36S 



MINE. 



Mines of 

 Coal. 



Spedding'a 

 invention 

 ami great 

 improve- 

 ment. 



Distribu- 

 tion of the 

 air. 



'PLATE 

 cccxciv. 

 Fig. 8. 

 Coursing 

 the air. 



The ventilation of coal-mines, where inflammable air 

 abounded, was conducted on the old principle of ven- 

 tilating only the fore-heads and wall- faces, where the 

 men were at work until the year 1760. The conse- 

 quence of which was, that the process being irregular 

 and uncertain in its operation, the accidents from ex- 

 plosions were frequent and fatal. To obviate these 

 misfortunes, the ingenious Mr. Charles Spedding, a 

 native of Cumberland, contrived and brought into 

 practice the present system of ventilation, that is, he 

 converted each room, board, or mine, as soon as it was 

 formed, into an air course ; by which means, he not 

 only ventilated the wall-faces where the miners wrought, 

 but also the whole extent of the old wastes. This was 

 a very great and important improvement, and the 

 mining interests of Great Britain have been highly be- 

 nefited by it. To the memory of Mr. Spedding every 

 tribute of respect is due. 



The general system, as to the distribution of the air, 

 after passing down the downcast shaft, is to give the 

 first of it to the stables where the horses are kept, then 

 to the workmen in the foreheads, when the air, load- 

 ed with what mixtures it may have received, traverses 

 the old wastes ; and, lastly, passing over the furnace 

 with all the inflammable air found in its course, ascends 

 the upcast shaft, and is dissipated in the common 

 air. 



Mr. Spedding's system is termed, " coursing the air ;" 

 and according to the abundance of the inflammable air 

 in the mines, the coursing is either conducted up one 

 room, and returned by the next alternately, through 

 the whole extent of the works ; or two or three rooms 

 are connected, so that the air passes up two or three 

 rooms, and returns by the same number alternately as 

 above mentioned. 



This most ingenious system has been greatly im- 

 proved by the mining engineers of the Newcastle and 

 Whitehaven districts collectively ; and, in particular, 

 by Mr. Buddie before mentioned, who, in his report 

 upon the ventilation of coal-mines, has shewn in a very 

 clear and explicit manner, the result of an extensive 

 practice, the manner of applying the system effectually, 

 and of guarding those points when the greatest danger 

 is likely to arise. Several of the following remarks 

 and examples are taken from that report. 



The improved system of ventilation upon an extend- 

 ed scale, by which the current of air sweeps every cor- 

 ner of the workings, is represented, Fig. 2. Plate 

 CCCXCIV. where a is the downcast, and b the up- 

 cast shaft. By following the course of the arrows, it 

 will be seen, that the air passes first along the two 

 rooms r, d, having free access to each through the 

 walls, but is prevented from entering into the adjoin- 

 ing rooms by the stoppings which form the air cour- 

 ses : it sweeps the wall faces of the rooms c, d, and 

 makes a return down the rooms e,f, but is prevented 

 from proceeding farther in that direction, by the stop- 

 pings g, h ; it proceeds to the foreheads i, k, and single 

 courses all the rooms to the foreheads /, m ; at this point 

 it would go directly to the upcast pit 6, if it were not 

 prevented by the stopping n, this throws it again into 

 double coursing the rooms, until it arrives at o, when 

 it goes direct to the furnace, and ascends the shaft b. 

 The lines across each other, represent the passing doors ; 

 and these may be substituted in any place for a pas- 

 sage where there is a stopping. The stopping p, near 

 the bottom of the downcast shaft, is termed a main 

 stopping, because, if it was removed, the whole circula- 

 tion would instantly cease, and the air, in place of tra- 



versing in the, direction of the arrows, would go direct- Mines of 

 ly from the downcast pit a, to the upcast pit b, along <: ^' , 



the mine q. The consequence of which would be, ^"TX""*' 



. ~ i . , Ventila- 



every mine and room of the workings would be laid , ion< 



dead, as it is termed, and be instantly filled with in- 

 flammable air, which, if not guarded against, would 

 either fire at the miner's candles, or at the furnace next 

 the upcast pit b. In the same manner, a partial stag- 

 nation in a district of the colliery, would be produced 

 by any of the common stoppings being removed or de- 

 stroyed by accident, as the air will in that case always 

 take the nearest course to the upcast pit. Main stop- 

 pings are made very secure, by strong additional build- 

 ings of stone, and they are made at different places, to 

 keep the main air courses entire, in the event of an ex- 

 plosion, by means of these many lives have been 

 saved. This system may be extended almost to any 

 distance from the pit-bottoms, provided the quantity 

 of fresh air which is circulating can sufficiently dilute 

 the inflammable air which issues from the mines, and 

 keep it under the firing point. In this manner, the air 

 ventilates first one pannel of work, and then others in 

 succession, the air passing from one pannel to another 

 through the barrier or pannel walls, by means of mines, 

 as in Fig. 1. Plate CCCXCII. and may either be single, PIATE 

 double, or triple coursing, according to the quantity cccxcii. 

 of gas in the mine. 



If several coals are wrought in the same shaft, the Ventilating 

 ventilation is first completed in one coal, and from r ^ al "* 

 thence is carried by means of stapples or blind pits 

 from one coal to another, it always being the study of 

 the mining engineer to give the first of the air to the 

 working fore-heads, and that it latterly traverses the 

 old wastes. When, however, the flow of inflammable 

 air is too great, separate ventilations are made for each 

 coal. 



In ventilating the very thick coal in Staffordshire, Stafford- 

 though there is much inflammable air, less care and at- 

 tention are required than in the north of England col- 

 lieries, the workings being very roomy, and the air 

 courses of comparatively small extent. The air is con- 

 ducted down one pit, carried along the main roads, 

 and distributed into the sides of work, as represented 

 in Plate CCCXCII I. A narrow mine, named the air Fig. 1. 

 head, is carried in the upper part of the coal in the rib 

 walls along one or more of the sides. In this instance 

 it is carried all around, and the air enters at the bolt hole 

 e. Lateral openings, named spouts, are made from the 

 air- head mine into the side of work, and the circulat- 

 ing current mixed with the gas in the workings enters 

 by the spouts, as represented by the arrows, and re- 

 turns by the air head at g to the upcast pit. 



When blowers are met with in the first of the air, Blowers. 

 by which all the gas which issues from a blower is 

 carried along the wall faces where the men are working, 

 so as to render their situation very dangerous, it is 

 necessary to reverse the course of the air, in order 

 that the issue of gas from the blower shall be dilu- 

 ted by the last of the air, and carried directly to the 

 upcast shaft. This is effected by applying the general 

 principles before laid down, and by removing the stop- 

 pings in one place of the air course, placing others in a 

 counteracting direction, and causing the one current of 

 air to cross the other by an arch, as before mentioned. 

 Sometimes these operations have to be performed at 

 places at a great distance from each other. When this 

 is the case, and the engineer has, from the plan of the 

 colliery, laid down with precision the line of operation 

 to be pursued, the men are divided into parties, each 



e " 



