fact clearly indicated by the eastward trend of the river channels on entering the tidal region. Off Prestatyn the growth of sand-banks is being encouraged by intercepting the drift by lines of stakes and wattles. Further east the sand has been arranged by the wind in low ridges running from the north-west, and enclosing shallow marshy or peaty flats. 7 = * Dz Rance, Geology of the Country around Prescot (Geol. Survey Memoi 3rd Edition, p. 31; Froe. Liverpool Geol. Soc., Sess. 10, . 37 (Porms), Conk Mag., vol. x. (Dr Rancr and Mrtiarp Rzane), } Dz Rance, Superficial Deposits of S.W. Lancashire (Geol. Survey Memoir). ‘ ECONOMIC GEOLOGY. “46 CHAPTER III. ECONOMIC GEOLOGY. MINING. The following ores have ‘been worked in the Carboniferous rocks of this district. Galena, in part argentiferous (sulphide of lead with silver): Blende (sulphide of zinc).. Calamine or “ Coke ” (carbonate of zinc). Heematite (oxide of iron). Heematite with nickel and cobalt. Hematite with copper. Pyrolusite (dioxide or black oxide of manganese). Galena, Blende, and Calamine are found only in the upper or middle beds of the Limestone and in the Chert beds (Millstone Grit). Hematite is generally confined to the lower beds of the Limestone and the Basement Beds. Manganese ore occurs in the Chert and in the Basement Beds. LEAD AND ZINC ORES. These ores are usually found in close connection in the same vein, the zinc ores and the argentiferous galena, however, being almost invariably confined to the east and west veins, while a non-argentiférous galena\ with minute traces of copper is ‘found in the north and south cross-courses. In this part of Flintshire the veins do not so readily fall into the two systems as in the neighbourhood of Holywell and Mold, where the rule is well established. The Talargoch veins, for example, which are essentially of the east and west type‘in their contents, run nearly north-east and south-west. Calamine, and more rarely “ white lead” (carbonate of lead) are found in the shallower parts of the veins, and pass downwards into blende and galena respectively; they are probably formed by the weathering of these ores. The silver occurs in the galena in proportions ranging up to 12 (or rarely 14) ounces per ton. It is extracted by the zinc process at Bagillt and Llanerch-y-mor, and is found to repay the cost when exceeding 3 ounces per ton. The principal mines in this area are the Talargoch and the Talacre. There have also been trials made with partial success at Kelston, Golden Grove, Volcnant, Nant-y-mwyn, Gwaenysgor, Dyserth, and near Abergele. D2 46 ° ECONOMIC GEOLOGY. Talargoch Lead Mine. (See Plate and Sections.) This great mine is said to have been worked continuously from a very early period. Tuomas Prnnant states, “I am in possession of a little wedge five inches and a quarter long, presented to me by the late Mr. Smepuey, of Bagillt Hall, discovered in working the deep fissures of Dalar Goch rock im the parish of Diserth in this county. This little instrument affords a proof of its antiquity by being almost incrusted with lead ore. It had probably lain in the course of some subterranean stream which had brought along with it leaden particles and deposited them in the iron.”* It is believed that lead was mined in Flintshire during. the Roman occupation,t and that this was one of the mines in operation at that period. But though the strings which run down the rocky sides of Graig-fawr would be among the first to attract attention, it seems. hardly likely that the deep-seated veins which have yielded the bulk of the ore in modern times should have been reached through the thick water-bearing Drift which covers them. In this case, as in most others, there is little more’ than tradition as to the age of the first workings. ; . BS i It has already been shown thatthe beds of limestone sweep round Graig-fawr, dipping to the north and north-west until they are cut off by the great Vale of Clwyd fault. The veins, having a general north-easterly direction, traverse the beds at an acute angle, so as to pass gradually from the massive white limestone of the south-west end of the mine into more thinly-bedded lime- stone, and finally through the Black Limestone series of the north-east end, where they are cut off by the shale as previously described (p. 21); but. their direction so nearly coincides. with the strike of the thin-bedded limestones that the vein-products are often found occupying the position of a bed ‘between two highly inclined bedding-planes marked with slickenside. . ‘The veins are three in number, and are known as Panton’s Vein on the north-west, the Talargoch Vein in the centre, and the Cae-llys, Coetia-llys, or South Joint to the south-east. They are roughly. parallel, and all hade or “underlie” to the north-west. The direction. and hade of. the Talargoch Vein at various points are as follows :—At the south-west end, N. 22°E., at 1 in 2; under the high road, N. 34° E.; near the office, N. 50° Eat lin 7; near the Methodist chapel and, at the Mostyn shaft, N. 50° E.., * The History of the Parishes of Whiteford and Holywell, 1796, p. 122. ‘he .t “Near Norton [Cheshire] there have teen many pieces ‘or pigs of lead dug up of an oblong form: the upper part of some was thus inscribed. Imp. Vesp. vii. T. Imp: V. Coss. | On others was this inscription. Imp. Domit. Aug. Ger. De. Ceang.” England Displayed, vol. ii., p. 72. ; of : A pig of lead, bearing an inscription which commences with the word Caesar, but of which the rest is obliterated, was found in Commonhall St., Chester, and is now preserved in the Museum of the Chester Archeological Society. Another, found near Hoole Lane in making the canal, bears the name Vespasian, and is now at Eaton Hall. Lead was used by the Ronians, as is known by the discovery of the remains in Chester, for their funeral urns, and it is believed also for their salt-pans at North- wich, as well as for many other purposes. . MINING. 47 at 1 in 2; and at the north-east end, N. 50° E.,at 1in 5. The direction of the South Joint varies from about E. 8° N. in its southern part to E. 41° N. towards the north, the hade being about 1 in 3. It has been worked for a distance of about 200 yards southwards from the shale-fault which forms the northern boundary of the mine. Panton’s Vein first appears a few yards north of Walker’s shaft, and runs N. 30° E., curving to N. 50° E. on approaching the shale-fault. The Talargoch Vein alone runs the whole length of the mine, a distance of about 1,400 yards. _In former days a large quantity of cre was obtained from the base of the Drift. It was’found in large water-worn lumps distributed over the surface of the rock, and was obtained by driving galleries in various directions through the gravel, which had been drained of water by the pumping in the mine.* Ore found in this manner is known as Gravel or Round Ore; it commonly occurs near the outcrop of a productive vein, and forms a useful indication to the miner. It may be supposed that as the rock containing the vein perished and was washed away, the lumps of ore remained behind, owing to their higher specific gravity. The workings in the Talargoch vein have been carried toa depth of 360 yards from the surface at the north end, and in the South Joint and Panton’s. vein to about half this depth.t In 1881 a lode rich im blende, but with little lead, was being worked at the former depth in the Talargoch vein, while to the south pockets and “ flats” connected with the same vein, at’ 220 yards depth were yielding large quantities cf lead with little or no blende. The replacement of the lead by blende in the depth preved unfortunate for the mine. The shallower parts of the veins mentioned above may’ be considered exhausted. As shown in fhe accompanying section (Plate, Section No. 2) the white limestone of the south end yielded vast quantities of ore, while the Black Limestone also was highly productive, though in other mines it has generally been found to be barren. At the south end of the mine the Talargoch vein splits up into and is intersected by numerous small strings from which a great quantity of ore has been raised. Some of them may be seen running up the sides of Graig-fawr and the rock on which Dyserth Castle stands. Their direction varies from E. 25° N. to about E. 50° N.; but one of the strongest, known as the China Rake, runs E, 10° S., intersecting and cutting off the others. It obtains its name from the fact of its being filled with a fine silicious vein- stuff, which has been used in the Staffordshire Potteries. The deposit in its unweathered state resembles granular: quartz, but readily weathers into a loose pure white sand. It often contains lumps of cale-spar and galena, and is clearly a chemically formed vein-product, not to be confounded with the chert-breccia which “ For an account of the bones found during these operations, see p. 33. + Masses are. said to have been found so large as to have yielded 80 tons of ore.—TRIMMER : On the Diluvial or Northern Drift of the Eastern and Western sides of the Cambrian Chain, p. 33. t Plans and sections of the mine are deposited in the Home Office, Whitehall. 48 ECONOMIC GEOLOGY. is fouid in the veins at the north end of the mine (p. 21). Silicious vein-stuff is commonly found in the Flintshire veins, especially in the beds which lie next below the chert, but not often in such purity. From the China Rake the silica runs down towards the Clive shaft along a string from which it is occasionally raised at the present time.* , It may be mentioned here. that a combustible pitch was found to issue from a fissure in the south end of the 180 yards level in the South Joint; and M. Morssmner- remarked a banded red and white deposit from the water in this level, consisting, as he believed, of alternate layers of sulphur and oxide of iron.t In some-of these strings Calamine, locally known as “ Coke,” t was formerly worked, and one of the day-levels in Graig-fawr is still. called the Coke Hole. 'This mineral used to be abundant near Holywell, where it has been worked since the year 1740. It was found in the shallow parts of the veins only. The total production of galena fromthe Talargoch mine’ in the years 1845-84 inclusive amounted to 57,752 tons, yielding 43,821 tons of metallic lead (or about 75 8 per cent.), and an average of 94 ounces of silver to the ton. The yield of blende in the years 1855-84 inclusive, was 49,810 tons.