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under the bed of a river, such as the Yarra, to junction with a portion of the work carried through from the other bank, but flooded out and incomplete.

The lining of the tunnel is within 4 feet of the river bed for a distance of 60 feet, and the ground is chiefly silt and drift sand, the mean density of the material being about 120 lbs. per cubic foot. A hard band of conglomerate from 6 inches to 12 inches thick is met with about half way up the section of the tunnel.

Describe carefully, with sketches, how you would proceed to carry out the job without the use of an air-lock. Give drawings of the shield you would use, shewing carefully all provision for keeping water out of the workings; also shew how you would deal with the hard band, what precautions you would take to prevent settlement either of the shield or of the finished work, and how you would effect the junction with the existing portion of the work.

MINING.

FIRST PAPER.

Mr. F. M. Krausé, F. G. S., F.L.S.

GEOTECTONIC AND CHEMICAL.

1. A vertical lode striking N. 27° 45′ E. is heaved 85 feet to the left (west) by a dip fault striking east and west, and hading 56° to the north. The

same fault also intersects a second lode, dipping E. 28° 35' N. 72°, without causing any lateral displacement. Determine mathematically what movement has taken place in the country.

2. Illustrate by a sectional diagram the import of the terms-Inlier, outlier, apophysis, flucan, floe, escarpment, terrace drift, deep lead, interbedded vein, contact lode, stockwerk.

3. State the grounds on which ore beds and detrital deposits should be considered distinct.

4. Explain by what natural processes metallic sulphides are converted into oxides, sulphates, carbonates, and haloids, and vice versa metallic sulphates are reduced to sulphides. Give specific examples by reference to the Broken Hill Lode.

5. State your views in regard to the conditions, dynamical and chemical, which govern the extent of lodes in depth.

6. Name the principal minerals and rocks in which gold occurs (a) free in the gangue, (b) as an ore. Give ten examples in each case.

7. Prepare a sketch section, indicating broadly the geological structure of Mount Morgan, Queensland; and explain the probable derivation of the gold-bearing sinter deposit.

8. What evidence can you adduce from known mining fields to prove a genetic connection between country rock and vein matter?

MINING.

SECOND PAPER.

Mr. F. M. Krausé, F. G.S., F.L.S.

MINING ENGINEERING.

1. In examining a new field, how would you proceed in your search for indications as to the existence of useful minerals in the locality?

2. Describe

shoading..

circumstantially the operation of

3. Give a separate diagram of the boring head (a) of a diamond-drill, (b) of a free-falling percussion drill.

4. Explain the system of pillar workings and longwall workings, and state under what conditions you would adopt one method in preference to the other.

5. The outcrop of a lode, underlying 1 in 3, runs through a property which it is proposed to exploit to a depth of 2,000 feet. State where you would fix the site of the main shaft, and what disposition you would make in regard to the levels. Give your reasons.

6. In working a lode 30 feet thick, the back of the stopes has approached to within 10 feet of an upper level. How would you proceed to remove the remaining slice of vein stone?

7. A hole three feet deep has been drilled in solid rock in the direction of least resistance, and the tamping made sufficiently firm to prevent the charge from being blown out. What would be the effect of the blast? What better way of operating can you suggest?

8. Describe by diagrams the method of timbering a cribbed shaft 12 x 4 feet in the clear, with three compartments. Show clearly mode of framing and scantlings of all necessary timbers, including skids, bearers for pumps, for catchpieces, and for cysterns, collar, and opening set of a plat.

9. Explain in detail what you consider to be the most effectual method of sinking through wet drift.

10. Describe by the aid of diagrams the use of the water trompe, air sollar, and brattice in ventilating an adit.

METALLURGY.

The Board of Examiners in Chemistry. 1. Give the chief characteristics of Gold, magnesium, mercury, tin, platinum, and the tests by which you would identify them.

2. Lead Sulphide is heated in a reverberatory furnace, and during the heating Lead Oxide is formed. Describe the nature of the further reactions which occur, and contrast them with reactions that take place in similar metallurgical operations.

3. There is a mineral sometimes associated with tin ore. Describe the necessary modifications of the ordinary process for the extraction of tin when such mineral is present.

4. You are given an alloy of silver and copper. How would you determine the percentage of each metal which it contains?

5. Name the ores of Antimony, and state how the metal which they contain is usually extracted.

6. 5.6 grammes of iron are immersed in an excess of an acid solution of cupric chloride. Describe the reaction that occurs, and give the weight of the metal precipitated.

7. Describe how Sodium is now generally prepared, and state its use in metallurgical operations.

8. Name the minerals A, B, C, D, placed before you, and state how you would chemically identify

them.

ARCHITECTURE.-PRACTICAL.

FIRST PAPer.

The Board of Examiners.

1. Under what circumstances are concrete foundations advisable? What different kinds of concrete are used, and what proportions? What weights per

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