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Subject 6. — Tapping Water in Mines; and Mode of Constructing Dams in Underground Workings, to keep the Water back. (ft.) If a large body of water was met with in a mine, and there was a suitable place where a dam could be constructed in the solid rock, show by sketches—(l) how you would construct a concrete or brickwork dam ; (2) a timber dam. (3.) State the pressure in pounds that there would be on the face of a dam containing 36 square feet if the water was standing to a height of 150 ft. (b.) If a large body of water was met with near the surface when sinking a shaft, and an impervious stratum was met with after going through the ground containing the water, show by sketch how you would dam the water back so as to prevent its going down the shaft. (c.) If you were approaching a place where there was known to be a large lodgment of water, what precautions would you adopt (1) in tapping the water? (2.) If you were approaching the water with an adit or drive in alluvial drift, how would you secure the end of the adit or drive on approaching the water ?

Time : 2 p.m. to 5 p.m. Subject 7. — On Blasting and the Use of Explosives. (ft.) What are the relative strengths of dynamite, rackarock, and blasting-gelatine as compared with blasting-powder by weight, and what are the different effects produced by these explosives ? (b.) At what temperature will dynamite become in a frozen condition, and, when in that condition, what is the effect produced as regards the strength of its explosive power? Also, when dynamite is in a frozen state, what steps would you take, and in what manner would you restore it to its normal condition ? (c.) Show by figures how you would calculate the quantity of blasting-powder requiring to be used in blasting solid rock where the borehole was 2in. in diameter, 4ft. in depth, and the line of least resistance 2ft. 6in. (d.) If, say, shots had to be fired simultaneously, how would you effect this in order that the whole might go off at the same instant ? (c.) If a shot missed fire, what steps would you take ? Also, what material and tools would you use in tamping a shot ?

Subject B.—The Effect that Faults, Slides, and Mullock Bars have on Lodes, and how to ascertain the Direction of Slides and Heavals. Describe what is meant by the terms "faults," "slides," "mullock bars," and "heaves," and give a diagram to illustrate the effect of each on a mineral lode.

Thied Day.—Time : 9 a.m. to 12 noon. Subject 9. — A Knowledge of Underground Surveying, and the Making of Plans of Underground Workings, showing the Dip or Inclination and Strike of the Beefs or Lodes. (a.) The candidate must produce a plan showing the surface-boundaries of a mining-claim less than twenty acres in extent, on a sufficiently large scale to show also (in different-coloured ink) the underground workings, with all traverse lines, figures, &c, to illustrate the method of survey adopted. Both plan and survey must be the work of the candidate. The plan must be signed and dated. (b.) The original field-notes of the survey must be produced, also the tables showing the distances of all traverse stations on meridian and perpendicular, and a specimen of the calculations from which they are derived. (o.) Describe in writing the method by which the survey has been made, name the instruments used in the measurement of angles, and of distances. Describe how the inclined measurements have been reduced to horizontal. (d.) Describe in writing the method adopted of obtaining the bearings used in the surveys, and say whether they are derived from the triangulation meridian, magnetic meridian, or other, and whether the same meridian is used both above and below ground. (c.) What precautions were taken to insure that the chain or tape was of the right length ? (/.) Draw a diagram to show how the surface and underground meridians have been connected, and describe fully how it was done. (a.) State your opinion as to which is the most accurate method of carrying the surface meridian to the underground survey, in the case of a shaft or shafts. (h.) Does the compass give reliable results in underground surveys? State your reasons. (i.) In an underground survey, how would you check a magnetic survey, and compare the meridian used with the surface survey and boundaries of the claim ?

Time : 2 p.m. to 5 p.m. (/'.) From the first traverse station used in the underground survey, calculate the distance due north'to the nearest boundary of the claim, and show your manner of calculating it. (k.) Describe in writing the adjustments of a plane theodolite, and also those of a miner's dial or compass. (The candidate will also be examined orally in the use and adjustments of these instruments.) (I.) Describe how the traverses, boundaries, offsets, or other features were plotted on the plan, (m.) Describe the method of calculating the areas of irregular figures on the plan,