|| The average yearly sale for the three years 1880-82 was stated to be 1,035 tons of lead, and 3,041 tons of blende, in the advertisements offering the mine for sale in the year 1883. But in the year 1883, though 2,910 tons of blende were raised, the production of lead fell to 391 tons, and in May 1884 the pumping was abandoned, and the mine allowed to fill with water up to the day-level. The operations are now confined to the redressing of the old rubbish heaps. The Talacre Mine. Two metalliferous veins, known as the Talacre or Spar Vein and the Joint-y-clawdd, respectively, run through the top beds of the Chertat Gronant. The Talacre Vein isa fault with a small down-throw to the south, and underlying therefore in this direction. It has been worked of late years principally at the east end, near the fault. which throws the Chert against Lower Coal Measures, _ Westwards it has been followed as far as the Sycamore Shaft, near the Calvinistic Methodist Chapel, and is believed to run through * Mr. W. Smiru, Secretary of the late Company, states that the value of the white sand.would be about 10s. per ton, but that thereis no commercial demand for it. + Mémoire sur le gisément du Minerai de plomb dans le Caleaire Carbonifére du Flintshire. Annales des Mines, ser. 5 tome xi. p. 851. Paris, 1857. t There is some uncertainty as to the origin and spelling of this name. It may be derived from the friable and cinder-like appearance of the mineral. It must not be confounded with Cawk, a popular name for Barytes. , § Pennant remarks that though the uses of Calamine were known to the Romans, the knowledge of it in after ages was long lost. . .) .° Our country abounds with it, but till within these 60 years we were so ignorant of the value as to mend our roads with it; which have of late years been turned up in a hundred places. most successfully to recover the lost wealth.” History of Whiteford and Holywell. é || Mineral Statistics of the United Kingdom, by R. Hunt, MINING. 49 some old surface-workings by the side of the road leading to Golden Grove. The direction of the vein at the east end is a little south of east, curving by the Engine Shaft to E. 10° N., and near these old workings to about E.20° N. The Joint~y-clawdd is a vertical string running through the Pentre Chert quarry, which intersects the old workings, and thence along the edge of the plantation, passing 90 yards south of the Engine Shaft to the smithy, near. which it is said to join the Talacre Vein. The old trenches along the joint are still open for about 250 yards, and provide the reason for the name (Clawd, Angi. ditch); they show’ the junction of the Chert with the overlying shales as before mentioned. The general direction of the Joint-y-clawdd is E. 20° N. A similar joint in the same beds, and bearing N. 40° E., has been worked open-cast by the side of the road near Kelston Farm. } The workings on these veins are all in the Chert Beds, which are of great. thickness, the lowest level on the Talacre Vein being at 105 yards depth. At the time of my survey the mine was inactive, and the following description is taken from the paper by M. L. Moissener (op. cit.) The hade of the veins was 2 in 3 at the top, and 1 in 1 lower down. In the 30-yard level from the Engine Shaft going west, the lode was at first almost barren in a dull chert, but after joining another equally poor it acquired a width of six yards, and contained a mass of galena six feet thick, West of this junction the vein spread into three or four strings, the northern one showing chert in the hanging, shale in the hading side. In the 48-yard level the vein was several yards broad, with chert in the hanging, and “gravel” in the hading; a cross-cut to the Engine Shaft ran for 30 yards in sand. Round ore (gravel ore) occurred in the gravel at the contact of the rock. The mine yielded galena, calamine, and a little “ white lead,” but no blende.. The galena contained more silver in the western than in the eastern part of the mine. BuckLanD also refers to this mine (as the Gronant Mine), and gives the drift-section quoted on p. 30.* The “gravel” referred to by M. MoIssENET appears to have been a glacial gravel, such as that described at Talargoch. (See also p. 47.) The sand is probably a disintegrated silicious vein- stuff, similar to that which fills the China Rake (p. 47). Parts of it are of a pure white, and so fine as to be impalpable; it contains lumps which generally crumble down when rubbed in the hand, but sometimes encloses cores of light blue chert, the. form in which probably the material was originally deposited in the vein. In other parts the vein-stuff consists of a chert _-breccia in a cement of white caic-spar with blende. Specimens of the various vein-products, of black and light coloured banded. chert, of light yellow and brown cherty sandstones with an ocva- sional fragment of encrinital chert, and of black silicious shales, may all be seen in abundance in the pit-débris. * Reliquia Diluviane, p. 178. 50 ECONOMIC GEOLOGY. Up to the close of 1861 more lead than zinc ore had: been raised at Talacre; but subsequently,-in the years 1867, 1870-71, and again in 1880-81, the periods daring which the mine was in operation, the zinc ores were in preponderance, the tendency of the blende to replace the galena in the deeper parts being even more marked here than at Talargoch. ‘he amount of lead ore raised since 1849 reaches a total of 3,575 tons 11 cwt. with a yield of cilver varying from 82 to 9} ounces per ton of lead. ‘The total yield of ziuc ores has been’ 5,556 tons 15 cwt:, the returns in 1883 and 1884 being 645 and 720 tons. No lead has been raised since 1882,.* Other Mines. Among the smaller mines may be mentioned the Golden Grove, which was being opened at the time of my survey. It is situated in a valley running past the house of this name towards Llanasa. Iwas informedt that a broad vein of spar ranging down the valley and hading to the north had: been struck, with a direction apparently of about E, 10°-15° N. The limestone exposed in the sides of the valley is dark, and thin-bedded with chert-bands, and is probably on the same horizon as that of Carreg-y-fran. Near the Volenant Telegraph Station a joint. ranging nearly east aud west through the chert has been formerly worked. It is stated that this joint is a continuation of the Talacre Vein, but there is no evidence to confirm this view. A number of small shafts were sunk, and an adit-level was driven in the underlying Black Limestone from the edge of the marsh near Terfyn toa dingle on the west side of the Gwaenysgor road. ’ Further to the west, along the same line, a shaft known as the Nant-y-Mwyn Mine was sunk to a considerable depth in the Black Limestone, but no lode was discovered. The draining of the spring by which the tufa (p. 40) was deposited was attributed to these works. A powerful stream of water is carried off at the present time by the adit-level, which was driven under Nant Mill from near the site of Prestatyn Castle. A shaft was commenced in the Drift on the north side of the road from Prestatyn to Gwaenysgor, but abandoned before reach- ing the rock. On Carreg-y-fran, a joint, running about E. 20° S., has been opened, and still shows traces of galena on_ the walls. With the intention of catching the intersection of this joint with veins supposed to range in this direction from Talargoch, a shaft was commenced in the year 1877 near the foot of the hill, but after traversing 204 feet of drift (p. 29) was abandoned without reaching the rock. From what has been previously said of the elfect of the great Prestatyn fault, it may be gathered that it is not likely that a metalliferous rock would be met with in the low ground. . = * Mineral Statistics of the United Kingdom, by Rosert Hunv. { By the agent, Mr. Ansatom Francis. , MINING. 51 Further south (west of Gwaenysgor) levels have been driven into the hill-side along joints ranging about east and east-north- east, but without resulting in any discovery. The workings of the Dyserth Mine were carried to a depth of 40 yards in a vein, which appears to have ranged N. 23° E. In the Mineral Statistics of 1869 a return of 16 tons of galena was made for this mine, and: the ore is stated to have yielded 12 ounces of silver per ton of lead,—a high proportion for this district. A deposit of iron-pyrites in a stalactitic form was met with in the western workings, probably attributable to the Coal Measure shale thrown down on the west side of the great fanlt described on p. 21. Two veins, on one of which small trials have been made, may be. traced over Cerrig Heilyn in a north-easterly direction; the southernmost is filled with a deposit of chert. The Ash-tree Shaft on the south side of the waterfall was opened on a vein running a little east of north. As previously described (p. 23) the west workings encountered the Coal Measure shale. The old lead-workings near Abergele are thus described by Mr, TIDDEMAN. Tyddyn Morgan—A road running up to this house passes eeveral shafts which have apparently been made in search of metal. Hematite and a little galena are visible in the waste-heaps. The run of the lode is E. 30° N. _ Lfos-y-Bleiddiaid—The northern end of the Castell Cawr hill has a great gash across it from top to bottom, which is named as above on the 6-inch Ordnance Map. It is evidently an old lead, mine which has at some time been very extensively worked. The vein runs about E. 18° N., and has a considerable hade to the north. It has been approached by a level, to be seen in the fields to the north-east, and at the other side of the hill must have been worked under the field ; fora large hole was formed in the middle of a crop of wheat, whilst I was in the district, by the falling in of the superficial’ deposits. Both of these veins are probably connected with the Siambr-Wen fault (p. 15). Cefn-yr-ogof.—T wo lead-veins cross this hill, and have been extensively worked. The northernmost has been entered from the Dulas Valley at Ty-newydd, and crosses the hill in a direction E. 20° N. towards a recess in the other side of the hill A level has been driven to it: from below the carriage-drive, and shafts are seen at intervals allthe way. The other vein ranges for a much reater distance. It lies about 50 yards south of the former at the Dulas Valley end, and: runs at first E.°20° S. witha hade to the south. It appears to have been a cave before it was opened out by the mining operations, and contains at its entrance beds of gravel cemented by stalagmite. ‘The workings extend all the way to Gwrych Castle, a distance of one mile, and are well marked through the entire length, Through half its length it runs as stated, then for half the remainder of its course goes east, and for the rest comes out a little to the north-west of Gwrych Castle with a north-easterly range. An adit-level is to be seen 52: ECONOMIC GEOLOGY. here. In a little plantation amongst the fields, about half-way along the vein, are to be seen many small open shafts, only just about large enough to admit the body of an average-sized man. Three hundred yards east of Tan-yr-ogof, a mining level crosses under the road to Llandulas; it has fallen in, in the field to the north, butits entrance may be seen on the shore close to the railway. It certainly was intended to drain one or other or both of these mines, but the direction which it seems to be taking would lead it past the northerly vein to the further. I saw no evidence of any rock but limestone having been met with in it. But very little of the resulting rubbish had been left by the sea. : : The following paragraph concerning these old mines, and the supposed Roman origin. of the Ffos-y-Bleiddiaid is quoted by Mr. R. Hunt* from the Records of Denbigh and its Lordship (JoHn WILLIAMS). : « At Abergele some Roman remains have been discovered. Here, as others have observed, are some of the most perfect Roman mines in the Kingdom. The mountain is cut across by a supposed Roman fosse, called Ffos-y-Bleiddiaid, or the Wolves’ Fosse. . . . . In driving a level, towards the close of the last century, the miners discovered that the. Romans had been deep in the bowels of the earth. They had followed the vein where it was large enough to admit a man, and where it opened into a large chamber, they had cleared it quite away. Some curious hammers and other tools were found, almost decayed to dust, with the golden hilt of a Roman sword. The level which drains those works partly supplies the town with water. .