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4. In what system of working coal are chocks used in preference to prop-wood ? What are the advantages of using timber in this form ? 5. What fittings are required for relieving the cast-iron tubbing used in shafts from the pressure of water during time the tubbing is being fixed in position ?

First Day.—Time : 2 p.m. to 5 p.m. Subject lll.— The Various Methods of heiving and cutting Coal of Different Classes to advantage, and securing Ground while so engaged. 1. Describe the mode of working any seam of coal with which you are acquainted, and show by sketches the position of main level and branch headings. 2. What size pillars would you leave to support shaft 200 yards deep, seam pitching at an angle of 14 degrees ? 3. The greater number of accidents are due to falls of roof and sides in working-places. State wnat, in your opinion, is productive of such accidents, and how they may be prevented. 4. What does the Coal-mines Act require as to the inspection of mines before starting work ? 5. What precautions should you take with regard to missed shots ? Subject IV. — The Various Methods of Ventilation, and the Construction of Airways so as to produce a Good Circulation of Fresh Air in any Part of a Mine. 1. What size would you make an airway to pass 10,000 cubic feet of air per minute, at a velocity of 4 ft. per second ? 2. State your views as to how a mine is affected during a heavy fall of the barometer ? 3. What are the most dangerous gases commonly met with in coal-mines ? Why are they dangerous ? And state which of these you have had most experience of. 4. What is the duty of a manager as regards ventilation, and what is the minimum quantity of air which should circulate per man employed in non-fiery mines ?

Second Day.—Time : 9 a.m. to 12 nooni Subject V.— On the Area of Airways, the Velocity and Division of Currents, and the Deductions to be made for Friction. 1. State the general laws relating to the friction of air in mines. 2. What quantity of air per minute will pass through a shaft or circular airway 10 ft. diameter, speed of current being 5 ft. per second ? 3. Explain use of water-gauge, and state when it should be fixed to ascertain the drag of the mine. 4. Sketch air-crossing or bridge for carrying main return over the intake airway : say how you would construct such, and material to be employed. 5. Have you any knowledge of the construction of " ventilating-fans " ? Describe such a fan as you may have had experience of. Subject Vl.— On the Nature and Composition of Explosives and Dangerous Gases occurring in Coal-mines, and on Spontaneous Combustion. 1. Describe the best type of safety-lamp of which you have had experience. 2. Have you any knowledge of high explosives in use in coal-mines? Describe such, and give composition. 3. In what position would you expect to find black-damp or carbonic acid in a coal-mine, and what are the causes tending to the production of this gas? 4. Have you had experience of underground fires ? If so, describe what, in your opinion, led up to the firing; and state generally your views as to spontaneous combustion, and best means of dealing with a mine so circumstanced.

Second Day.—Time : 2 p.m. to 5 p.m. Subject VII.— On the Drainage of Mines, and Pumping Appliances. 1. What are the conditions which would decide you to wind the water from a shaft, in preference to pumping ? 2. What are the conditions rendering the fixing of a direct-acting pump at shaft-bottom preferable to putting a pumping-engine at surface ? 3. A shaft 100 fathoms, from which it is required to pump 100 gallons per minute, the engine being placed on surface : how many lifts would you apply ? and sketch arrangement where lifts junction. 4. Give your experience of the erectionand working of pumping appliances. Subject VIII.— The Haulage on Planes and in Shafts; also Different Systems of Underground Haulage, with Horse-power required to do the Work ; also on Strength of Hauling-rope and -chains. 1. What do you consider the most easily applied and generally useful application of ropehaulage ? Give your experience, and describe fully means of attaching the tubs to rope, also arrangement of tension.