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2. Describe fully (a) water-blasts, (b) furnaces, and (c) fans. Illustrate each, and state under what conditions you would use them for mine-ventilation. 3. What is natural ventilation ? Would you rely on it in a mine liable to give off noxious gas ? Give reasons fully. 4. A fan circulates a current of air having a velocity of 23J ft. per second through an airway measuring 7 ft. 9 in. by 6 ft. 4 in. The water-gauge shows a depression of 1-75 in. Assuming the fan to give a useful effect of 54 per cent., what I.H.P. must the engine develop, allowing 15 per cent, of its power to be absorbed by friction ? 5. If you had a current of air of 16,000 cubic feet per minute which became fouled by a blower giving off C0 2 at the rate of 200 cubic feet per minute, how much more air would be required to dilute this gas so as to make it harmless, and to what extent would the ventilating-power have to be increased, the airways remaining unaltered ? 6. Assume a mine, in which much timber is used, having three working levels, and the timbers of the middle level get on fire. It being impossible to extinguish with water, what action would you take to put out the fire, and what precautions would be necessary for the safety of the men engaged in the work ? Subject D.— Tapping Water in Mines, and the Mode of constructing Dams in Underground Workings to keep the Water back. 1. In opening a new mine the water of an abandoned mine, 300 ft. in depth and flooded to the surface, has to be dealt with. What method would you adopt to cope with this water so as not to stop the work of developing the mine, and what precautions would you take to insure safety ? 2. In sinking a shaft a heavy feeder of water is met with 200 ft. from surface. Show how you would deal with this feeder so as so insure safety and also economy in the future working of the mine. 3. A dam has to be built in a roadway 6 ft. 4 in. high by 4 ft. 10 in. wide. Head of water, 220 ft. Show how you would construct a suitable dam, and give total pressure on same. 4. If when driving a crosscut you come upon a borehole 400 ft. deep and carrying a considerable flow of water, how would you keep back the water, assuming that 20 ft. of strata immediately overhead was weak and somewhat soft? Subject E.— Blasting and the Use of Explosives. 1. What are the various explosives used in mines? Give composition and characteristics of each; also relative powers as compared with ordinary blasting-powder. Enumerate the conditions under which each explosive may be used to the best advantage. 2. What precautions are necessary to observe for the safe storage of the different classes of high explosives ? 3. How would you prepare a frozen nitro-glycerine compound for safe and efficient use ? 4. What material would you use for tamping the various explosives used in mines; and, assuming dynamite being used in a place where the air-current is inadequate to carry off the fumes,' how would you make the place fit for working in after a shot has been fired ? 5. Describe the various methods adopted for shot-firing. State the precautions to be taken before firing, and also in the event of a miss-fire. Subject F.— A Knowledge of Arithmetic and the Method of keeping Mining Accounts. 1. A block of quartz measures 20 chains in length ; at one end it is 250 ft. high and 7 ft. 6 in. wide, at the other end it is 127 ft. high and 5 ft. wide. Assuming the tapering in height and thickness to be regular, how many cubic yards are contained in the block ? 2. What is the value of four pieces of timber, each 24 ft. 6 in. by Ift. 2 in. by 10 in., at 12s. 6d. per 100 ft. superficial ? 3. An ore assays 17dwt. of gold per ton; battery extraction, 71 per cent.; value of gold, £3 17s. 6d. per ounce. What are the values of gold saved and lost after the treatment of 720 tons ? 4. Show in detail the method of keeping wages and general working accounts; also of taking out the costs per ton per month of the various departments of mining and battery work, the amalgamation process only being adopted at battery. Oral. Subject G.— A Knowledge of Part V. of " The Mining Act, 1898." Subject H.— Pumping Appliances and the Drainage of Mines. 1. What is a siphon, and to what extent and under what conditions can it be advantageously used in mines ? 2. Assume two pumps worked off one beam, one pump at each end. The beam is 20 ft. long between pump-centres, and balanced 12 ft. from the centre of a 16 in. pump having a stroke of 6 ft. What size of a pump is required at the other end of the beam to give a working balance ? 3. A double-acting duplex pump has 4 in. plungers and a piston-speed of 85 ft. per minute. What quantity of water will it pump per hour, allowing 8 per cent, for slip ? 4. Describe and illustrate bucket and ram pumps, and show under what conditions both may be worked together. Show connection with engine.