°. . The mines at Cae’rgwaith, at the foot of the same hill, are com- paratively modern, and were, we believe, very productive, until the water became too great for the means of drainage then ap- plicable. . . . . Some forty years ago lead was raised in solid masses of several hundredweight each, out of a shaft about a furlong to the east of the’ last-named spot; but the speculators had not the means to compete with the constant influx of water. The old mines of Tyddyn -Morgan, in the same hill, were wonder- fully productive a century back... . . . Still farther west are the old mines of Cefngo. . . . . Some thirty or forty years back, a large sum was expended in driving a level under this mountain, without meeting with anything worth the search and outlay.” | HAMATITE. Hematite is believed to have been worked on Moel Hiraddug from a very early date, I was informed by Mr. Gace of Rhuddlan, that some of the open-cast workings are attributed to the Romans, * British Mining, p. 39, 8vo. London, 1884. MINING. 53. on the.evidence of the discovery of a Roman sword and helmet, about 30 yards east of the Nickel and.Cobalt Mine. At the Cwm Iron Mine a coin was picked up, stamped with the name Wilkin- son, Iron-master of Cwm, and probably of some antiquity. The first return of ore made to the Mining Record Office was in the year 1860. The ore occurs as nodules of dark, hard, almost pure peroxide of iron in-a red? ferruginous clay, on washing which away smaller grains containing about 1 per cent. of titanium oxide are left.* Itis found in pockets or widened-out spaces in joints ranging about north-north-west. The pockets are irregular in shape, but generally bounded by curving vertical walls like those of a swallow-hole. Downwards they are usuaily terminated at a slight depth from the surface (rarely exceeding 60 yards) by the rapid closing -in of: the walls.t They are said to be richer in their contents near the top of the hill than at the base, where they are too poor to repay working. One of the principal joints in this hill is known as the Main Joint, and has been followed for a distance of about 200 yards along the east slopes, and to a depth of 60 yards. It yielded ore containing on the average 50 per cent, of metallic iron. Other old workings occur near the top of the hill, and nearer the junction of the limestone with the Basement Beds on the south side. ot : The most extensive workings are situated at Marian near Cwm in the lowest beds of the limestone, and are known as the Cwm Iron Mine. The veins run in general about N. 15° W., and have the effect of throwing the limestone down to the east about 30 yards. The ore occurred partly in veins and partly in large chambers or pockets hollowed out in the lowest bed of limestone, where it rests-upon the red shales and cunglomerates of the Basement Beds. The underlying Wenlock Shale was entered to a depth of 20 yards in the No.1 Shaft. The ground has now fallen in in the greatest confusion in consequence of the working out of the irregular deposits of ore. The mine’is stated to have yielded a total amount of 28,924 tons 17 ewts. in the years 1860-75 inclusive, the first return being 4,100 tons in 1860, but little is now being done beyond sinking shallow trial-shafts on the numerous joints in the neighbourhood. JT was informed that about 6 tons of copper ore were raised from a joint about 150 yards east south-east of Tyddyn-y-cyll. An attempt was made to drive a day-level under this ground from the ravine north of Cwm, 150 yards south of the Marian road, but was abandoned after penetrating to a distance of about 130 yards in Wenlock Shale. Further north there have been several ‘trials along the base of the limestone and in the red Basement Beds, but without any result. * See also H. Baverman, Metallurgy of Iron. 5th Edition, 1882 ; p. 69. + In the fissures of the walls of some of these cavities, snail shells thickly coated with tufa are abundant, and occasionally stags’ horns have been found. + Mineral Statistics of the United Kingdom, by R. Hunt. 54° ECONOMIC GEOLOGY. In the years 1872-75 a poot ore (averaging about 30 per cent. of metallic iron) was worked at Henfryn. It was found in veins running a little west and a little east of north, and is associated with a manganiferous ochrey clay, and with traces of copper pyrites. The quantity of ore sold amounted to 340 tons 10 cwts.* , : The trials for hzematite, which have been made in the Basement Beds in the neighbourhood of Abergele, have already been referred to (p. 7). Hamatite witH NICKEL AND COBALT. The ores of these metals have been worked on Moel Hiraddug since the year 1870.. They were first cbserved by Mr. M. A. GaGe, of Rhuddlan, (to whom I am indebted for much information concerning them,) and were described in 1882 by Mr. C. Lz Neve Fostrr.t -They occur. in an irregular chamber or cavity in the limestone, originally opened out, as may be inferred from its rounded walls, by the solvent action of carbonated water along the line of ajoint. While this cavity differs from the other metal- liferous pockets on this mountain in opening out downwards after once showing a tendency to close, the joint also is distinguished by its direction, which is about N. 33° E. The deposit has been irregularly explored to a depth of about 240 feet. ; The sides of the chamber are coated with iron oxide, in which are found occasional lumps of a hydrous sesquioxide of iron with a core of iron pyrites. Nickel and cobalt are present in small quantities in the core of pyrites, but not in the. sesquioxide crust. Very rarely solid lumps of nickel and cobalt ore have beea found, yiving hopes of the discovery of a richer deposit, which, however, have not been fulfilled. The interior of the vein or cavity is filled by a red ferruginous clay with traces of nickel and cobalt, and containing hard lumps of iron oxide associated with nickel, cobalt, and manganese, the per-centage of the two- first varying inversely as that of the last. The lumps are black and reniform, and usually are little more than pure iron oxide; smaller grains also are scattered through the mass of the clay, and are stated by Mr. Gace to be titaniferous. Analyses by Mr. Gage of three of the lumps of cobalt and nickel ore that have been found are given by Mr. Foster as follows :— Gey ey 3 . No. 1. No. 2. No. 3. Cobalt sesquioxide, . Co, O; - . 37°40 20°63 26°20 Nickel sesquioxide, Ni,Q,;- 8°58 6°85 10°35 Manganesé binoxide, Mn O,- 238°12- 39°50 ° 95°58 Iron sesquioxide, » Fe O;°+ 18°85 15°10 21°10 Copper oxide ~ - + traces traces 0°25 Silica - cs - - 0°45 2°00 0°60 Alumina - - - - 0°10 0°50: 0°18 Waiter - - - - 16°00 15°00 15°00 99°50 99°58 99°26 wee —<— * Mineral Statistics of the United Kingdom, by R. Hunt, } Trans. Roy. Geol. Soc. Cornwall, vol, x. part iv. p. 107. MINING. 55 And assays of five parcels of the ore sent to the smelters in Swansea are quoted as follows :— No.1. No.2. No.3. No.4. No.5. Per cent. Per cent. Per cent. Per cent. Per cent. Metallic cobalt - 1:0 a ile e : ’ Metallic nickel- 0°4 11 1:0 07 0°8 Total nickel and cobalt 14 2°2 22 2°3 2°6 An average assay is stated in the Mineral Statistics to give 2:05 per cent. cobalt, and 0°75 percent. nickel ; the highest per-centage amounting to 4°3 for the two together, in the year 1870, when the ore fetched 10/. 15s. per ton as compared with 4/. 18s. per ton in 1881. The total amount raised up to the close of 1884 was 1,158 tons 43 cwt., the last return being 66 tons 8 cwt. for the year 1884, yieldivg on assay 11 per cent. cobalt, and 07 per cent. nickel. ; - It’is considered by Mr. Gace that the vein products described above have been derived from the decomposition of cobaltiferous iron pyrites. The finding of lumps with an undecomposed core of such pyrites, and the occurrence of brown iron oxide pseudo- morphous after iron pyrites, seems to confirm this view. ‘A similar joint, ranging about N. 30° E., has been observed about 200 yards further south, and has been tried to a slight depth with the result of diseovering traces of nickel and cobalt ores. In another joint, however, where iron ores had been Se manganese occurred abundantly without traces of these metals. ' Traces of cobalt have been noticed in the manganese oxide of the Nant uchaf Mine near Abergele, but not in marketable quantity. The Moel Hiraddug Mine is the only source of this ore now being worked in the British Isles. HaMaTITE Wit CoprER. Allusion has already been made to the finding of a small quantity of copper pyrites near Tyddyn-y-cyll, and of traces at Henfryn. A more extensive deposit has been worked in a powerful vein at Graig-fawr, near Talargoch. The vein is a part of the great Prestatyn favlt which ranges in % south-south- westerly direction, and hades to the west-north-west. A shaft, now fallen in, was sunk upon it to a depth of 40 yards, and a brown decomposed iron ore containing green lumps of carbonate and oxde of copper was extracted. The lumps, fragments of which are still to be seen in the débris, are said to have contained about 16 per cent. of metallic copper, the ore in bulk averaging about six per cent. It has probably resulted from the decompo- sition of copper pyrites. Both to the north and south of the shalt there are old open-cast workings in the same vein, which are attributed to the “old men.” Pebbles of copper ore are stated 56 ECONOMIC GEOLOGY. by Dr. BuckLANn to have occurred also with the gravel lead- ore at Talargoch.