C—4.

8. In Bin. pipes, 330 ft. deep, show by calculation what thickness of metal you would use, and how would you specify that they should be cast ?

VIII. — The Theoretical and Effective Power of Steam-engines and Boilers ; also, on the Strength of Hauling-ropes and Chains. 1. You have to wind 1,000 tons a day of 10 hours from a depth of 260 fathoms, what form of engine would you use ? Give size of cylinders, stroke, and steam-pressure, the details of boilers, and what would be the nominal horse-power. Give the data which you assume for weights of ropes, cages, boxes, &c. . 2. With a compound engine, 12in. and 24in. cylinders, what tonnage of coal would you wind from 240 ft., with a steam-pressure of 551b., and cut off at f the stroke? 3. Winding 450 tons daily, 10 hours, from 32 fathoms, what size of cylinders, and stroke, and what pressure of steam would you employ for a single engine ? Give size and kind of rope you would use. 4. What are the relative advantages of flat and round steel ropes ? Had the flat hemp ropes anything to recommend them? What were their disadvantages? 5. What is a safe load for a fin. chain ? What factor of safety do you employ? 6. What is a safe load for a steel-wire rope (1) llin. diameter, (2) lfin. diameter? 7. How many gallons a minute will an engine of 120-horse power pump from a depth of 70 fathoms.

Fiest-ceass Ceetipicates.—Thied Day.—Time : 9 a.m. to 12 noon. IX. — The Incrustations in Steam-boilers, and the Cause of same, and Bemedy therefor. . 1. Name the principal substances which form incrustations in boilers. How is this caused ? Name the various means you would adopt for preventing this. Give your opinion of the principal cause of boiler-explosions. 2. What class of boiler would you use for a winding-engine of 120-horse power. Give your reasons. Also (1) give the area of heating-surface, (2) surface-area of fire-bars.

X. — Tapping Water in Mines and the mode of Constructing Dams in Underground Workings to keep Water back. 1. How would you approach a large body of water with a head of 200ft.—(1) from the dip, (2) from the rise ? What sized rib of coal would you leave in above cases—(l) in a hard coal (2) in a soft coal ? Would the thickness of the seam affect the question ? Assume that roof and pavement are sound. 2. What distance will water under pressure run in the solid coal ? Give your opinion if it is a freely-jointed seam. 3. How would you construct a dam in a seam impervious to water with sound roof and floor? 4. Would you put in dams in roadway leading to workings where you would have a heavy head of water if the coal were soft and pervious ?

XL — Blasting and the Use of Explosives. 1. What explosive would you use (1) in driving a mine in hard quartz grit, (2) in working coa in a fiery mine, (3) and in which firedamp was occasionally met with; and what precautions would you adopt ? 2. What is the composition of dynamite fumes ? State your arrangements where dynamite would be largely used. 3. What is the composition of rackarock and gun-cotton ? 1. Compare blasting-gelatine and dynamite. 5. What is a blown-out shot ? Can it be prevented ?

Time : 2 p.m. to 5 p.m. Xll. — The effect that Faults Produce in Goal-seams, and how to ascertain the Direction of a Coal-seam ivhen severed by a Fault. 1. What is a reversed fault and its cause? Are there any such in your district? if so, describe. 2. How do you measure the amount of throw in a fault in an inclined seam ? 3. What is meant by a fault ? Give the general rule for finding the coal. 4. Is there any reason for a fault altering the character of a coal-seam? if so, explain. 5. Do faults cause any further inconvenience to a mine than the dislocation and driving they entail.

XIII. — A Knowledge of the Composition and Character of the Different Classes of Goal, and also of the Character of the Bocks and Formation of the Country where Coal is likely to be • found. 1. What is an anhydrous coal ? Is there any true coal found in New Zealand ? if so, where ? 2. Give the proximate composition of (1) a good pitch or brown coal, (2) of an English coal. 3. What two bodies are chiefly detrimental to the quality of lignite ? 4. How do you account for the dull look of lignite or brown coal and the glossy lustre of pitch coal, in view of them both occurring in the same field.

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