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Second Day.—Time : 9 a.m. to 12 noon. Subject lII.— On the Gases of Mines, Spontaneous Combustion, and Ventilation. 1. What do you understand is meant by the term " noxious gases " ? Describe. 2. Name the several gases met with in coal-mines, and state fully the precautions you would adopt to render them harmless to life. 3. What are the special and general duties of a fireman at a coal-mine ? 4. In measuring velocity of air by anemometer, would you be satisfied with a measurement at one point ? If not, why so ? 5. A fan passes 5,000 cubic feet of air per minute with a water-gauge of 1-25 in.: find horse-power so represented. 6. If 20,000 cubic feet of air per minute passes along an airway of 40 ft. area which has a total rubbing-surface of 40,000 square feet, what water-gauge would you expect? 7. What is the meaning of the term "motive column " as applied to ventilation ? 8. How much has the ventilating-pressure to be increased to double the quantity of air? 9. How would you lay off the workings for a seam of coal known to be liable to spontaneous combustion ?

Second Day.—Time : 2 p.m. to 5 p.m. Subject IV. — On dealing ivith Old Workings and other Sources of Danger. 1. What precautions are necessary to be observed in driving headings toward old workings? 2. What are man-holes, and when are they usually made? 3. What precautions must be taken with regard to explosives in coal-mines ? 4. Describe briefly the operation of blasting in a coal-mine when ordinary blasting-powder in use, and danger to be anticipated from blown-out shot. 5. Give your experience, if any, in use of electricity in connection with blasting operations, and state when, in your opinion, it should be used in preference to the ordinary system of blasting by fuse. 6. Why is coal-dust to be regarded as explosive under certain conditions ? State what the conditions are. 7. What methods are in use or have been proposed for breaking down coal without use of gunpowder ? v

Third Day.—Time : 9 a.m. to 12 noon. Subject V. — On Steam Boilers and Engines used about Mines. . 1. Describe and give sketch of what you consider a good class of steam-boiler for colliery use ; show position of fittings, and the uses for which they are applied. 2. Describe the class of winding-engine you would apply to raise, say, 500 tons daily from a depth of 200 yards, giving size of rope and drum. 3. Describe class of engine customary for driving a fan, and assume one such, 18 in. cylinder (fix own length of stroke) ; speed of piston, 200 ft. per minute ; initial steam-pressure, 100 lb. per square inch; cut off at -f stroke : required, average steam-pressure and horse-power. 4. What would be the advantage of electrical transmission of power in mining operations, and what special drawbacks prevent its general use ? 5. What is meant by a factor of safety, and what factor would you allow for colliery windingropes ? 6. Describe the special precautions you would adopt in connection with coal-mining plant in order to prevent accidents arising from its use. 7. Describe arrangements for banking at top and bottom of a winding-shaft when it is desired to occupy as short a time as possible for each banking and winding.

Third Day.—Time : 2 p.m. to 5 p.m. Subject VI. — On Mine Drainage and Haulage, and Appliances for Same. 1. Describe the class of pump you would apply in sinking a shaft, say, 100 yards deep; quantity of water, 250 gallons per minute. 2. Describe a pump suitable for the drainage of dip-workings (quantity of water, 200 gallons per minute, passed through a line of pipes 1,500 ft. long to a vertical height of 300 ft.), and state what power you would adopt to work the pump, and the horse-power required. 3. Give sketch, with figured dimensions, and name the working-parts, of— (a.) 15-in.-diameter bucket lift. (&.) 15-in.-diameter plunger lift. 4. Describe usual methods of transmitting power in haulage arrangements, and name system you have experience of. 5. Describe fully the method of conveying coal by endless rope, and show by sketch means of keeping tension on rope, and means of securing tubs thereto. 6. Assume 50 tons hourly to be conveyed at the rate of 2 miles an hour by endless rope over a distance of 2,000 yards, the average grade being 1 in 10 against the load ; each tub weighs 5 cwt., and load 10 cwt. ; allowing J§- for friction of tubs, and 50 per cent, for general resistance of machinery ; the rope weighs 8,500 lb.: find horse-power required.