* Prronusire (Dioxipe oR Buack OxIDE oF MANGANESE). The black oxide of manganese occurs as an amorphous powder in hollows along a very ill-defined joint in the Pentre chert-quarry near Gronant, but not in sufficient bulk to have led to any trials being made upon it. Its occurrence in small quantities in connection with the hematite deposits on Moel Hiraddug has already been referred to.. This ore, associated with hematite, has been lately worked at Nant uchaf,t about two miles south- west of Abergele, where it occurred in a thick mass in the Carboniferous Basement Beds. ‘The mine is now abandoned. On tHE PROBABILITY OF THE OCCURRENCE OF COAL UNDER tHE BuNTER SANDSTONE, | The Carboniferous rocks of the Vale of Clwyd, as has been shown in the previous pages, are in the form of a trough, faulted in among the Silurian rocks. On the east of the trough runs the great Vale of Clwyd fault, throwing down the newer Carboni- ferous rocks to the west; on the west side of the trough there are a number of faults, all throwing the beds down to the east. Tt will be clear then that the newest Carboniferous rocks will be found in the ground that separates these two systems of faults ; and the question arises, whether it is probable that the productive Middle Coal Measures of the Flintshire Coal-field occur in this area. The whole. of the ground being overspread by Drift and Bunter Sandstone, and the only trials (the Foryd and Prestatyn Bore-holes, p. 25) having been made without scientific assistance, it is possible only to infer the nature of the underlying measures from the scanty observations that are available along the borders of the Vale. On the east side the great Vale of Clwyd fault is seen in the Talargoch Mine (p. 21) to introduce measures with a thin coal, which are probably the Lower Coal Measures of the Flintshire Coal-field, These should in natural order be succeeded by the sandstone of Gwespyr (Gannister’ Series of Lancashire), and the sandstone by the productive Middle Coal Measures of Picton and Mostyn, the united thicknesses of Lower Coal Measure shales and sandstones amounting to about 300 feet. The dip of the beds as observed in the mine is towards the north-west, at a sufficiently steep angle to bring on the succession referred to within a short distance. But it is probable that the inclination of the beds decreases rapidly further away from the great fault. Even supposing this to be the case, there would appear to be * Reliquie Diluviane, p. 178. ‘ } In Quarter-sheet 79 S.W.; in the Explanation of which it will be more fally described. MINING. 57 room for the succession between Dyserth and Rhyl, a distance of nearly 34 miles. : : On the west side near Abergele the upper boundary of the limestone is hypothetical (p. 25) ; but there is no doubt, from the general strike and dip of the limestone range, that it is succeeded towards the north-north-east by newer Carboniferous rocks, which would probably also dip in this direction.* Haviug regard to the positions of the faults, and direction of the dip on the two sides of the Vale, it appears that the deepest part of the trough should lie between the mouth of the Clwyd and Prestatyn, between the two bore-holes at the Foryd and near Prestatyn (indicated on the map); and that in this deepest part there is a reasonable probability that Middle Coal Measures may occur. The depth of the overlying superficial deposits in this area would probably average about 80-100 feet, and of the Bunter Sandstone about 500 feet, along the sea-coast. As to the southern limit of this supposed patch of Middle Coal Measures, there is no evidence. It is not probable that they extend beyond, if so far as, the southern margin of this Map. Quarriss, Brick-pits, &c. The principal limestone quarries are at Llandulas, and Dyserth (p- 10). The white limestone used in building Bodlewyddan church is found in the hills south of Abergele. The chert-quarry at Gronant, and the white sand of Talargoch, have already been referred to (pp. 19 and 47). Bricks are made from the red Boulder Clay.in the Vale of Clwyd and Colwyn Bay, and near Rhy] also of the marsh clay (tidal slutch) on the south side of the town. * The dip of the puxple sandstones in the nearest exposure, near St. Asaph, was found by Mr. Trpprman to be to the south. But, bearing in mind the general structure of the Vale, one would be inclined to regard this as merely local, especially as it occurs near a line of fault. e 58 APPENDIX I. OBSERVATIONS ON. UNDERGROUND TEMPERATURE IN THE TataraocH LErap MINE. These observations were made in company with. Mr. A. O. WaLKER, and with the assistance of Mr. Lean, the captain of the mine. The thermometers used were'slow-acting instruments, by NEGRETTI AND ZAamBRA, as constructed for the Committee appointed by the British Association for the investigation of underground temperatures.* The errors of the thermometers had been determined at Kew, and are corrected in the readings given below. The observations were made as follows :—in a newly opened part of the mine a hole was bored in the side of the level to a depth of 24 inches, and plugged up with clay and dry rag. After the lapse of some hours the thermometer was inserted, and the hole again plugged as before. After four or six days interval the thermometer was taken out, read, and inserted as before. A second reading was made a few days later.. If the two readings were found to agree, the observation was considered reliable. The positions of the observations are indicated on the Map (see Plate) by corresponding letters. Talargoch Vein. Feet from surface. Temperature. Rate of Increase. A. 465 58 35° 1° in 77 feet B. 1041 60°80° } oe South Joint. . 1 e oe ao fis in 974 feet. In solid rock, near Walker’s Shaft (1000 yards from the preceding). *QO yp et eee fis in 543 (calculated). The following table gives the temperatures as calculated for the same depth (680 feet) in the three localities. Talargoch Vein South Joint Solid rock (Walker’s Shaft) (calculated). (calculated). (observed). 55°46° 53°97° 588° The great differences in the rate of increase of temperature in different parts of the mine may perhaps be due to the very faulty nature of the ground. In some cases the rock overlying the point of observation was principally shale, in others limestone, in part thick-bedded and massive, in part thin-bedded and shaly. The observations near Walker's Shaft were near the Vale of Clwyd fault, in which there is abundance of iron pyrites,and the water from which is charged with sulphuretted hydrogen. It is possible that chemical action may be now proceeding and locally raising the temperature here. The temperature of the water being pumped from the 256 yard level was 63°. 2 * For whom the observations were originally made. See Rep. Brit. Assoc. for 1880, p. 26; for 1881, p. 90. 59 APPENDIX II. LIST OF WORKS ON THE GHOLOGY, &e. OF: DENBIGHSHIRE AND FLINTSHIRE. . By WIttiam WHITAKER, B.A., F.G.S., Assoc. Inst. GE, and AUBREY Srranan, M.A., F.G.S. . List oF AUTHORS ALPHABETICALLY ARRANGED.* Acton, E. H. ' 1881. Aikin, A. 1797. © Aitken, J. 1870. Anon. 1819, 1831, 1863, 1874. Ansted, Prof. D. T. 1878. Aveline, W. T. 1850-55, 1858, 1885. Bamber, H. K.. 1875. Barrat, J. 1860. Bauerman, H. 1858. Beaumont, H.de. 1825. Beckett,"H. 1864, 1873. Bingley, Rev. W. 1814. Binney, E. W. 1860, 1867. Bishop, W. 1822. Bonney, Rev. T.G. 1867, 1869. Bostock, R. 1868. Bowman, J. E. 1887, 1841. Brady, H. B. 1873. Bretherton, E. 1856. Buckland, Rev. Prof. W. 1823, 1843, 1844, ° : Burr, F. 1837. Clarke, Dr. E. D. 1817. Coal Commission. 1871. Conybeare, Rev. W. D. 1822, 1834. Croft, Rev. C. 1882. Crosskey, Rev. H. W. 1875, 1877, 1878. - Da Costa, E. M. 1758. Darbishire, R. D. 1868. Darlington, G. 1862. ; Davies, D. C. 1859, 1864, 1865, ' 1870, 1878, 1876, 1877, 1881, . 1883. Davies, W. 1813. Davidson,.T. 1861, 1868. Dawkins, Prof. W. B. 1870, 1874, . 1880. 7 De Rance, C. BE. 1882, 1883, 1885. Dickinson, J. 1871, 1874. Duckworth, H. 1861. Dufrénoy, P. A. 1825. Eskrigge, R. A. 1880. Etheridge, R. 1881, 1882. Evans, Rev. J. 1812. Everett, Prof. J. D. 1880, 1882. Eyton, Miss. 1866, 1868. Fairbairn, W. 1842. Farey, J. 1815. Flight, Dr. 1872. Foster, Dr. C. Le Neve. Fox, R. W. 1832 Frankland, Prof. H. 1874. Green, Prof. A.H. 1867. Griffith-Boscawen, A. S.J. 1883. Griffith, N. R. 1870. Haime, J. 1852. Hall, C.R. 1865. Hall, H. F. 1866, 1870. Harrison, W. J. 1882. Henwood, W. J. 1871. Hicks, Henry. 1876, 1881, 1882, 1885. Higgins, W.M. 1868. Hofer, H. 1884. Hopkins, J. 1853. Hughes, Prof.T, McK. 1874, 1877, 1879, 1882. Hull, EH. 1850, 1855, 1858, 1860, 1862, 1869, 1881. Hunt, R. 1855-82, 1868, 1884. Jukes, J.B. 1850-55, 1865. Lucy, W. 0. 1873. . Mackintosh, D. 1866, 1868, 1869, 1872, 1873, 1874, 1876, 1877, 1879, 1881, 1882. Marr, J. H. .1880, 1883. Maskelyne, Prof. N. 8. 1882, 1872, * The dates printed thus 1850 are those of the publications of the Geological Survey and Mining Record Office. A 17240, E 60 Maw, G. 1865, 1866, 1867, 1868, Rowlandson, TI. 1847.. M‘Coy, Prof. F. 1851. Ruddy,.T. 1879. Meade, R. 1877, 1882. . Mello, Rev. J. M. 1867. Salter, J. W. 1866, 1873, 1882. Milne Edwards, Prof. H. °1852. Sedgwick, Rev.- Prof. A. 1838, Moissenet, M,L. 1857. 1841, 1848, 1844, 1845, 1847, 1852, Moore, CO. 1870. 1855. Moore, T. J. 1867. Selwyn, A. R. 1850-52, 1854, Morris, Prof. J. (1862. . |. 1855. is : Morton, G. H. 1866, 1869, 1870, (Sharpe,"D. 1846. 1873, 1874, 1876, 1877, 1878, 1879, Shrubsole, G. W. 1879, 1881. 1881, 1882, 1883. , Smith, Dr. R. A. 1884. Morton, J. ©. 1874. Smythe, W. W. 1850. Mostyn, R. 1677. Stanley, Rey. EH. 1832. Murchison, Sir B. I. 1839, 1854, “ Strahan, A. [879, 1882, 1885. 1867. Stirrup, Mark. 1881. att Symonds, Rev. W. S.,. 1872. Ness, W. 1865. : Le Nixon, H. 1866. Teall, J.J. H. 1880. : Thomas, J. E. 1867, 1873. Page, Dr. D. 1875. Thomas, Rev.-D: B.. 1874. Parry, R. 1861. ; Tiddeman, R. H. 1885. “Parry, Samuel. 1876 Traill, Dr. T.S. 1821. Pennant, T. 1757, 1778, 1796,1810. Trimmer, J. 1838, 1839. Percy, Dr. J. 1875. - ; Phillips, William. 1822. Vivian, W. 1872. Price, J. 1874. : : Prichard, Dr. J.C. 1815, Walker, A.O. 1878, 1879. Prosser, W. 1865. Wallace, A: R, 1867. — Purton, W. 1866. Waller, W. 1700. Whitaker, W. 1880. Ramsay, Sir A.C. 1850-52,1854, Williams, D.H. 1850, 1858. 1866, 1863, 1871, 1872, 1876,1881. Williams, J. J. ‘1876. Reade, T. Mellard. 1885. Williams, W.M. 1865. Ricketts, Dr. C. 1867, 1872. Wright, T. 1862. Riley, H. 1862, 1872. . Wynne, Mrs. W.. 1882. Rivers Pollution Commission. 1874. Roberts, D. W. 1870. Yates, Rev. J. 1825. Roberts, G. H. 1858, 1862. ; Grotogicat Survey Pusrications. Sheets of the Map. (Scale, an inch to a mile.) 73, N.W. (Whitchurch, Malpas). By A. R. Setwyn and E. Hurt. 1855. 74, S.W. (Bala). By A.C, Ramsay, J.B. Juxus, W. T. Ave.inn, and A. RB. Setwyn. 1850. Corrections, 1855. 74, N.W. (Corwen)., By A. C. Ramsay, J. B. Juxzs, and W. T. AvEine. Corrections, 1855. ae : ; ; 74, §.H. (Lianrhaiadr), and N.E. (Llangollen, Wrexham). By A. 0. Ramsay, J. B. Juxus, W. T. Aveuins, D. Wintiams, and BE. Hut. 1850. Corrections, 1855. . “75, N.H. (Tremadoc). By A. C. Ramsay, A. R. Suuwry, W. T. AvELINE, and J.B. Jukes. 1851... Additions, 1854. . ... wh. Tks 78, 8.H. (Bangor, Beaumaris, Llanrwst), and N.B. (Conway). By A. C. Ramsay, W. T. Avetinu, A. R. Setwyn, and J. B. Juxus. 1852. °. 79, S.W. (Denbigh, St. Asaph). By W. T. Avetins. Tle Lodes by W. W. Suyra. 1850. | sss : cones : 79, 8.H. nearly all (Flint, Mold). By W. W. Suyrs,.D. H. Wituams, W. T. Averys, and E. Hutt. 1850. (Re-survey by C. EH. Dz Rance and A. Srraway, engraving). 61 79, N.W. (Abergele). By A. C, Ramsay, W. T. Avzetine, and W. W.- Smyru. 1850.. Re-survey by W. T. Averine, R. H. Trppemay, and A. Srrawan. 