1898 - Coalmininghistorypa.org

No. 11. BUREAU OF MINES. xvparallel to it, as iu a face pillar, which, of course, is subject to theside hill thrust dowu grade ou its weakest side.Fourth. Ill the loug run the butt work is in favor of the miiier(^though hard ou him iu its first stage), because in cutting over todraw the pillars the work is all face work, which is much easier.For instance, our butt rooms are laid out on -40 foot centres, withThe face rooms are on the samea 10 foot room and a 30 foot pillar.centres, but with a 12 foot face and a 28 foot pillar.In drawing out the pillar the miner has to cut over about every"2')foot length of pillar drawn back, so it is quite a relief for himto be able to do that work on the face.In the face room, when the miner conies to draw the pillars,the cutting over them has to be done on the butts.In short, the actual butt work, in the butt rooms, is 10 feet indriving up the room, and face work in drawing out the pillar, 30feet, or 3 to 1 in favor of the miner. The face work would be 12feet in the face rooms and 28 feet butt work drawing pillar, or 3 to7 against the miner.Fifth. The pillar in the butt room is taken out without the useof turns, which are expensive, and necessary in face work whencoal is mined ou grades.Sixth. There is less waste of coal by the butt room system thanin face rooms on a grade, as the bottom coal is not left on the dipside to keep roads level, which is no insignificant loss on heavygrades.We are not the introducers of the butt room system, as it is inpractice at several other mines, and we do not know who werethe originators (there seem to be many aspirants for that honor), but"whoever oinginated deserves much credit.In conclusion, I wish to remark that we were of necessity compelledto mine considerable coal between the shafts and the presentdevelopments.The ventilation as shown by plan is not the final system, as thev,ork is still incomplete, but will be indicative of the intended system.Yours very truly,FRED. E. KEIGHLEY,Superintendent.Mr. Keighley says further that he will be greatly disappointed ifhe does not get fully ten per cent, more coal per acre than is securedby the best work on the advancing system. The advancingsystem is wrong in principle, yet an extraordinary good roof, lightcover and easy grades would enable a careful man to make a showingthat would be very hard to excel by any other method. For years,the mines of the Connellsville Coke Region were worked on the advancingsystem, and up to ten 3'ears ago fully 50 per cent, of the areaall