68 ON THE COAL AND IRON MINING OF SOUTH YORKSHIRE. -- Br MR. PARKIN JEFFCOCK, OF DERBY. -- It is proposed in the present paper to consider the general features of the South Yorkshire district with reference to the circumstances affecting mining engineering. The accompanying general plan, Fig. 1, Plate 19, represents that portion of the Yorkshire coalfield which is more particularly called the South Yorkshire district; extending from Sheffield on the south to Wakefield on the north about 25 miles, and from west to east about 20 miles altogether, on either side of Barnsley. The plan shows the general extent of the coalfield, indicated by the shaded portion ; the outcrops of two of the principal seams of coal, the Silkstone and the Parkgate seams ; the positions of the principal faults ; the localities of the more important collieries and ironworks; and the lines of railway and water conveyance. The horizontal section, Fig. 2, Plate 20, which is reduced from the late Mr. Thorpe’s published section, is taken through Barnsley along the dotted line W E upon the plan, Fig. 1, extending from the millstone grit on the borders of Derbyshire on the west to the eastern boundary of the coalfield at E. The vertical section, Fig. 3, Plate 21, represents the position and thickness of the principal beds of coal and mines of ironstone, as they were proved by borings at Wath Wood, near Lundhill Colliery on the plan, Fig. 1. Five beds of coal, between the Woodmoor seam and the Kent’s Thin seam, do not occur at this place j a second vertical section, Fig. 4, is therefore placed alongside, showing these beds in their corresponding position as they were proved in sinking at the Oaks Colliery near Barnsley, Fig. 1. Downloaded from pme.sagepub.com at University of Bath - The Library on June 5, 2016 SOUTH YORKSHIRE COAL MINING. 69 The South Yorkshire coalfield is a continuation northwards of the Derbyshire coalfield. On the east it is bounded by the overlying and unconformable magnesian limestone and permian strata, and the extent of the coal measures in this direction is yet unproved. On the west the millstone grit rocks crop out, forming the bleak moors of North Derbyshire; and the coal measures extend northwards and constitute the North Yorkshire coalfield. The general dip of the coal strata is from west to east at an average angle of 1 in 9 j this however is much modified in many locqlities by main faults, the principal of which are shown on the plan, Fig. 1, by the strong black lines. The total number of coal seams is very great, as shown in the vertical section, Fig. 3, and many of them have been worked in various localities. The following are the principal seams of coal in their geological order, with their average thickness :- 1. Wath Wood or Muck seam ......... 4 ft. 6 ins. thick. 2. Coal, no name ............ 3 8 3. Woodmoor seam ............... 3 0 4. Winter seam ............... 5 4 5. Upper Beamshaw seam ............ 4 8 6. Lower Beamshaw seam ......... 2 2 7. Eent's Thin seam ............ 2 r 8. Kent's Thiok or High Hazel seam ...... 5 0 9. Barnsley Thick seam ...... 8 ft. 6 ins. to 9 0 10. Swallow Wood seam ............ 5 0 11. Howard or Flockton seam ......... 5 0 12. Fenton's Thin seam ............ 2 3 13. Parkgate or Chapeltown seam.. ....... 6 0 14. Thorncliffe Thin seam ......... 2 6 15. Four Foot seam, variable ......... 4 0 1G. Silkstone or Sheffield seam ......... 5 0 17. Charlton Brook or Mortomley seam ...... 3 0 The most important seam of the series is the Barnsley Thick coal, which under the name of the Main or Top Hard coal has been very extensively worked in Derbyshire. In the South Yorkshire district its average thickness is about 8 feet 6 inches, but the thickness varies exceedingly at different places. It is most fully developed in the neighbourhood of Barnsley, but extends through the greater part of Downloaded from pme.sagepub.com at University of Bath - The Library on June 5, 2016 70 SOUTH YORKSHIRE OOAL MINING. the district, and has been principally worked at Woolley, Gawber, The Oaks, Edmund’s Main, Wombwell Main, Darley Main, Elsecar, Warren Vale, Rawmarsh, Hoyland, Lundhill, Mount Osborne, Thryburgh, Darfield, Car House, &G. The hard coal from this seam is in great repute for steam purposes, and stood high at the trials made at Woolwich in 1851 relative to the value of steam coals. North of Woolley the Barnsley seam is subdivided into two or three others, which are worked in the neighbourhood of Normanton under different names. In Derbyshire it appears to the best advantage at the large works of Mr. Barrow at Staveley, where it is known as