MINE. 



353 



Coal 



PLATE 

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 ?'( '-' 



PLATE 



F- ** 



r sity, but they can be crept through to a great distance. 

 There are two principal modes of carrying on the 



""* Shropshire system. 



juf The first, or what is properly the original system, 

 was to open out the wall in the manner before de- 

 scribed around the pit-bottom ; and as the wall- 

 race extended in width, to set off main-roads nnd 

 branches, very much in the form of the branches of 

 a tree ; these roads were so arranged, that betwixt the 

 ends of any two branches there should be a distance of 

 from 90 to 40 yards, according as might be ost 

 suitable, as represented in Fig. 2. Each space of coal 

 betwixt the roads is named a wall ; ami one half of 

 the coals produced from each wall is carried to the one 

 road, and the other half to the other road ; this is a 

 gnat conveniency when the roof is bad, so that in 

 many instances the distance of 20 yards betwixt the 

 roads is preferred. In the figure, A is the pit, BB the 

 wall-face, a the dip-head level, t> the roads at from 20 

 to 4O yards asunder, a the gobb or waste, with 

 buildings along the sides of the roads, and d the pil- 

 Ian. 



The other Shropshire method is represented in Fig. 

 14, Plate I. where A represents the pit with 



the bottom pillars ; b the dip- hew I levels ; c the off- 

 break from the level, where no pillars are left ; rf the 

 off-break, where pillars are left to secure the level. All 

 roads are secured in the sides by buildings of stone, 

 if such can be had, kid off 9 feet wide. After the 

 crush settles, the roads are generally permanently good, 

 and can frequently be travelled through as easily fifty 

 years after they have been made, as at the first When 

 stones cannot be hail in abundance, coal* have to be 

 used, and are built about 20 inches in the base. If 

 schist is used, it requires to be from 2 to 3 feet square. 

 In this method, the roads are also from 20 to 40 yards 

 apart, bat in place of branching they are set off in a di- 

 rection parallel to each other. The workmen secure 

 the waste by gobbing ; and three rows of props are 

 carried forward next the wall faces a, with pillars of 

 stone or coal built betwixt them. This mode is more 

 regular than the formrr, though not in such general 

 practice. 



The coal, when wrought in the Shropshire method, 

 is carried on by the workmen very differently from the 

 post and stall system, where each man has his own 

 room, and performs all the labour. The Shrop-hirc 

 method i* carried on by the division of labour perform- 

 ed by different sets of workmen, generally divided into 

 three companies. The first set, curves or pools the 

 along the whole line of walls, laying in or pool- 

 ing always at least 3 feet, and frequently 4.' inches, or 

 five quarters, s< they term it. Their work is measured 

 MS to length and depth by the overman, the depth being 

 gauged by in iron instrument, named a jack, 40 inches 

 long, the knee of which must reach the wall face, if 

 the> full; if short, the workman must com- 



plete it These men are named Holer*. As the crash 

 is constantly following them, nnd working over their 

 head*, which frequently has the effect of making the 

 coal f*ll above them, for their security, props of wood 

 are set at regular distances in an oblique direction be- 

 tween the pavement and wall face. Besides these, for 

 farther -ecurity, staples of coal, about 10 inches square, 

 are left at evvry 6 or 8 yanN dinner, until the line of 

 < or curving ,., <., ,vtel. The walls are then 

 divided into -pace* of from (i to 8 yards in length ; and 

 hearing or perpendicular cut 

 is made . deep a, the holing, and when this u done, the 



VOL. XIV. PART I. 



holer's work is completed. The next set of men who sue- Mint* of 

 ceeds the holers are the getters. These begin at the ^' t *' 

 divisions of wall at the centre, and drive out the gibbs ^~. ' ~, 

 and staples. The)- then set wedges along the roof, and co ^ r 

 bring down each division of coal progressively ; or, if 

 the roof is very bound, the coal is blown down with 

 gunpowder. It frequently happens, when the roof has a 

 good parting, the coals tali down the instant the gibbs 

 are ..truck, which renders the work very easy. The 

 getters are relieved by a third set. of men, named buttv- 

 imn. who break out the coals into pieces of a proper 

 size for sending up the pit, and have the charge of turn- 

 ing out the coal from the wall face to the ends of the 

 road*. When this is done, they build the stone pillars, 

 fill up the gob, set the trees, clear the wall faces of all 

 obstructions, set the gibbs, nnd have every thing clear 

 and patent for the holers recommencing their work. 

 If the roads are to heighten, by taking down the roof, 

 or lifting the pavement, these butty-men perform thi-, 

 work also, build, forward the sides of the roads, and se- 

 cure them with props when necessary. When both 

 pavement and roof are hard, and the coal above 4 feet 

 thick, a greater proportion of coal ic lost by securing 

 the waste, than when the pavement is moderately hard, 

 or the roof easily taken down, as these afford plenty 

 of gobbing. Frequently nothing but the large pieces of 

 coal are taken out for the market, all the smaller parts 

 of the coal and culm being required for the gob, besides 

 a proportion of the great coal for the small pillars. 

 >' hen a coal has a following or roof stone, which cemes 

 regularly away with the coal, this renders the work 

 easy, and saves much coal ; and when it happens that 

 a soft bed of fire clay is found a foot or two under the 

 sole of the coal, the holing is made in it, and the stone 

 betwixt the holing and the coal benched down, which 

 serves for pillars and gobbing. By this plan all the 

 vendible coal is saved. 



The chief caution required in the management or 

 conducting the Shropshire method, is the off- break 

 from the pit bottom nnd levels, to produce the first 

 break of the strata ; the more the waste is filled with 

 gobbing, the less is the risk of any misfortune to the 

 works or the miners. When the superincumbent strata 

 are strong, with thick beds ot sandstone near the coal, 

 the waste will sometimes advance many yards before 

 the break takes place ; and when it commences, which 

 is known by the great noise heard over head, the 

 greatest care is required, to prevent the crush making 

 a break, or nipping along the face of the whole wall, 

 which sometimes happen*. This is termed iht mil 

 coming in ; that is, the strata come down along the 

 whole line of the wall faces, and shut up every open- 

 ing. The consequence of which is, that tin- faces have 

 all to be opened out again along the line of the break, 

 and to the rise of the broken rock face. (', during the 

 (MUM. of the ordinary working, when the crush comes 

 regularly and progressively forward, care is not taken 

 to keep the gob well and regularly filled up, in the man- 

 ner already mentioned, the coming in of the wall is al- 

 most the certain consequence. 



As to the setting of props, and the building of pillars 

 in this work, if the roof and pavement are both very 

 strong, the pillars of stone are built as usual, but not 

 made very firm by any kind of wedging ; and in place 

 of setting the props firm betwixt the root und pavement, 

 it is of advantage to place under each a bit of stone, or 

 small piece of waste wood, the object here not bring to 

 resist the absolute pressure of the strata, but to keep up 

 the roof stone for the safety of the men, until the strata 

 2 v 