1885. ie 79, N.E. (N. of Holywell). By W. W. Smyta and E. Hutt. 1850. Re- survey by C. BE. De Rancz and A. Srrawan. 1885. “ee (Chester). By E. Hurt. 1855. Re-survey by A. Srranan, we den 8 ‘ a i i Sheets of ‘‘ Horizontal Sections.”? (Scale, 6 inches to a mile.) “81, 82, and 83. Section from the Suspension Bridge, Menai Straits [to the River Camlad, 6 miles 8.E. of Welshpool]. By A.C. Ramsay, A. R. Setwrn, W. T. Avetine, ana J. B..Juxes. 1854. 35. From Cwm Cywen, 44 miles N.E. of Bala, over Cader Berwyn, the Breidden Hills . . ,, By J.B. Jukes and W. T. Avetine. 1853... 38. (Section 2.) From 3} miles W.N.W. of Meifod, Montgomery, to the head of the Vale of Clwyd. By J.B. Juxzs and W. T. Avezinz. “1855. ~ 39. Section from Arenig Fawr to.the Coal Measures near Wrexham. By J.B. Juxes and W. T. Avetins, 1855. vis a 43, Across the Wenlock Shale W. of Ruthin, the . .~. Vale of Clwyd; the Flintshire Coalfield between Mold and the Dee. By W. T. Avztinz, E. How, and H. Baverman. 1858. New edition in preparation. 44. No. 1. Across the Denbighshire Coalfield, through Bwlch Gwyn and Brymbo; the Permian Rocks North of Wrexham ...-- . By D.H. Wiiuramsand E. Hutt. No.2. Through Tan-y-Castell, across the Denbigh- shire Coalfield . . . By D. H. Witttams. 1858. aaa Sheets of “ Vertical Sections.” (Scale, 40 feet to 1 inch.) 24. Section of the Coal Measures between Sweeney Mountain, near Oswestry, and Brymbo, N.W. of Wrexham. By D. H. Wiutiams. No date, : ; 8 . ‘ ) 4 Memoirs. (8v0, London.) Vol,, iii, (1866). ‘The Geology of North Wales.” By Prof. A. C Ramsay. ‘With an Appendix on the Fossils. By J. W. Satter. Edition 2 in 1881. au Mining Record Office. - Fa ' Catalogue of the Contents of the Mining Record Office. By Rozerr Hunt. 8vo. London, 1858. = Mineral Statistics of the United.Kingdom for the years 1853-81. By R. Hunt. 8vo. London. 1855-82. ¢ vrpe Booxs, Papers, &c., CHRONOLOGICALLY ARRANGED. : an 1570. Cambrian Register. ou 1677. Mostyn, R.—A Relation of some strange phenomena, accompanied with mischievous effects in a Cole-work in Flintshire. Phil. Trans., vol. xii. (No. 136), p. 895. , E 2 62 e 1700. Water, W.—State of the Lead, Silver, and other Mines in Wales (? date). 8vo. ; 1757. Pexwant, T,—An Account of some Fungite and other curious Coralloid fossil bodies. Phil. Trans., vol. xlix. (part 2), p. 513. 1758. _ Da Costa, E. M.—An Account of the Impressions of Plants on the Slates of Coal. Phil. Trané., vol. 1, p. 228. - 1778-1783. : : PEnwawn, T.—A Tour in Wales. (Mineral Tract; &c., pp. 415-424). 4to. London. ~ 1796. . Pennant, T.—The History of the Parishes of Whiteford and Holywell. 4to. London. 1797. Arkin, A.—Journal of a Tour through North Wales and part of Shrop- shire, with observations on Mineralogy and other branches of Natural History. 8vo. London. (See also Jowrn, Nat. Phil., Chem .and Art., vol.i., pp. 220, 367. Ato.) 1810. Pennant, Tuos.—A Tour in Wales in 1773. 8vo. London. eS : 1812. ° Ds 442, 1846, Suarre, D.—Contributions to the Geology of North Wal Se ; Tourn. Geol. Soc., vol. ii., p. 283. a a Oe 1847, Rowxanpsoy, T.—Agriculture of North Wales (with an account of Geology and Soils), Jowrn. Roy. Agric. Soc., vol. wie p.-553. the Sepewick, Rev. Pror. A.—On the Classification of the Fossiliferous Slates of North Wales, Cumberland, Westmorland, and Lancashire. eee Journ. Geol. Soc., vol. iii., p. 183. 1851. . M‘Coy, Pror. F.—Descriptions of some new Mountain Li st Ann. Mag. Nat, Hist., ser. 2, vol. vii., pp. 167 and 178. eee 65 1852. Mine Epwarps, Pror. H., and J. Harme. A Monograph of the British Fossil Corals. Third Part. Corals from the Mountain Limestone. Pa- leontograph Soc. 4to. London. Sepewick, Rev. Pror. A.—On the Classification and,Nomenclature of the Lower Palzozoic Rocks of England and Wales. Quart. Journ. Geol. Soe., vol. viii., p. 136. 1853. Horxins, J.—Presidential Address to the Geological Society. Quart. Journ. Geol. Soc., vol. ix., p. lxi. : 1854. Mourcutson, Siz R. I.—Siluria. 8v0. London. (Hd. 2, 1858; Ed. 3, 1859; Hd. 4, 1867). ‘ 1855. Sepewicx, Rev. Pror. A.A Synopsis of the British Palwozoic Rocks. With a Systematic Description of the British Paleozoic Fossils in the Geological Museum of the University of Cambridge, by Pror. F. M‘Coy. 4to. London and Cambridge. 1856. BrerHERTon, E.—A Geological Ramble (Ruthin, é&c., Denbighshire). Proc. Lit. and Phil. Soc. Liverpool, No. x., p. 148. , 1857. Morssenet, M, L.—Mémoire sur le Gisement du Minerai de plomb, dans le cacare Carbonifére du Flintshire. Annales des Mines, ser. 5. tom, xi., p. 351. 1858. Rosents, G. E.—On the Geology of Llandudno. Geologist, vol. i., p. 448. " 1859. Davins, D. C.—On the Hastern Boundary of the North Wales Coalfield near Oswestry. Proc. Geol. Assoc., vol. i., p. 14. 1860. Barat, J.—Analysis of the Water of Holywell, North Wales. Quart. Journ, Cheri. So¢., vol. xii., p. 52. it Binney, E. W.—Observations on the Fossil Shells of the Lower Coal Measures. Trans. Manchester Geol. Soc., vol. ii. (part 7), p. 72. Hout, E.—The Coalfields of Great Britain, &c. 8vo. London. (Hd. 2, 1861; Hd. 3, 1873; Hd. 4, 1881.) ~ 1861. Davipson, T.—A Monograph of the British Fossil Brachiopoda,: Part V. The Carboniferous Brachiopoda, No. 4. (Wales, Plates 31, 37, 40, 45.) Paleontograph Soc. 4to. London. ae : Ducxwortx, H.—Report of Excursion to Holywell (Liverpool Geoi. Soc.) Geologist, vol. iv., p. 505, and Proc. Liverpool Geol. Soc., vol. i. _ Parry, R.—Llandudno, its History, Natural History, and Antiquities. 8vo. Llandudno. 1862. Darurneton, G.—Mineral and Geological Sketch of the Minera Mining Field, Denbighshire, North Wales. Mining and Smelting Mag., vol. ii., pp: 207, 269. . oe : 66 Huu, E.—The Coalfields of North Wales. bid., vol. i., p. 295. Morris, Pror. J., and G. HE. Roserts.—On the Carboniferous Limestone of Oreton and Farlow, Clee Hills, Shropshire ; with a description of a new species of Pterichthys, by Sir P. pp M. G. Eeenton. Quart. Journ. Geol. Soc., vol. xviii., p. 94. 4 : 1 : . Ritey, E.—On the Manufacture of Iron (Analyses of Ores and Coals). Trans. Soc. Hng. for 1861, p. 59. ° Wricut, T.—Roman Mining Operations on ‘the borders -of Wales. Intellectual Observer, vol. i., p. 295, 7 1863. Anon.—Bone Cave at Cefn, Flintshire. Geologist, vol. vi., p. 114. Davison, T.—A Monograph of the British Fossil Brachiopoda. Part V. The Carboniferous Brachiopoda. No.5. (Wales, Plates 51,55.) Palconto- graph Soc. 4to.. London. Ramsay, [Sm] A. C.—The Physical Geology and Geography of Great Britain. 8vo. London. (Other editions in 1864, 1872, 1874, 1878.) a 1864. Brcxerr, H.—On the Recent Discovery of Cannel Coal in North Wales. Trans. Dudley and Midland Geol. and Set. Soc. (vol. i.?), No 3., p. 87. Davies, D. C.—Tourist’s Guide to Llangollen and its Vicinity, &c. Edit. 3. (With notes on the Geology.) 12mo. Llangollen. : 1865. Davies, D. C.—The Geology of Glyn Ceiriog. Geol. Mag., vol. ii., p. 32. -—Denudation, Unconformability, and the Vale of Clwyd. Geol. Mag., vol. ii., p. 476. .—On the Discovery of Fossils in the Millstone Grit near Oswestry. Rep. Oswestry Field Club, 1857-64, p. 41. ——.—The Mountain Limestone of North Wales. Oswestry and Welshpool Nat. Field Club, 1865, p. 50. : Haut, C. R.—Some Conjectural Hints towards determining the ancient Coast-line of North Wules between the River Dee and the Island of Anglesea. Geol. Mag., vol. ii., p.78; and Proc. Liverpool Geol. Soc., Sess. 6, Jukes, J. B.—Former extension of the Coal Measures. Geol. Mag., vol. ii., p. 185. . ‘ ! Maw, G.—On some deposits of Chert, White Sand, and White Clay in gue neighbourhood of Llandudno, North Wales. (Geol. Mag., vol. ii., p. 200. ———.—Permian Strata in the Vale of Clwyd. Geol. Mag., vol, ii., pp- 380, 523. : —Letter on Quartz at Talargoch Mine, Flinishire. Ibid., p. 428. Ness, W.--On the Coal Measures in the Mold Valley, and their Products (Brit. Assoc.). Geol. and Nat. Hist. Repertory, vol. i., p. 186. Prosser, W.—Fossiliferous Character of the Millstone Grit at Sweeney, near Oswestry, Shropshire. Geol. Mag., vol. ii., p. 107. Witirams, W. M.--On the Ancient Glaciers on the North and East of Llangollen, and more particularly of the neighbourhood of Hope Mountain. Rep. Brit. Assoc. for 1865. Trans. of Sections, p. 77 (1866), and Geol. and Nat. Hist. Repertory, vol. i., p. 169. ; “1866. Exron, Miss.—On an ancient Coast-line in North Wales. Geol. Mag., vol. iii., p. 289. ee : Haut, H. F.—Notice of Submerged Forests at Rhos, near Colwyn. Proc. Liverpool Geol. Soc., Sess. 7, p. 31. Macxintosu, D.—The Sea against Rivers; or the Origin of Valleys. Geol. Mag., vol. iii., pp. 155, 235. . gene nsio . Ibid., p. 280. -—Results of Observations .on the Cliffs, Gorges, and Ht Wales. Ibid., p. 387, Rs . eee 67 Maw, G.—On some Fossiliferous Slates occurring between the Bunter Sandstone and Mountain Limestone of the Vale of Clwyd. Rep. Brit. Assoc. for 1865, Sections, p. 67; (Geol. Mag., vol. ii., pp. 380, 528.) .—On an extensive Distribution of White Sands and Clays in North Wales antecedent to the Boulder Clay Drift. Rep. Brit. Assoc. for 1865, Sections, p. 68, (and Geol. Mag., vol. ii-, p. 200). : : .—On the occurrence of extensive Deposits of Tufa in Flintshire. Geol. Mag., vol. iii., p. 253. Morton, G. H.—Introductory Remarks on the Geology of the Country between the Vale of Clwyd and the River Dee (Liverpool Geol. Soc.) Geol. Mag., vol. iii., p. 86. (abstract.) . —-.—On the Geology of the Country bordering the Mersey and Dee. Liwerpool Naturalists’ Journal, No. 1., p. 15. Nixon, E.—The Coalfields of Denbighshire and Flintshire. Proc. Liverpool. Geol. Soc., Sess. 7, p. 46; and Geol. Mag., vol. iii., p. 182. ’ Purron, W.—Marks of Sea action on the Cliffs and Gorges of Wales. Geol. Mag., vol. iii., p. 522, 1867. Brixyey, E.. W.--On the Upper Coal Measures of England and Wales. Trans. Manchester Geol. Soc., vol. vi., p. 38 Bonney, Rev. 'T. G.—On Traces of Glacial Action near Llandudno. Geol. Mag., vol. iv., p. 289. .—Kitchen Middens on the Great Orme’s Head. Jbid., pp. 343, 526. _ Green, A. H.—On the Lower Carboniferous Rocks of North Wales. Geol. Mag., vol. iv., p. 11. Maw, G.—On the Distribution beyond the Tertiary Districts of White Clays and Sands subjacent to the Boulder Clay Drifts. Geol. Mag., vol. iv., pp. 241, 299. ‘ .—Shells on the Great Orme’s Head (Letter on). Ibid., p. 377. Me to, Rev. J. M.—Note on the Contents of the Pockets in the Car- boniferous Limestone at Llandudno. Ibid., p. 527. —— .—Kitchen Middens at Llandudno. Jbid., p. 533. Moors, 1T'. J.--Mammalian Remains from Cefn Cave. Part I. Proc. Liwerpool Geol. Soc., Sess. 8, p. 50. Morcuison, Sir R. I.-—Siluria. 4th edition. 8vo. London. Ricketts, Dr. C.—On the outlier of Carboniferous Limestone near Corwen, North Wales. Ibid., p. 3. . Tuomas, J. H.—Prize Essay upon the Encroachment of the Sea between the River Mersey and the Bristol Channel. 8vo. London. Watuacr, A. R.—Ice Marks in North Wales (with a sketch of Glacial Theories and Controversies). Quart. Journ. af Science, vol. iv., p. 33. : 1868. Bostocx, R.