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(a.) What form of shaft do you prefer, and why? Give the dimensions of a shaft suitable for raising 500 tons a day from a depth of 600 ft.. allowing for pumps. (&.)-.What is tubbing ? Describe the process of fixing and finishing it. (c.) How do you secure pumps in a shaft lined with tubbing ? (d/) Draw a sketch of a sinking-bucket, showing attachment to rope. (c.) Give a plan and section of a long wall stall, showing timbering. (/.) What is meant by dividing a mine into districts ? What is to be gained by this proceeding ? Subject 2. —The various methods adopted in securing shafts and workings in a mine, showing the relative advantage and efficiency of each class of material used: — (a.) What materials are used for securing shafts ? Under what circumstances should each be employed ? (b.) Give sketches of timbering workings—(l) for a steep seam, and (2) for a hard roof and soft floor. (c.) What is the best form of timbering to resist a creep? (d.) Give a sketch indicating how sprags should be set. Subject 3. —The various methods of ventilation, and the construction of airways so as to produce a good circulation of fresh air in any part of the mine : — (a.) Describe fully what is known as natural ventilation. Is this always to be relied on ? and, if not, give the reason. (b.) What system of ventilation should you adopt—(l) in a fiery mine, 450 ft. deep; (2) in a non-fiery mine, 2,000 ft. deep ? (c.) Which is more easy to ventilate—(l) a rise heading, or (2) a dip heading ? Explain fully. (d.) What is a " dumb drift " ? Explain its use, and state any objections to it. (c.) What precautions are necessary, in erecting a fan, to guard against damage from any catastrophe in the pit ? (/.) Describe the various methods by which the air-current is measured. (g.) How much pressure per square foot does 3in. of water-gauge represent ? (h.) Draw a sketch of a district in a fiery mine where the bords are 18ft. wide and the pillars 48ft. thick, showing direction of air-current. (i.) Describe and draw—(l) overcast, (2) ventilating-door, and (3) regulator. What are they used for ? (j.) If you have an old working, 30ft. high, approached on each side by a road 10ft. in height, and a small blower of gas exists in the top of the large excavation, what steps would you take to prevent an accumulation of gas ? (2 p.m. to 5 p.m.) Subject 4. —On the areas of air-ways, the velocity and divisions of air-currents, and the deductions to be made for friction :— (a.) At what velocity should air traverse the workings of a mine ? (b.) What is the cause of friction of air in mines ? (c.) In an airway measuring 9ft. by 17ft. the air travels 72ft. in nine seconds : what is the quantity passing ? (d.) What do yoit understand by splitting the air ? What is the advantage of this proceeding ? (c.) What is the rubbing-surface of an airway measuring Bft. Gin. by 9ft. 2in., and 1,150 ft. in length ? (/.) If we require to treble the quantity of air in the same airways, how much must we increase the power ? (g.) What is the objection to small airways ? (7t.) Eind the weight of a cubic foot of air at 30in. barometric pressure and 61° Fahrenheit. (;'.) Which is preferable, an airway measuring 4ft. by 12ft. or one measuring Bft. by 6ft. ? Give your reasons. Subject s. —On the nature and composition of explosive and dangerous gases occurring in coal" mines, and on spontaneous combustion : — (a.) What dangerous gases are met with in coal-mines ? Give them in the order of their specific gravities (the lightest first), and state their compositions and characteristics. (b.) At what point does a mixture of firedamp and air become most explosive, and how much air is required to dilute it to such a point that it will not explode at a naked light ? (c.) What means have we of discovering the presence of light carburetted hydrogen ? (d.) What is choke-damp ? In what portions of the workings is it most likely to be found? (c.) What effect has the addition of carbonic-acid gas on an explosive mixture of air and firedamp ? (/.) What is a "gob-fire" or "goaf-fire " ? Give theories as to its origin. What means are usually taken to prevent these fires ? (g.) What are the preliminary symptoms of a gob-fire ? (h.) Eecently a man descended a coal-mining shaft in which there had been for some time no ventilation, and fell back against the side, overpowered by gas. Close to the mouth of the shaft was a water-wheel driven by a. race, but not available for winding. There was only one man at the top of the shaft. What ought he to have done? (i.) Under what circumstances, if any, will a mixture of ninety-eight parts of air and two of firedamp explode ? Second Day (9 a.m. to 12 noon). Subject 6. —On the drainage of mines, and puinping-appliances :— (a.) Show by sketch the method of fixing supports in shafts for pumps and rising mains.

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