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C.—3

Subject. G.— On Blasting, and the Use of Explosives. 1. Give the temperature that dynamite freezes at, and state how you would thaw it. 2. Give the composition of blasting-powder, dynamite, and raekarock, and their relative strengths, taking blasting-powder at unity. 3. If a shot missed fire, what precautions would you adopt ? What material would you use for tamping ? Also, what material would you use as a tamping-bar ? Give your reasons fully. 4. What effect, if any, has water on dynamite ? and at what temperature does it explode ? 5. How would you fire, say, five holes, in which gelatine was placed, simultaneously ? and what precautions would you take so as to insure all the shots going off, supposing that the detonators in each instance were to be relied on as good ?

Second Day.—Time : 2 p.m. to 5 p.m. Subject E.— On the Ventilation of Mines. 1. What is meant by ventilation, and why is it required ? 2. Give the composition of carbonic-acid, sulphuretted-hydrogen, and carburetted-hydrogen gases, and their effect on human life, and how they are detected in mines. Also give their percentage in the air of a mine that is deleterious to the health of the workmen employed. 3. If you had to circulate 15,000 cubic feet of air in a mine per minute, and divide it in four divisions — Ist one 6ft. by 6ft., 1,500 ft. long; 2nd „ 6ft. „ sft., 1,400 ft. „ 3rd „ 6ft. „ 4ft. 6in., 1,300 ft. „ 4th „ 6ft. „ 3ft., 600 ft. „ —assume the same pressure on each airway, and give the quantity of air passing through each. 4. If it requires a pressure of 41b. per square foot to force a certain quantity of air through an airway 6ft. by 3ft., what pressure would be required to force the same quantity through an airway 4ft. 6in. by 4ft., both airways being of equal length ? 5. Describe the different mechanical appliances you are acquainted with for ventilating mines.

Thied Day.—Time : 9 a.m. to 12 noon. Subject J. — A Knowledge of the different Bocks where Gold, Silver, Tin, Copper, Zinc, Lead, and Antimony are found, and on the Formation of Lodes and Leads. 1. What metallic ores are usually associated with granite, gneiss, slate, propolyte, serpentine, and limestone respectively ? 2. What is the composition of electrum, hessite, stephanite, proustite, galena, cerussite, chalcopyrite, tetrahedrite, stannine, brookite, wolfram, calamine, siderite, pyrrhotine, mispickel, braunite, diallogite, and chromite ? Subject H.— The Effect that Faults, Slides, and Mullock Bars have on Lodes, and how to ascertain the Direction of Slides and Heavals. 1. Give six diagrams, with verbal explanations, to illustrate the effect that is exercised on mineral lodes by faults, slides, and mullock bars ; and describe instances from personal observation. 2. Describe the application of Schmidt's law for the recovery of a lost lode.

Thied Day.—Time : 2 p.m. to 5 p.m. Subject I.— A Knowledge of Underground Surveying, and the Making of Plans of Underground Workings, showing also the Dip or Inclination and Strike of the Beefs or Lodes. (a.) The candidate must produce a plan drawn to a scale not less than 5 chains to an inch, showing the surface boundaries of a mining claim not less than 20 acres in extent. The plan must also show the underground workings on the same plan, but in different-coloured inks. All traverselines on which the survey is based must be shown, with their bearings and lengths, all offsets to boundaries or other objects, together with the lines connecting the underground with the surface survey. The plan must have a north point, and the word "magnetic" or "true" written on it according to the meridian used. All traverses should be calculated from the starting-point. The plan must bear a' certificate as follows : "I certify that the survey from which this plan has been drawn was done by myself, and that the plan is my own work also " ; and it must be signed and dated. The area in acres must be shown. (b.) The original field-notes of the survey must be produced, together with the tables of meridian and perpendicular distances (if any) for each traverse station in the survey: also produce a specimen of the method of calculations from which the positions have been derived. All of these must be signed by the candidate and dated. (c.) Give a full description, in writing, of the method adopted in the survey, describing the initial point from which it was started, and show the close of the work, either in links or feet and the angular difference on closing. Describe how the inclined measurements were reduced to horizontal. State whether the true or what other meridian was used, and whether the same meridian was used both above and below ground. (d.) Say what precautions were used to ascertain if the instrument was in adjustment, and how the length of the chain or tape was tested. What instrument was used for the angular measurements, and what for the linear measurements. (c.) Draw a rough diagram to show how the surface and underground surveys were connected, and describe in writing the method adopted. State your opinion of the most accurate way of performing the above operation—first, when there is only one shaft; second, when there are two or more shafts.