—On the probable Source of Holywell Spring. Pyoc. Liver- pool Geol. Soc., Sess. 9, p. 62. : Darsisuine, R: D.—Notes on Superficial Deposits at Great Orme’s Head, and as to the Period of its Elevation. Mem. Lit. and Phil. Soc. Manchester, vol. iv., p. 1. ‘ . Eyton, Miss.—-The Drift Beds of Llandrillo Bay, Denbighshire. Geol. Mazg., vol. v., p. 349. ae _ Hiceeins, W. M.—The Geological Distribution of the Iron Ores of Great Britain. (Reprinted from the Colliery Guardian.) 4to. London. : ‘Hunr, R.—The Iron Ores of Great Britain. Quart. Journ. of Set., vol. v., p. 31. . 7 os . Macxintosu, D.—On the Origin of Smoothed, Rounded, and Hollowed Surfaces of Limestone and Granite (Minera). Quart. Journ. Geol. Soc., vol. xxiv., p. 277 (abstract). - -Maw, G.—On the disposition of Iron in Variegated Strata. Quart. Journ. Geol. Soc., vol. xxiv., p. 351. (Wales, pp. 360, 379, 380-82.) 68 1869. beg ay : Bonney, Rev. T. G.—On the supposed Occurrence of Pholas Burrows i in the Upper Parts of the Great and Little Orme’s Heads. Geol. Mag., vol. vi., p. 483. Letter on the above, vol. vii., p. 93, 1870; and by R. D. Dar- BISHIRE, p. 92; and Proc. Camb. Phil. Soc., part x1., pp. 150-152. Hoxt. E.-—On the Evidences of'a ‘Ridge. ‘of Lower Carboniferous Rocks crossing the Plain of Cheshire beneath the Trias, and forming the boundary between the Permian Beds of the Lancashire Type on the North, and those of ibe Salopian Type on the South. Quart. Journ. Geol. Soc., Vol. xxv., Pp. Macxintosu, D.—The Scenery of England and Wales; its character and origin. 8vo. London. Morton, G. H.—Palontological- Observations on the Carboniferous Limestone in Flintshire. Proc. Liverpool Geol. ‘Soc. -, Sess. 10, p. 75. 1870. Arrxen, J.—On Productus Liangollensis from the Belwyseg, Rocks, Llangollen. Trans. Manchester Geol. Soc., vol. ix. (No. 1.), p. 9 -—The Grit Rocks of the Eastern Border of North Wales. Geol. Mag., vol. vii. - P 263. ; Davies, D. C.—On the Millstone Grit of the North Wales Border. Geol. Mag., vol. vii., Pp. 68-122. i Dawkins, W. B.—The Denbighshire Caves. Trans. Meebeaten Geol. Soe., vol. ix. (No. 1.), p. 31. Gaivrirn, N. R.—On the Flintshire Cannel Seam. Trans. N. Inst. Mining Eng., vol. xix., p. 75. Hau, H. F.—On the Glacial and Post-Glacial Deposits in the neighbour- hood of Llandudno. Geol. Mazg., vol. vii., p. 509; and Rep. Brit. Assoc. for 1870, Sections, p. 72. Moorx, C— eport on Mineral Veins in Carboniferous ifienetbone and their Organic Contents, with notes on the Foraminifera by H. B. Brapy. Be. Brit. Assoc. for 1869, p. 360. orton, G. H.—The Mountain Limestone of Flintshire and part of Denbighshire. Rep. Brit. Assoc. for 1870, Sections, p. 82. Rozerts, D. W.—Notice of the occurrence of ‘‘ Actinoctinus pulcher ” in the Upper Silurian Flag of Denbighshire, North Wales, being: a new locality for this Encrinite. Trans. Edin. Geol. Soc., vole i., p. 829. ° 1871. Henwoop, W. J.—Observations on Metalliferous, Deposits (N. Wales, pp. 635-642). Trans. Roy. Geol. Soc..Cornwail, vol. viii., part 1. Report of the Commissioners appointed to inquire into the various matters relating to Coal in the United Kingdom. J. Dickinson. Lanca- shire, Cheshire, North Wales, &c., vol. i., pp. 16-19, Pror. A. C. Ramsay. On the probability of finding’ Coal under the Permian, New Red Sand- stone, and other Superincumbent es pp. 119-145. See alse ; Minutes and Hvidence, vol. i. ‘Pol. Lond a te 1872. rea D.—The Age of Floating Ice in North Wales. Geol. May., vol. ix., p MAsKELYNE, Pror. N. §., and Dr. Furient. —Mineralogical Notices. 12 Analyses of some Pisolitic Iron Ores from North Wales. Journ. Chem. Soc., ser. 2., vol. 7 p. 1055. Ramsay, Pror. | C.—On the River Cosmas: of England and Wales. Quart. Journ. Gea Soc, vol. xxviii., p. 148. ‘Ricketts,’ Dr. C.—Valleys, Deltas, Bays, sl Estuaries (President’s Address). Proc. Liverpool Geol. Soc., Sess. 1871-72. Ritzy. E.—The Manufacture of Iron and Steel (Analysis of Welsh Iron- stone, p. 534). Quart. Journ. Chem. Soc., ser. 2, vol. x., p. 533. Symonps, Rev. W. 8.—Records of the Rocks ; or Notes on the Geology, ‘Natural History and Antiquities of North and ‘South Wolke, Devon and Cornwall. Post 8vo. London. ‘ 69 Vivian, W.—Rocks.—Do they grow? Trans. Cardiff Nat. Soc., vol. iii., [pt. 1.], p..78, pl. 8. 1873. BEcKETT, H.—The sGeiiey of the Minera District. Trans. Severn Valley Nat. Field Club, 1865-70, p.'85. Brapy, H. B. “On Archewodiscus Karreri, a new. type of Carboniferous Foraminifera. Ann. and Mag. Nat. Hist., ser. 4, vol. xii., p. 286. Davizs, D. C.—On the Oscclvgoine of several Geological Formations on the North Wales Border. Proc. Geol. Assoc., vol. ii., No. 8, p. 299. On Coal Seams in the Permian at Ifton, Shropshire, Proc. Geol: -Assoc., vol. iii., p. 138. Lucy, W. ".—Notes on the Extension of the Boulder Clay on the Great and Little Orme’s Head, and the cementing together by Lime of some large Boulders in the Clay near the Little Orme. Geol. Mag., vol. x., p. 341. Macxintosu, D.—Observations on the more remarkable Boulders of the North- west of ‘England and the Welsh Borders. Quart. Journ. Geol. Soc., vol. xxix., p. 351. Morrow, G. H.—The Strata below the Trias in the country around Liverpool, and the probability of Coal occurring at a moderate depth. Proce. Lit. and Phil. Soe. of Liverpool, vol. xxvii., p. 157. Satter, J. W.—A Catalogue of Cambrian and Silurian Fossils ; ; witha Preface by Pro#. Supewick. 40. ’ Cambridge. Tomas, J. H.—Prize Essay upon the Mineral Resources of the Counties of Flint and Denbigh, with’ suggestions for their development: pp. iv., 41. 8vo. ea, : = - . 1874, Mae _Physical Features ” and ‘‘ Geology” in Murray’s Handbook for North Wales. Hd. 4, pp. v.-xvi. 8vo. London... Dawkins, W. B. —Cave Hunting. Researches on the Evidence of Caves respecting the Early Inhabitants of Europe. (Coloured plate and woodcuts.) Pp. xix., 455. 8vo. London DICKINSON, J.—On the Salifarona Strata. Trans. Geol. Soc. Manchester, vol. xiii., partir, p. 23. (Refers to Hafod-y-bwlch Colliery, Denbighshire.) Houeues, Pror. T. McK., and Rev. D. R. Taomas.—On the Occurrence of Felsite Implements of the Le Moustier type in Pontnewydd Cave, near Cefn, St. Asaph. Jowrn. Anthrop. Inst., vol. iii., No. 3, pp. 387-392. With plate (section). Macxintosu, D.—On a New Section of Pre-Glacial White Clay and Sand near Mold [Flintshire]. Geol. Mag., dec. ii., vol. i., pp. 67, 68. —, -—-.— Scotch Granite on Welsh Hills. Ibid., p. 95. ——, -—.— On the Traces of a Great Ice-sheet in the Southern Part of the Lake District, and in North Wales. Quar. Journ. Geol. Soc., vol. xxx., pp. 174-179. (Map.) —-, -—.— Additional Remarks on Boulders, with a particular reference to a Group of very large and far-travelled Erratics in Lianarmon Parish, Denbighshire. Ibid., pp. 711-721. Morton, G. H.—The Carboniferous Limestone and Millstone Geil of North Wales. Part I. “Proc. Liverpool Geol. Soc., Sess. 15, pp. 16-19. - (A list of 30 works relating to the subject, published between 1778 and 1873. ) ‘Price, J.—Llandudno, and how to Enjoy it. Being a handy Guide to the Town and Neighbourhood. 8vo. London, 152 pp. and Map. Rivers Pollution Commission, 6th Report. Pror. -E. Epa cis and J.C. Mortoy. Folio. London. 1875. Bamper, H. K.—[Analysis i: ate Minera Firestone.] Trans. N. Engl. Inst. Min. E'ng., vol. xxiv., pe Crosskzy, Rev. H. W.— Ae Report of the Committee appointed for the purpose of recording the position, height above the sea, lithological 70 characters, size, and origin of the more important of the Erratie Blocks of England and Wales, reporting other matters of interest connected with the same, and taking measures for their preservation. Rep. Brit. Assoc. for 1874, pp. 192-200. os a ; Paces, Dr. D.— On Minera Firestone. N. Engl. Inst. Min. Eng., vol. xxiv., . 154, : 2 ; ; e Percy, Dr. J.—Metallurgy. Enlarged edition, Analysis of Buckley Firebricks; p. 150, 8vo. London. ’ 1876. _ Davies, D. C.--On- some of the Causes which have Helped to Shape the Land on the North Wales Border. Proc. Geol. Assoc., vol. iv., No. 6, pp. 850-352. 17 woodcuts. OT tes de sear . ——, -——-.—On the Drift of the North Walesa Border. Ibid., No. 7, pp. 423-439, pl. v. (sections. ,-——-— Excursion to the North Wales Border. Ibid., No. 9, pp. 559-568, Hicxs, Heyry.—On some areas where the Cambrian and Silurian Rocks occur as Conformable Series. Rep. Brit. Assoc. for 1875, Sections, p. 69, .. Macxiytosu, D.—On the Correlation of the Deposits in Cefn and Pont- newydd. Caves with the Drifts of the North-west of England and Wales. Quart. Journ. Geol. Soc., vol. xxxii., pp. 91-94. eat 5 , —--On the Mode of Occurrence and Derivation of Beds of Drifted Coal near Corwen, North Wales. Ibid., pp. 451-453. -———, —.—On the Origin of two policion and sharpened Stones from Cefn Cave. dtep. Brit. Assoc. for 1875, Sections, pp. 75;, 76. 2 »—-— Result of Observations on the Eskers, Lake Basins, . and Post-glacial Rivercourses of Cheshire, Shropshire, Denbighshire, and Flintshire, with Remarks on the Sequence of Glacial Events in the N.W. . of England and Wales. (Read before the Chester Society of Natural Science, February 1876.) Abstract in Geol Mag., dec. ii., pp. 272-274, Morton, G. H.—Records of Glacial Strie.in Denbighshire, Flintshire, and Anglesea. Proc. Liverpool Geol. Soc., vol. iii., part 11, pp. 123-126. --, -——.—The Carboniferous Limestone and Millstone Grit of North Wales. Jbid., pp. 152-205, : --, ——-.—Notes on the Relation between the Mineral Flint and the County of Flint. Jbid., pp. 94-96. ; ; Parny, Samvet..—Human Remains beneath Boulder Clay? Geol. Mag., dec. ii., vol. iii., p. 528. , : e2. / Ramsay, Pror. A. C.—On the Physical History of the Dee, Wales. Quart. Journ. Geol. Soc., vol. xxxii., pp. 219-229. (Folding section.) Wiuams, J. J.—The Mineral Resources of Flintshire and Denbigh. shire. Trans. N. Engl. Inst. Min. Eng, vol. xxv., pp. 81-100, (Map and woodcut.) a 24 ne 1877. Crosskzy, Rev, H. W.—Fourth Report of the Committee appointed for the purpose of recording the position . . . . of the Erratic Blocks of England and Wales . . . . , Rep. Brit. Assoc. for 1876, pp. 110-114. Davis, D. C.—On the Relation of the Upper Carboniferous Strata. of Shropshire. and Denbighshire to Beds usually described as Permian. Quart. Journ. Geol. Soc., vol. xxxiii., pp. 10-28, pl. 1. (Sections). Hvuenxs, Prov. T.. McK.-—On the Silurian Grits of Corwen, North Wales, Quart. Jown. Geol. Soc., vol. xxxiii., pp. 207—212. (2 woodcuts.) ” Mackinroso, D.—-On a Number of New Sections around the Estuary of the Dee which exhibit Phenomena having an important bearing on the Origin of Boulder Clay, and the Sequence of Glacial Events. Quart. Journ. Geol. Soc., vol. xxxiii., pp. 730-739. (3 woodcuts.) ; .—Mr. Durham on Kames, and Mr. Mellard Reade on Boulder Clay. Geol. Mag., dec. ii., vol. iv., pp. 94, 95. nis Mravz, R.—The Coal, and Iron Industries of. North Wales. Mining Journal, vol. xlvii. (Ang. 19; Sept. 1). _ 71 Monroy, G. H.