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APPENDIX B. PAPERS SET AT THE 1906 MINE-MANAGERS' EXAMINATIONS. Examination op Candidates for Certificates of Competency as First-class Mining-managers. Subject No. 1. — On Shaft-sinking, Tunnelling, and Opening out a Colliery. 1. If you were charged with the exploitation of a coal lease of 2,500 acres, and the strata were monoclinal, what preparatory measures would you adopt; also, how would you determine the position of shafts and service equipments ? 2. Describe and show by sketches the various methods of sinking through heavily watered alluvial deposits. If portion of a shaft 18 ft. diameter in the clear is to be lined with cast-iron tubbing, with water-pressure thereon of 197 lb. per square inch, what thickness of metal would you have put in ? 3. What are the dangers to be apprehended from the turning and oscillation of the sinking bucket in a deep shaft ? Show by sketch a suitable apparatus to prevent such ; and how is it fixed ? 4. Describe the method of putting in a bricking curb in a sinking shaft, also of putting in a length of brickwork ; likewise the method of putting in a water-ring. What precautions should be taken during these operations {a) if inflammable gas is given off, (b) if the sinking is in hard ground ? 5. Two shafts, 1,750 ft. and 1,785 ft. deep respectively, are sunk from a level surface to a gassy seam 5 ft. thick, having inclination of 1 in 10, with a soft floor : give dimensions of shaft-pillars, and state which shaft you would make the upcast, and why. Show by sketches position of shafts and shaftpillars, arrangement of pit-bottom, position of main intake and return airways, direction of air-currents through workings to upcast. Give sizes of air-courses and roadways. Provide for a daily output of 1,300 tons. 6. Describe and show by sketches the different kinds of cage-conductoTS used in shafts, and the various methods of arranging and fixing same. Subject No. 2.— On working Coal, and timbering underground. 1. Explain the advantages and disadvantages of bord-and-pillar and longwall methods of working coal-seams, respectively. Describe and show by sketches the system of working under the foregoing methods. 2. Given a coal property of 1,200 acres, with a seam 6 ft. 3 in. thick, dipping 1 in 18, and a cover of 1,100 ft., with hard bottom and tender roof, what system of working would you adopt, and why ? Show by sketch how you would lay out the workings. 3. Explain the different causes of " creep," and give sketches showing effect of same ; also describe what precautionary measures you would adopt to obviate " creep " under the various conditions. 4. Describe, and show by sketches, how you would set props, also timber sets, for the support of the roof in a seam having an inclination of 30° ; likewise how you would secure a longwall face, with tender roof and floor, the seam being 4 ft. 9 in. thick, and inclination 1 in 5. 5. Calculate the diameter of a circular beam of timber, 12 ft. between supports, and load distributed, for a breaking-strain of 100 T % tons (coefficient of rupture, -75). 6. Describe, and show by sketches, in plan and side elevation, the different systems of working and timbering places, both in flat and very steep seams, also the method of securing the working-faces under both conditions, whilst holing and cutting. 7. Describe, and illustrate by sketches, different methods of pillar-working, and explain the principal dangers to be guarded against during extraction. Subject No. 3.— On the Gases of Mines, Spontaneous Combustion, and Ventilation. 1. Give the chemical properties of firedamp and black damp, and their weights compared with atmospheric air. State the residual gases from an explosion of firedamp, and what are their properties and effect on human life. 2. Under what conditions may a small amount of explosive gas render a mine exceedingly dangerous ? Also, if a quantity of gas occupies 19,750 cubic feet when the barometer reads 30-3 in., how and in what manner will the volume be affected if the barometer falls to 28-4 in. ? 3. It is required to travel 90,000 cubic feet of air per minute through an airway 18 ft. wide by 8 ft. high, and 1,790 yards long : what pressure will be needed to do so ? Give answer in feet of air-column, and also inches of water gauge ; likewise show what quantity of air would pass if water gauge doubled. 4. State what are the causes of spontaneous combustion in mines ; also name the gases generated by gob-fires, and describe their properties and action on human beings. In a seam liable to spontaneous combustion, what precautions would you take to obviate the occurrence of fires ? 5. Descrbe the various systems of ventilation in mines. Show sketches of an overcast and undercast, and describe their uses ; also explain the uses of regulators, doors, and stoppings. State the most advantageous method of splitting air, and its limit. 6. Forty thousand cubic feet of air per minute is split into three airways, A, B, and C : A is 1,400 yards long, 4 ft. high, and 6 ft. wide ; B 1,000 fathoms long, 5 ft. by 7 ft, ;" and C is 7,500 ft., and 6 ft, by 12 ft, : what quantity will each get ? 7. A volume of 310,000 cubic feet of air per minute is passing in a downcast shaft 18 ft, diameter and 1,300 ft. deep : what is the extent of rubbing-surface, also the velocity of air per second ?