the Staveley Hard coal, which has been extensively used for steam purposes and in the manufacture of iron. The Swallow Wood seam occurs about GO yards below the Barnsley Thick coal, its thickness varying from 3 feet 4 inches to G feet. It has been worked only to a very limited extent, principally at Swallow Wood; and is known in Derbyshire as the Dunsil or Oldgreaves coal, lying there about 30 yards below the Top Hard seam. The Parkgate or Thorncliffe Thick seam occurs at an average depth of 219 yards below the Swallow Wood, and has been chiefly worked at Parkgate, Thorncliffe, Pilley, &c. Its average thickness is 5 feet 6 inches, but the thickness varies considerably from 4 feet 10 inches to about 6 feet. It is known as the Bottom Soft coal in Derbyshire, where it has heen very extensively worked. The Thorncliffe Thin seam, called the Bottom Hard in Derbyshire, is found 24 yards below the preceding ; its thickness is from 2 feet G inches to 3 feet, and it has been principally worked at Thorncliffe, Pilley, &c. The Silkstone or Sheffield seam lies about 61 yards below the Thorncliffe Thin, and has an average thickness of about 5 feet. It is a very well defined seam, and may be taken as a sort of datum line in identifying the position of the other beds. It has been principally worked in the neighbourhood of Sheffield, and at Chapeltown, Thorncliffe, Pilley, Mortomley, and 8illrstone ; and is identical with the Blackshale or Clod coal of Derbyshire. The coal is of great value for house fire purposes, competing with the celebrated I-Ietton Wallsend. Downloaded from pme.sagepub.com at University of Bath - The Library on June 5, 2016 SOUTH YORHSHIRE COAL MINING. 71 By far the most important and valnable of the seams of coal are the Barnsley Thick and Silkstone seams. At the Woolwich trials made by the admiralty in 1851 relative to the strength and value for steam purposes of the Barnsley Thick coal from Darley Main, West Hartley coal from Newcastle, and Welsh coal from Merthyr Tydvil, the total weight of water evaporated in each case was 24,960 Ibs., and the evaporation per lb. of coal was 8.10 lbs. by the Barnsley Thick and West Hartley coals, and 8.25 lbs. by the Merthyr coal. Trials were also made of the Barnsley Thick coal in 1858 at Doncaster on the Great Northern Railway, when the evaporation obtained was 7-64 Ibs. of water per Ib. of coal, the total weight of water evaporated being 448,281 lbs., and the coal used being a mixture of steam coal and house fire coal consumed under Cornish boilers working at a pressure.of 45 lbs. The Barnsley Thick coal light8 easily, burns freely, and raises steam rapidly. It produces only a very small quantity of white ashes and cinders, giving little trouble to the stokers, and the less it is disturbed the better; it does not clog or adhere to the bars, and makes no slag, maintaining a good clear fire with little sulphur. It is a most economical coal for marine engines, and in using it a light thin fire is particularly recommended. The mines of Ironstone occur between the Barnsley Thick coal and the Silkstone coal, as shown in the vertical section, Fig. 3, Plate 21. The first mine of importance is the Swallow Wood, about 60 yards below the Barnsley Thick coal, which has been principally worked at Milton for the supply of the furnaces there. It consists of three measures of ironstone, and an analysis of a sample of the ore by Mr. Spiller of the Geological Museum gave 26.79 as the percentage of metallic iron. The Lidgate mine, next below the Swallow Wood, has been extensively worked at Milton, Tanlrersley, and Thorncliffe. The Tanlrersley mine is usually found about 50 yards below the Lidgate, and is called also the Musselband ironstone from the number of fossil shells it contains. It has been worked chiefly at Tankerslep, and yields about 1500 tons of ironstone per acre. 11 Downloaded from pme.sagepub.com at University of Bath - The Library on June 5, 2016 72 SOUTH YORKSHIRE COAL MINING. The Thorncliffe Black mine lies about 70 yards below the Tankersley: it is worked principally at Parkgate, and used in the furnaces at Milton and Elsecar j and an analysis by Mr. Spiller gave 34.16 per cent. of metallic iron. The Thorncliffe White mine lies immediately below the Parkgate Beam of coal, and consists of three measures, containing about 32 per cent. of metallic iron and yielding about 1500 tons of ore per acre. It has been worked principally at Parlrgate and Thorncliffe, and was formerly worked extensively at the Holmes. The lowest mine is the Clay Wood or Black mine, consisting of three measures, containing about 32 per cent.