—The Glacial Strie of the Country around Liverpool. Proc. Liverpool Geol. Soc., vol. iii., pt. 111.; pp. 284-291. ~,—The Carboniferous Limestone and Millstone Grit of Llangollen. mo” p. 299-325. Abstract in Rep. Brit. Assoc. for 1877, Sections, pp. 74, 1878. ___Anstep, Pror. D. T.—Water and Water Supply . . . . Surface Waters. 8vo. London. ch. vi. Crosskry, Rev. H. W.—Fifth Report of the Committee appointed for the rage of "recording the position . . . . of the Erratic Blocks of gland and Wales . . . . Rep. Brit. Assoc. for 1877, pp. 81-90. Morron, G. H.—The Gathonitarons Limestone and Millstone Grit of Llangollen, (Continued). Proc. Liverpool Geol. Soc., vol. iii., pt. Iv., pp. 371-428. Watxer, A. O.—Notes on Lower Coal Measures between Bagillt and Holywell. Proc. Chester Soc. Nat. Science, No. 2, pp. 9-12. 1879. Hueues, Prov. T.. McK:—On the Silurian Rocks of the Valley of the Clwyd. Quart. Jowrn. Geol. Soc., vol. xxxv., pp. 694-698. (2 woodcuts, sections. ) Macxintosu, D.—Results of a Systematic Survey, in 1878, of the Direc- tions and Limits of Dispersion, Mode of Occurrence, and Relation to Drift Deposits, of the Erratic Blocks or Boulders of the West of England and East of Wales, including a Revision of many yéars’ previous Observations. Ibid., pp. 425-455. Map (of Boulder dispersion). Morrow, G. H.—The Carboniferous Limestone and Cefn-y-fedw Sand- stone of the Country between Llanymynech and Minera, ‘North Wales. Pp. 140. 6 plates and 10 woodeuts. 8vo. London. Ruppy, T.—On the Cambrian and Silurian in North Wales. Awad Journ, Geol. Soc:, vol. xxxv., p. 475. SurussoLe, G. W.—A Review of the British Carboniferous Fenestellide. Quart. Journ. Geol. Soc., vol, xxxv., p. 275. Srranan, A.—On some Glacial Strize on the North Wales Coast. ‘Prog. Liverpool Geol. Soc., vol. iv., pt. 1., pp. 44-46. a —Beskited in ‘Plintshire. Geol. Mag., dec. ii., vol. vi., p. 334. ——-, and A. O. WaALKER.—On the Occurrence of Pebble pwith Upper Ludlow Fossils in the Lower Carboniferous Conglomerates of North Wales. Quart. Jowrn. sag Soc.,. vol. xxxv., pp. 268-274. (Woodcut, section), ¢ aj ie € 1880. Esxriccu, R. A.—Notes on Human Skeletons and Traces of Human Workmanship found in a Cave at Llandudno. Proc. Liverpool Geol. Soc., vol. iv., pt. 1. pp. 153-155. Memorandum on the Remains found in the Cave by Pror. Ww. B. Dawkins, pp. 156-159. Everett, -Pror. J. D.—Thirteenth Report of ‘the Committee . appointed for the purpose of investigating the Rate of Increase of Under- ground Temperature . . Rep. Brit. Assoc. for 1880, p. 26. Marr, J. H.—On the Cambrian. (Sedgw.) and Silurian Beds of the Dee Valley, as compared with those of the Lake District. Quart. Journ. Geol. Soc., vol. xxxvi. spp: 277-284. (Woodcut). TEAL, J. J. H.—Origin of the Rocks and Scenery of North Wales. Mid. Nat., vol. iii., pp. 214-219, 237-241, and 266-269. Wuiraker, W.—List of Works on’ the Geology, Mineralogy, and Paleontology of Wales (to the end of 1873.) Rep. Brit. Assoc. for 1880, p: 397. 1881, ‘Acton, E. H.—Subdivisions of the Carboniferous Limestone in Denbigh- shire, North Wales. Rep. Rugby School Nat. Hist. Soc. for 1880, p. 4. Davies, D. C.—A Treatise on Metalliferous Minerals and Mining, pp. 488. gnd edition. 8v0. London. 72 Hicxs,.H.—On the Discovery of some Remains of, Plants at the Base of the Denbighshire Grits, near Corwen, Ni orth Wales; with,an Appendix, by R. Hrueriver. Quart. Journ. Geol. Soc., vol. xxxvii., pp. 482-496. . pore xxv.; (woodcut, section). , Hurt, Pror. E.—The Coalfields of Great Britain ; ftiet History, Structure, and Resources. . . . 4thHd. 8vo. London. pp. xviii., 556. Macxivrosn, D.—On the precise Mode of Accimulation and Derivation of the Moel Tryfan Shelly Deposits; on the Discovery of similar High-level Deposits along the Eastern Slopes of the Welsh Mountains; and on the Existence of Drift-zones, showing probable, Variations i in the Rate of Sub- mergence. Quart. Jowrn. Geol. Soc., vol. xxxvii., pp. 851-369. (3 woodcuts.) Morton, G. H.—On the Carboniferous Limestone of Gower, compared with that of North Wales, Proc.. Leewenggant. Geol. Soc. 7 Beas. 22, vol..iv., pt. 11., pp. 201-209. —— .—List of Papers on’ the Geology of the Country | around Liverpool from 1870 to June 1881; 5 With some additions to the List published in 1871. Tbid., p. 287. ' SHRUBSOLE, G. W.—Farther Notes ‘on the ‘Carbériferots Fonestallidss. Quart. Journ. Geol. Soc., vol. xxxvii., p. 178. Stirrvr, Marx.—On the Glacial Geology of the District of Llandudno, with especial reference to the Boulder Olay. Trans. Manchester Geol. Soc., rare , pt. vul., pp. 172-186. (Figure.)’” Discussion, pt. xI., pp. 243-247, 1 1882. Chom: Rev. C.—Geological, Features of Walesin “ “The Gossiping Guide to Wales” (by AsKEw Roserts). vo. London and Oswestry, pp. xxvii-xli. Everett, Pror. J. D.—Fourteenth Report of the Committee . . . appointed for the purpose of investigating the Rate of Increase of Under- ground Temperature. Rep. Brit. Assoc. for 1881, p. 90. Dz Rance, C.E.—On the Occurrence of Manganese and Hematite at Nant Uchaf, near Abergele, Denbighshire,.in Old Red Sandstone or Carboniferous Basement Beds. Trans. Manchester Geol. Soc.,:vol. xvii., p. 47, and Colliery Guardian, vol. xliii., p. 895. “The Water Supply of England and Wales. 8v0. Lon- don. (Chap. xxviii.) Harrison, W. J.—Geology: of the Counties of. England sal of N orth and South Wales. 8vo. London. . (Pp. 322-342.) . — , ——.~—Geology of L andudno and Rhyl. Knowledge, vol. ii., pp. 305, 306, 337. - - Hicks, H.—Additional Notes on iia Land Plants from the Beniyapicg Slate Quarry, near Corwen, North. Wales. Quart. Journ. Geol. Soc., vol. xxxviii., p. 97. Houenes, Pror. T. McK., and Mrs. W. Wynne. —The Results of recent ‘further ‘Excavations in the Caves of Cefn, near St. Asaph, North Wales. Rep. Brit. ‘Assoc. for 1881, p. 700. Foster, Dr. C. Lz Neve. —On the Oudamence of Cobalt Ores in Flint ‘ghire. , Trans. Roy. Geol. Soc. Cornwall, vol. x., pt. Iv., pp. 107-112. Macxintosn, D.—Additional Discoveries of High-level Marine Drifts in North Wales, with Remarks on Driftless Areas. Quart. Journ. Geol. Soc., vol. xxxviii., pp. 184-196. .. Muapz, R.—The Coal and Iron Industries of the United Kingdom, comprising Descriptions of the Coalfields, Analyses ‘of the Coal and Ironstone, with their production and distribution; also the Rise and Progress of Pig-Iron manufactured i in Great Britain since the year 1740. Map. London. Morton, G. H.—On the Strata between the Carboniferous Tineahonis and the Coal Measures in Denbighshire and Flintshire. Trans. Manchester Geol. Soc., vol. xvii., p. 74. ee 1883. Daviss, D. C.—The Metalliferous Deposits of Flintshire and Denbigh- shire. 8vo. London. 73 Dz Rancz, C. E.--Notes on Geological Sections within Forty Miles Radius of Southport. Rep. Brit. Assoc. for 1883, p. 489; and Geol. Mag., dec. ii., vol. x., p. 500. _Gnirrita-Boscawey, A. 8, J.—The Geology of Denbighshire and Flint- shire. Rep. Rugby School Nat. Hist. Soc. for 1882. Marr, J. H.—The Classification of the Cambrian and Silurian Rocks, being the Sedgwick Prize Essay for the Year 1882. 8vo. Cambridge. Morton, G. Th The Carboniferous Limestone and Cefn-y-fedw Sand- stone of Flintshire. Proc.-Liverpool Geol. Soc., Sess. 23, vol. iv., pt. 1Vv., pp. 297-320; and pt. v., p. 381. 1884, Horrr, H.-—Die Erzlagerstalten von Flintshire und Denbighshire in Wales. Oesten. Zeitschr. Berg.—Hiitt, 1884, pp. 95, 112, 123, 144. Hunt, R.—British Mining. A Treatise on the History, Discovery, Practical Development and Future Prospects of Metalliferous Mines in the United Kingdom, pp. xx. and 944. (Roman Mining in Wales, pp. 25, 29, 37, 39, 41. Flintshire and Denbighshire Geology, 261, 262. Flint- shire veins, 322-324. Minera Mines, 439-444. Copper Mines, 455, 456, 832). 8vo. London. Saarx, Dr. R. A.—Second Report to the Local Government Board on the Examination of Waters. 8vo. London. (Parl. Papers.) Experiments with Flintshire Waters. ; 1885. Hicks, Dr. H.—On some Recent Researches in Bone-Caves in North Wales. Proc. Geol. Assoc., vol. ix. (No. 1.) p. 1. Reaver, T. Metuanp.—The Drift Deposits of Colwyn Bay. Quart. Jowrn. Geol. Soc., vol. xli., pp. 102-107. Mineral Statistics of the United Kingdom for the years 1882, 1883, 1884. Fol. Lond. Prepared by the Tngpectons of Mines. Reports of H.M. Inspectors of Mines. Fol. Lond. to 1884. Map and Sections of the TaLARcoctr Mine and NeIGHBOURHOOD. By A. STRAHAN. Srction No. 1. Showing the Distribution of the Ore in the Talargoch Vein. S.S.W. Crosses Section No. 2. N.E. Draw- Water- Ea- Smed-: Talar- ing Clive wheel gine No.1 ley : goch No.3 Mostyn Shaft. Shaft. Shaft, Shaft. Shaft. Shaft. Shaft.Shaft.: Shaft. ‘ ay é é . Oe a © Walkers “Stat "4 Section No. 2. "Ss In the Dircction of the Dip and across the Veins. - ‘ "3 - q 4 ste W. 33° N. - 6. 33° 8. sy! Hematite and a iS Road. Railway. Graig-fawr. Copper Lode. Road. os . ‘ Bw ore Le OO ae eS Pe oa aes) eG oP Na s ' 1 ee ze, : o Sates > Soe Grdngneé Dy lim es . “f Clive Shatt \ mM YW = - Se : Be OY \— wo 4 eo Ne b Set ae bk ss ‘ S yrs cor IER) Braminig shoe, Pe ee Re, aS MY . oe) 7 . . see), : © ‘i ScaLe for Mav and Sections (Vertical and Horizontal). 6 inches=1 mile. ‘ yg $08 Free ' h ta mile 7 Indicates dip of Strata observed on the Surface. ~ Indicates Alluvium. dive ete o Boulder Clay. wz ” Sand and Gravel. \ : Aneel \" sg eund lt Sie ” » ” Underground. ahh Position of Veins or Faults at the Surface. mark the spots beneath which Underground Temperature has been observed. # Aenotes Glacial Strie. ” ” 7 ” at depth stated INDEX. “ Aberdo limestone,” 15. Abergele, 4, 15, 23, 25, 28, 30, 31, 34, 41, 48, 44, 57. » old lead workings near, 51, 52. Afon Goch, 17. Arenig' Mountains, boulders from, 32, 33. Ash-tree shaft, 51. - Axton, 13, 16, 32. Axton fault, 20. Bala Beds, 2. ' Beekite, 12. Bell, Mr., 41. Birch, Major, 24. Black Limestone, the, 15-18,46, 47, 50. 2 fossils of the, 17. - Blown Sand, 44. Bodelwyddan Church, 14. Bodryddan Park, 31. Bones in the Drift, 33. Boulder Clay, bricks made of, 57. Boulders, 32, 33. Bowman, Mr., 4. Brick-making, 57. Bryn Eurian, 1, 14, 28, 38. Bryn glas, 31. Bryniau, 10. Bryniau Cochion, 4, 11, 14. Buckland, Dr., 29, 30, 33, 56. Cae Gwyn Cave, 34. Cae-llys Vein, 46. Cae’rgwaith, 52. Caerwys, tufa at, 40. Calamine, 45, 48, 49. Capel St. Trillo, 42. Carboniferous Basement Beds, 3-7, 8, 10, 15, 53, 56. Carboniferous Limestone, 7-18. » : ys fossils of, 12, Carreg-y-frdn, 8, 29, 50. ‘Castell Cawr, 14, 15, 28, 51, Cefu Cave, 34. Cefn-yr-ogol, 14, 28, 40, 51, 52. Cerrig Heilyn, 51. Chert Beds, 16, 18-20, 21, 48, 49. s Manganese in ‘the, 45, 46. Chert, encrinital in limestone, 11, 12. China Rake, 47, Cleavage in Wenlock Shale, 2, 3. Clwyd, alluvium of, 40. Coal Commission, 37, A 17240. thickness of, 12. Coal in the Lower Limestones, 9. Coal-measures in the Vale of Clwyd, 20-23, 26, 27, 56. - Cobalt ore, 54, 55. Coed-yr-Esgob, 12. “© Coke,” 48, Colwyn Bay, 1, 6, 28, 34-88, 41, 57. Conway, R., 42. Copper ore, 54-56. Crag Heilyn, 31. Craig, 1, 28, 34, 35, 39. Cwm Iron-mine, 3, 53. Cwm Mountain, 8, 23, 28, 33, 39. Dawkins, Prof. W. Boyd, 34. . Denbigh, 24, Denbigh Grits, 2. Drift, gravel-ore in, 47. ; Drift-transport, direction of, 39. Dulas, valley of the, 14, 15, 35, 51. es 8, 20, 21, 22, 23, 28, 30, 38, Dyer Castle, 8, 10, 31, 47. Dyserth Mine, 23, ms Dyserth Waterfall, 2 East Talargoch Mine, 29; Etheridge, Mr. R., 17. Felin Nant, 40. Ffernant Dingle, 4, 6. Ffos-y-Bleiddiaid, 51, 52. Ffynnon Asaph, 10, 31. Ffynnon Beuno Cave, 34. Foryd Boring, .25, 26, 30, 40, 56, 57, Foster, Mr. C. Le Neve, 54, ' Francis, Mr. Absalom, 50. Fron-y-cwm, 23. Gage, Mr. M. A.,, 10, 52, 54, 55, Garth-gogof, 7. z Gele, alluvium of, 40. Gllderoy, Mr., 27, Glan-y-mor, 37. Golden Grove, 14, 16, 19, 32, 49, 50.: Gop Farm, 32. Gop Hill, 8, 11, 12, 32. Gorddyn mawr, 14. Gravel ore, 47, 49. Graig-fawr, 8, 22, 29, 38, 39, 46~48, 55. Great Orme’s Head, 1. 