PROCEEDINGS OE GEOLOGICAL SOCIETIES. 



73 



area that would only admit of a very limited output if the long-wall sy stem 

 was used. With many this is an advantage that must weigh much in its 

 favour ; although he was not an advocate for raising very large quantities 

 where a smaller quantity, with judicious management, would produce a 

 better profit. With the pillar-and-stall system the workings may be con- 

 ducted any reasonable distance upon the line of level, the only limits being 

 the increased cost of conveying the coal to the pit's eye, and the difficulty 

 of thoroughly ventilating the workings, owing to the increased drag or 

 resistance that has to be met in conveying currents of air through long 

 air-courses. 



With the long-wall system the case is very different ; for owing to the 

 difficulty and expense of keeping good the wagon- and air-roads, the dis- 

 tance is practically limited in many mines to a few hundred yards. The 

 greatest distance on the line of level known to be worked out upon the 

 long-wall system is rather more than 800 yards. 



Where there are numerous faults, it is difficult to work a mine to advan- 

 tage upon the pillar-and-stall system, but it is still more difficult upon the 

 long-wall system ; but the former system can be used under some circum- 

 stances where it would almost be impossible to work upon the long-wall 

 system. 



The quantity of timber that is used is not materially different whether 

 the coal be worked on the long-wall, or pillar-and-stall systems, providing 

 equal skill is displayed in laying out the workings, etc. While the cost of 

 getting depends so much upon circumstances that it is unsafe to hazard an 

 opinion in favour of either system, unless both have been employed in the 

 same mine, under very similar circumstances, — and even in cases where 

 that course has been adopted — the results have been sometimes in favour 

 of the pillar-and-stall system, and at others vice versa. It may be that 

 occasion all}'' some other system will answer better than either of the sys- 

 tems under consideration, for we by no means embrace the whole of the 

 systems of getting coal when we speak of the pillar-and-stall and long- 

 wall, although mauj'' of the methods of working coal are but modifications 

 of either one or the other. 



Mr. Binney said : " No doubt there will be more advocates for the pillar- 

 and-stall system in Lancashire than for the long-wall. If the Lancashire 

 gentlemen went into North Derbyshire, probably they would find a great 

 many advocates of the long-wall system, and they would see advantages 

 there which they do not see in Lancashire. The same remark will apply 

 to the East of Scotland. The different systems of long-wall and pillar- 

 and-stall workings would have different advantages in particular districts. 

 In Derbyshire, where the long-wall system has been going on for 150 

 or 200 years, the men are so thoroughly drilled to it, and work it so scien- 

 tifically, that its results would hardly be fair as applied to Lancashire, where 

 it would take a long time to get men to work so well at it as they do in 

 Derbyshire. On the other hand, there would be a like difficulty in intro- 

 ducing the pillar-and-stall system into Derbyshire. 



Philosophical Society, Mastchestee. — January 13. — Mr. E. W. 

 Binney, the President, said: — In a very valuable work lately published by 

 that eminent geologist Dr. Geinitz, of Dresden, entitled* Dyas, or the 

 Magnesian Limestone Formation and the Lower New Red Sandstone/ the 

 author, whom he had the pleasure of accompanying over some of the Per- 

 mian deposits of South Lancashire, hail clone him the honour to allude to 

 two papers of his, ' On the Permian Deposits of the iS T orth-west of Eng- 

 land,' printed in vols. xii. and xiv., second series, of the Society's Me- 

 moirs. 



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