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Transactions . 0 In. 0 79 Fs 99 Ft. 71 13 4 4 003 306 3 84000 COAL ... BandCOAL, bot-tom ... 0 Strong splint 0 Ft. 50 1 9 I- Black stone 14 4 100 0 6 Total 127_4_3J Note.âThe George and Lady Isabella Pits are about 45 yards apart, and there is a dipdyke to the East of 7 fathoms between the two shafts. The experiment was made in the Low Main Seam at a point about319 yards south-east from the shaft, and fully 60 yards from any wholeworkings or goaf; the dip of the strata being towards the east. The roof is composed of grey metal and post girdle, is rather tender,and the thill is
Transactions . 0 In. 0 79 Fs 99 Ft. 71 13 4 4 003 306 3 84000 COAL ... BandCOAL, bot-tom ... 0 Strong splint 0 Ft. 50 1 9 I- Black stone 14 4 100 0 6 Total 127_4_3J Note.âThe George and Lady Isabella Pits are about 45 yards apart, and there is a dipdyke to the East of 7 fathoms between the two shafts. The experiment was made in the Low Main Seam at a point about319 yards south-east from the shaft, and fully 60 yards from any wholeworkings or goaf; the dip of the strata being towards the east. The roof is composed of grey metal and post girdle, is rather tender,and the thill is of strong seggar clay. The coal is clear, hard, bituminous, and moderately bright, with thecleavage well defined, and is used for household purposes. The Main Coal Seam 114 feet above is partially worked, and theHutton Seam 78 feet below is partially worked. The specific gravity is 1*24. On August 28th, 1879, a hole was bored in the solid coal at the faceof a narrow board. See Section No. 1. Section No. ICC EXPERIMENTS SHOWING Til 10 PRESSURE OF CONDITIONS. The length of the borehole was ... The diameter of â The diameter of pipe fixed in the hole Gas space ... Hole at right angles to the cleat. Coverâdepth of hole from surface Distance of hole from shaft Description of gauge used Ft In. ... 7 0 JL 2 ... 2 6 750 The hole was plugged up in the following way:âThe pipe for conveyingthe gas from the gas space to the pressure gauge was screwed at its insideend and provided with a nut and washer, the other end was providedwith a collar. Between this collar and the nut were placed, first a metalsocket, and then a number of India-rubber washers which were a littlesmaller in diameter than the hole. When these were placed in the hole theywere all screwed tightly up together, and the space round the socket atthe outer end of the borehole filled with good Portland cement. Pressureof Gas. RESULTS.âSee Table, Page 225. In the first 5 minutes after the hole
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Keywords: ., bookcentury1800, booksubjectmechan, booksubjectmineralindustries