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Subject 2. — The various Methods adopted in timbering Shafts and Mines, and in filling in Old Workings. (a.) Show by sketch how you would timber a rectangular shaft—(l) with frames; (2) with planks, say, 4in. thick; and show how you would fit the planking at the corners if battens were not used, and to retain the whole strength of the planks. (b.) Show by sketch how you would place a tank in a shaft, at the change of pump-lifts. (1.) If the shaft was not large enough, show how you would enlarge it at the change of lifts in order to leave room to place the pumps in position. (c.) What precautions would you adopt to keep the sets of timber in an adit-level in position if the ground was bad and the timber liable to cant ? Also, if both the roof and floor were soft ground containing water, describe fully how you would secure it with timber. (d.) What dimensions of a cap-piece would you use in heavy ground if the drive were sft. in the clear between the timber, and the sets 4ft. apart from centre to centre ? (1.) Assuming that each cap-piece had to carry a uniform load of 5 tons, what would be the diameter of a round cap of red-pine sufficient to carry this load, and have 4 of a factor of safety (that is, its breaking-strain would be 20 tons) ? (2.) Give the diameter of a round prop of 6ft. in length of red-pine capable of carrying 6 tons, and to have 4of a factor of safety. Show by calculation how you arrive at this. (c.) In timbering a roadway constructed on an. inclination of 1 in 4, show by sketch how you would place the sets in relation to the inclination. (/.) If you were stoping out a quartz-lode, say, 60ft. in width, and the ground heavy, describe fully how you would work a lode of this description, and how you would timber the stopes.

Time : 2 p.m. to 5 p.m. Subject 3.—On the Drainage of Mines, and on Pumping Appliances. (a.) How many different kinds of pumps and appliances are used for draining mines? (6.) From what depth will a pump draw water ? Is there any limit ? If so, why ? (c.) Describe a steam-pump having a reciprocating motion, and where it should be placed for its efficient working. (d.) Describe a pulsometer pump. On what principle does it work, and where should it be placed ? (c.) How many tons of water will be raised from a shaft in twenty-four hours—diameter of pump, 22in.; 6ft. stroke ; making twenty strokes per minute ; single-acting ; efficiency of pump, 75 per cent. ? (/.) What thickness of metal would be required for cast-iron pipes 12in. diameter, head of water 900 ft. ? Give thickness of top and bottom lengths. (g.) What would be the weight of pipes in the above question ? (h.) What class of pump gives out the highest efficiency?

Subject 4. — The Haulage on Planes and in Shafts, also the Different Systems of Underground Haulage, with Horse-power required to do the Work. (a.) Describe the different methods adopted for underground haulage. (b.) Describe a safety-catch. On what part of a cage is it attached, and for what purpose? (c.) What appliances are used to indicate the position of a truck on a plane, or a cage in a shaft, and where are they situated ? (d.) A 3in. steel-wire rope—what is its safe working-load ? (c.) A 3in. steel-wire rope —what is its breaking-strain ? (/.) What is meant by the term " horse-power " ? (g.) How many heads of water would be required to raise 100 tons of stone 450 ft. in twentyfour hours—diameter of overshot wheel, 30ft.; efficiency of wheel, 65 per cent, (weight of cage, truck, and rope omitted) ? (h.) What " horse-power " would be required to raise 200 tons of stone 500 ft. in twelve hours —weight of cage 30cwt., rope 15cwt., and truck 20cwt.; truck to contain 4 tons ?

Second Day.—Time : 9 a.m. to 12 noon. Subject 5. — On Ventilation of Mines. (ft.) How is natural ventilation produced ? Also, state how you would ascertain the quantity of air travelling through an airway. (b.) If 15,000 cubic feet of air per minute were travelling through an air-course 6ft. by 4ft., and 1,200 ft. long, and if this air was divided into two air-courses, and to have the same pressure as in the main air-course, what quantity would pass through each of the following divisional aircourses?—lst division, sft. by 3ft., I,Booft. long; 2nd division, 4ft. by 3ft., 2,500 ft. long. (c.) Give the composition of carbonic-acid gas, also carburetted hydrogen gas, and state what means you would adopt to detect their presence in amine. - ' (d.) What effect does water produce on carbonic-acid gas, and in what part of the workings in a mine where carbonic-acid gas is generated would you expect to find the largest quantity ? Explain fully your reason why. (c.) What is meant by mechanical ventilation ? Describe the systems in use. (/.) If an ordinary fan, 3ft. in diameter, with a width of Ift., and making 1,200 revolutions per minute, were used for ventilating a mine, what quantity of air would it put in circulation ?

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