76 INDEX. - Gronant, 18, 19, 20, 21, 28, 30, 56. Gronant Mine, 49. Gwaenysgor, 11, 16, 17, 32, 38. Gwespyr sandstone, 20, 56. . Gwrych, 15, 23, 51. Hematite, 8, 6, 7, 45, 52-56. Halkin Mountain, 18. Hall, Mr. C. R., 42. Hall, Mr. H. W., 42 Helig, 42. Hendre-fawr, 33. Hendre-mynach, 31, 32, 33. Henfryn, 32. Henfryn, copper ore at, 55. Henfryn hematite working, 54. Hicks, Dr., 34. : Holywell, 16, 17, 18, 20, 48. Holywell Shales, 20. Hope Mountain, 18. ‘Howell, Mr. Joseph, 25. Howell, Mr. Leigh, 18, 25. Hughes, Mrs. T. McK., 35, 41. . a Hughes, Prof. T. McK., 24, 89. Hull, Prof., 27. : Hunt, Mr. Robert, 50, 52, 58, 54. Hydraulic Limestone, 11, 15, 17, 20. Iron-pyrites, Stalagtitic, 23, 51. Isle of Man, Posidonia Schists of, 17. Joint-y-clawdd, 49. Kelston Farm, 20, 32, 49. Lean, Mr., 58. Limestone, analysis of, 10. Little Orme’s Head, 1, 14, 28. Lilanarmon, 18. Llanasa, 16, 18. Llandulas, 4, 15, 23, 24, 28, 30, 34, 35, 89, 40, 57. Llanerch, 24, Llangynhbafal, 26. Llangwystenin, 42. Llysfaen, 4, 14, 35. Loss of land, supposed, 42. Lower Coal ‘Measures, 56. Lower Limestone Shales, 10, 14, I8. Llys Eurian, 38. Llys Helig ab Glanawg, 42, 43. Maes-Elwy, 24. Maes Garmon, 26. Main Joint, 53. Manganese ore, 19, 45, 56. Marian, 9, 11,53. | Marian-bach, 4. Marian Mill, 10. Marsh clay, bricks made of, 57. - Meliden, 8, 11, 12, 16, 20, 21, 22, 29. Min-y-don, 35. Moel Fammau range, drift from, 31. Moel Hiraddug, 8, 9, 10, 23, 28, 38, 52, 54, 55, 56. Moissenet, M., 27, 48, 49. Morfa Llandrillo, 41. Morfa oe 42. Morton, Mz., 7, 8,9, 10, 11, 12, 18, 14, 18, Nant-ganol, 7. Nant-uchaf Mine, 55, 56. Nant-y-mwyn, 16, 19, 50, Nant-yr-ogof, 11. Nickel ore, 54, 55. - Pant-glas, 33. Panton’s Vein, 46, 47. Parry, Rev. R., 42. Peat, 40, 41. Pen-lwys, 6, 14. Penmaen, 1, 6, 28, 35. Pennant, Mr. Thomas, 46, 48.° Pentre-bach, 4, 9. Pentre chert-quarry, 19, 20, 49, 56. Pentre-ewm, 3, 4, 9 Pentre, near Newmarket, 33. Pen-y-cefndy, 30. Pen-y-coed, 7. . Pen-y-corddyn-bach, 15. Pen-y-corddyn-mawr, 7. Pen-y-dared, 4,6. . - Pen-y-Graig, 15. Pen-yr-allt, 15, Pen-yr-allt, near Grnenyarse, 38. Pitch, natura), 48. Plas-newydd, 31. Plas-on-bach, 11. Point of Ayr, 24. Pont-yr.allt-goch, 24. cr uaned: in the Black Limestone, £ Plant-remains in the Lower Limestone, a. Prestatyn, 8, 11, 12, 16, 20, 21, 29, Bly 40, 44, 57, Prestatyn Boring, 27, 29, 56, 57. » Bault, 8, 16, 50, 55, Price, Mr. J.,.4. ° Pyrolusite, 56. Pwil-halog, 31. Pwll-y-crochan, 28. Pwil-y-crochan-isaf, 37, Ramsay, Sir R. A., 2, 24, 30, 34. Rhos, 41, 42, 43. Rhuddlan, 31. Rhuddlan Castle, 24. Rbuddlan Marsh Boring, 27. Rhyd-y-foel, 35. Rhyl, 8, 25, 26, 30, 31, 34, 40, 41, 49, 44, 57. Roman iron- -mining, 52. » _ lead-mining, 46, 59, Round ore, 47, 49, INDEX. 77 St. Asaph, 23, 24, 80, 57. Sandstone, interbedded i in Limestone, 11. Shells in the Drift, 34. Shone, Mr. J. B., 17, 20. Shone, Mr. W., 41. Shrubsole, Mr., 18. Siambr-wen, 14, 15. Siambr-wen fault, 15, 24, 51. Silicified fossils, 12. Silicious vein-stuff, 47, 49, 51. Silver, 45, 49. Smith, Mr. ‘W., 48. Snowdon range, boulders from, 38. South Joint, 46, 47, 48, 58. Staffordshire Potteries, 19, 47, Stags’ horns, 35, 53. Strie, 38. Sulphuretted hydrogen, 22. Talacre Dingle, 20. Talacre Mine, 19, 20, 48-50. ff production of ores from,50. Talargoch, 16, 20, 21, 22, 28, 27, 28, 29, 33, 34, 45-48, 56, 58. Talargoch, production of ores from, 48. Tan-y-gopa, 14, 15. Tan-yr-allt, ‘Meliden, 12, 22. Tan-yr-allt, Prestatyn, i, 12. Tan-yr-ogof, 4, 52. Tarannon Shales, 2 Teilia, 17. Terfyn, 16, 19, 50. -Tilestones, 3, 5. Trelogan, 18, 19. Tremeirchion, 34. Trimmer, Mr., 4, 38, 84, 47. Tafa, calcareous, 40, 50, 53. Tyddyn Morgan, 51, 52. Tyddyn-uchaf, 7, 15. Tyddyn-y-cyll, 53, 55. Ty-draw, 33. Ty-mawr, 6, 35. Ty-newydd, 51. Ty’n-rhiw, 38. ‘Ty’n-y-caeau, 7. Ty’n-y-coed, 7. Tyn-yr-allt, Prestatyn, 11, 12, 29. Twynan-uchaf, 6. Upper Ludlow Beds, 3, 5. Vale of Clwyd fault, 8, 21, 22, 23, 56, 58. Veins, distribution of ores in, 45. Volenant Telegraph Station, 50. Walker, Mr. A. O., 4, 20, 58. Walker’s Shaft, cross-cut from, 23. section of, 22, 28, 29. temperature of, 58. Wenlock Shale, 2,3. % overlap of, by the Car- boniferons Rocks, 3, 6. « White Lead,” 45, 49. White sand, 47, 49, Williams, Mr. John, 52. - »” ” Ysgubor-y-coed, 24, Zine Ore, 45. LONDON: Printed by Exr= and Srorriswoonpse, Printers to the Queen’s most Excellent Majesty. For Her Majesty’s Stationery Office. [15301.—500,—11/85.] GENERAL MEMOIRS OF THE GEOLOGICAL SURVEY—continued. ‘The, CARBONIFEROUS LIMESTONE, YOREDALE ROCKS and MILLSTONE GRIT of N. DERBYSHIRE. . By A. H. Geren, Dr. 0. LE NEVE Fosrrr, and J. R.Daxyys. (2nd Ed. in preparation.) The: a ae oe FIELD. By E. Hut, J. R. Daxyns, R. H. Tippeman, J. C0. Wap, W. Gunn, and C. E. es 3. ‘The YORKSHIRE COALFIELD. By A.H. Green, J.B. Daxyns, J. C. WARD, c. Fox-STRANGWAxs, W. H. 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T. CLoveH.) i tt THE MINERAL DISTRICT BY THE FOLLOWING S OF ENGLAND AND WALES ARE ILLUSTRATED PUBLISHED MAPS OF THE CEOLOCICAL SURVEY. fei apn i Dae ee COAL-FIELDS OF ENGLAND AND WALES. : ew” one inch to a mile. Anglesey, 78 a Bristol aa Somerset, 19, 35. Coalbrook Dale, 61 (NE & SE). Slee Hill, 58 (NE, NW). See cah erpiebabiie, 74 (NE & SE), 79 (NE, SE) Durham—coniinued. Sheet. Sheet. 9. 25. Wolsingham. 10. Edmondbyers, 26. Brancepeth. 11, Ebchester. 80. Benny Seat. 32. White Kirkley, 33. Hamsterley. 34, Whitworth. 12, Tantoby. 13. Chester-le-Street. 16. Hunstanworth. 49, Laneshaw Bridge. &5, Whalley. 56, Haggate. 57. Winewall. 61. Preston. 62. Balderstone, &c, 68. Accrington. 64, Burnley. 65. Stiperden Moor, 69, Layland. 70. Blackburn, &c. 71, Haslingden. "2, Cliviger, Bacup, &c. 78. Todmorden. 77, Chorley. 78. Bolton-le-Moors. 79. Entwistle. 80. Tottington. 81. Wardle. 1. Ryton. 2. Gateshead, 3. Jarrow. 4, 8. Shields. Embracing the produce of Coals, Metallic Ores, i 1s. 6d.each. 1858, Part I, 1s. 6d.; i eae otner tones By ee 1868.28. 6d. 1864, 2s. 92. Bickerstaffe. Flintshire an ). ‘Derby and Yorkshire, 71 (NW, NE, & SE), 82 (NW &S8W), 17. Waskerley. 38. Maize Beck. 81 (NE).87 (NE, SE), 88 (SE). 18. auanel srs 41. Cockfield. Forest of Dean, 43 (SE & SW). 19. Lanchester. 42. Bishop Auckland, oreat of Wyre, SL Su), 55 (NE). 20. Hetton-le-Hole. 46. Hawksley Hill House. Lancashire, 80 (NW),81 (NW), 89,88 (SW, NW). 92, Wear Head. 52. Barnard Castle. Leicestershire, 71 (SW), 63 (NW). 23. Eastgate. 53. Winston. ‘Northumberland & Durham, 103, 105,106 (SE), 109 yey 24, Stanhope. N. Staffordshire, 72 (NW), 72 (8W),73(NE),80 (SE), 81(5W). Worthumberland 8. Staffordshire, 54 (NW), 62 (SW). ‘o rb x Shrewsbury, 60 (NE), 61 (NW & SW). 44, Rothbury. 80. Cramlington. 98. Walker. South Wales, 36, 87, 38, 40, 41, 42 (SE, SW). 45 Longframling- 81. Earsdon. 101. Whitfield, Warwickshire, 62 (NE SE), 63(N W SW). 54 (NE) 58 (NW). 4a, a ay she Sane. ae: Mengals i 2, 9 . il. » Coadie: ie. ‘own. Yorkshire, 88 (NE, SE), 87 (SW), 92 (SE), 93 ( ) 47, Coquet Island. 87. Heddon. 103. Slaley. e Toners Y= = dene peneONs 105. Rewinnds. ji » Ulgham. * . Tynemouth. 106. Blackpool Br. GEOLOGICAL MAPS. 56. Druridge Bay. 9t. Greenhead. 107. Allendale, Scale, six inches toa mile. 63. Netherwitton. 92. Haltwhistle. 108. Blanchland. The Coal-ficlds and other mineral districts of the N._ of 64. Morpeth. 93. HaydonBridge. 109. Shotleyfield. England are published ona scale of six inches to a mile, €5, Newbiggin. 94, Hexham. 110. Wellhope. at 4s. to Gs.each. MS. Coloured Copies of other six-inch 72. Bedlington. 95. Corbridge. 111. Alenheads, maps, not intended for publication, are deposited for refer- 73. Blyth. 96. Horsley. 112. ence in the Geological Survey Office, 28, Jermyn Street, 97. Newcastle. London. Cumberland. 55. Searness. 69. Buttermere. Lancashire. 56. Skiddaw. 70, Grange. Sheet. Sheet. 63. Thackthwaite. 71. Helvellyn. 15. Ireletix. 84. Ormskirk, St.Johns, &c. 64. Keswick. 74, Wastwater. 16, Ulverstone, &s. Btandish, hs. fe 65. Dockraye. 75. Stonethwaite Fell. 17. Cartmel. 6. ington, Horwick, &c. 22, Aldingham. 87. Bolton-le-Moors. ‘Westmorland. 47. Clitheroe. 88. Bury, Heywood. 2. Tees Head. 12. Patterdale. 25, Grasmere, 48. Colne, Twiston Moor 89. Rochdale, &c. 6. Dufton Fell. 18. Near Grasmere. 38. Kendal. Yorkshire. 93. Wigan, Up Holland, &c. , 94. WestHoughton, Hindley. 116. Conistone 260. Honley. 95. Radcliffe, Peel Swinton. 7. Redcar. Moor. 261. Kirkburton. 96. Middleton, Prestwich. 9. 183. Kirkby 262. Darton. ~ 97. Oldham, &e. 12. Bowes. __ Malham. 263. Hemsworth, 100. Knowsley, Rainford, &c. 13. Wycliffe. 184. Dale End. 264, Campsall. 10L Billinge, Ashton, &c. , 20, Lythe. 185. Kildwick. 272, Holmfirth. 102. Leizh, Lowton. 24, Kirkby Ravens- 200, Keighley. 273, Penistone. 103. Ashley, Eccles. worth. 201. Bingley. 274. Barnsley. 104. Manchester, Salford, &c. | 25: Aldborongh. 202, Calverley. 275. Darfield. 105. Ashton-under-Lyne. 32. Whitby. 203. Seacroft. 276. Brodsworth. 106. Liverpool, &c. : 33. 204. Aberford. 281. Langeell. 107. Prescott, Huyton, &c. 38, Marske. 215. Peeke Well. 282, Wortley. 108. St. Helen’s, Burton Wood. 39. Richmond. 216. Bradford. 283. Wath upon 109, Winwick, &c. Baie nas ,_ 217. Calverley. Dearne, 111. Cheedale, Stockport, &c. 47, Robin Hood’s 218. Leeds. 284, Conisborough. 112, Stockport, &c. Bay. 219, Kippax. 287. Low Bradford. 118: Part of Liverpool, &c. 58. Downholme. 231. Halifax. 288. Ecclesfield. 68. Leybourne. 232. Birstal. 289. Rotherham. 82. Kidstones. 233. East Ardsley. 290. Braithwell. urham. 84. E. Witton. 234. Castleford. 293. Hallam Moors, s 97, Foxup. | 246. Huddersfield. 295. Handsworth 5. Greenside. 98. Kirk Gill 24 . . ea irk Gill. 7. Dewsbury. 296. Laughton -en- . Winlaton. 99. Haden Carr. 248. Wakefield, le-Morthen. 7. Washington. 8. Sunderland 100. Lofthouse, 115, Arncliffe. 244. Pontefract. 250. Darrington. 299, 300. Harthill. MINERAL STATISTICS. Part If, 6s. 1859, 1s. 6d. 1865, 2s. 6d. 1866 to.1881, 26. each. Hunt. From 1858 to 1857, inclusive, 1860, 8s. Gd. 1861, 2s.; and Appendix, 1s. 1862, 2s. 6d.. (These Statistics are now published by the Home Office, as parts of the Reports of the Inspectors of Hines.) Sate ae one ORES OF GREAT BRITAIN. art I. The North an orth Midland Counties of England (Out int). ‘ ire. i Part 111. South Wales. Price 1s. 8d. Part IV. The Simutite Genoa Pere Suadordanine ase sae eee ae LG € GUGEE COU T