Explosive gas in mines in the southern part of the Illinois coal field-Contd. Pressure of gas in coal beds... Method of making test.. Page. 213 213 ERRATA. Page 14, 2d line from top. After the word "combustion" insert "Some physiologists say that large amounts of CO2 have toxic effects other than suffocation." 8th line from top. After the words "coal dust" insert "It may be found that CO never occurs naturally in coal but is a secondary product." 18th line from bottom. After the word " After the word "gas" insert "The nitro gen is nearly, if not all, from the air in the mine." 12th line from bottom. Add "Air containing even considerably more than 7 per cent of oxygen might not support life, but the limit depends on many conditions." 6th line from bottom. For "10 to 30 per cent" read "5 to 30 per cent." Page 20, 18th line from bottom. For "discharged a volume estimated at 47,000 feet" read "discharged for a short time a volume estimated at 47,000 feet." Page 59, first table. Volumes of methane are cubic feet per minute, not cubic meters per minute. Page 77, 10th line from top. Add "The term 'gaseous' in a strictly classificatory sense is now often applied to any mine containing sufficient gas to cause an accident under ordinary conditions." Page 87. The barograph record in figure 11 is not reversed as stated. Page 103, 13th and 14th lines from top. For "error of at least 1 per cent" read "error much greater than 1 per cent." 8th line from bottom. For "0.10 per cent" read "10 per cent.' 6th line from bottom. For "0.10 per cent" read "10 per cent." Page 105, 2d line above table. For "31,000 cubic feet of methane a minute, or 5,760,000 cubic feet a day, weighing 130 tons" read "31,000 cubic feet of methane a minute or 43,640,000 cubic feet a day, weighing nearly 1,000 tons." 93749°-15 conditions... 3. Diagram showing rate of escape and volume of methane from 8 40 43 Explosive gas in mines in the southern part of the Illinois coal fields-Contd. Occurrence of gas in southern Illinois mines-Continued. Mines No. 7 and No. 8 of the Big Muddy Coal & Iron Co.. 204 Explosive gas in mines in the southern part of the Illinois coal field-Contd. Occurrence of gas in southern Illinois mines-Continued. Page. Publications on coal-mine accidents and methods of coal mining. 233 238 ILLUSTRATIONS. Page. PLATE I. Cross section of the northern anthracite coal basin.. II. Structural map of the northern anthracite coal basin, showing some 106 106 III. Map of part of workings in Abbott bed, South Wilkes-Barre mine, Pa.. 124 126 128 VI. Map of workings in Pittston bed, No. 14 mine, Pa.. 138 VII. Map of part of southern Illinois coal field, showing some features of the occurrence of methane.... 178 FIGURE 1. Section showing conditions at place where outburst occurred in the 25 2. Diagram showing rate of escape of methane from coal under various 40 3. Diagram showing rate of escape and volume of methane from 8 43 Page. FIGURE 4. Gas pressure in holes of various depths in English mines.. 63 5. Plan and sections showing location of holes for gas-pressure tests at 6. Diagram of pressures in test holes at Belle-Vue mine.... 11. Curves showing variations in percentage of methane and barometric 87 12. Curves showing relation between length of flame of a blower and 13. Curves showing variations in volumes of methane and carbon diox- 14. Curves showing variations in percentage of methane and barometric 15. Ideal section through coal workings showing area in which flow of 16. Curves showing variations in atmospheric pressure, percentage of 17. Curves showing variations in atmospheric pressure, percentage of 18. Columnar sections showing stratigraphic position of coal beds in 106 19. Columnar section of coal measures at Lance mine, Plymouth, Pa... 108 109 111 112 113 114 115 117 121 130 currents sampled in November, 1910... 135 30. Map of workings in Dunmore bed, Sloan mine.. 140 31. Section through Auchincloss mine near Nanticoke, Pa., showing 158 32. Tube inserted in coal to ascertain pressure and flow of gas. 214 33. Relation between depth of mines and amount of methane per ton 223 |