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"minerals." Usually the organic origin of Jet and Amber is recognised as putting them outside the category, but the mixed composition of Emery is not appreciated as leading to its being classed as a rock rather than a mineral. Some are quite unacquainted with the composition of Emery.
STAGE 3. Results : 1st Class, - ; 2nd Class, 7; Failed, 4 ; Total, 11. The few candidates in this stage show a very fair knowledge of the subject. In 1905, the students taking this stage were of exceptional ability, no less than five being awarded a First Class. This year, while the failures are one more than in 1905, the remaining candidates attain only to a Second Class standard.
The question on “Hardness-Figures” was only well answered by one or two candidates, most of them regarding the Sclerometer as only an instrument for determining comparative hardness. In one case “Exner" was taken as the name of a mineral ! In the question on the use of the polariscope, the difference between the effect seen when the rays ary parallel and when they are convergent is seldom appreciated. “Schiller" is treated by some as merely a variety of lustre, the fact that reflection takes place only in certain positions being missed. The accounts given of Uralite, Apatite, and the Stassfurt Salts are, on the whole, disappointing, and the economic questions involved in the use of certain materials for incandescent gas-mantles have apparently not been taught. On the other hand, the identification of minerals and their study with the blowpipe have evidently received much attention, and the results are satisfactory.
HONOURS. Results : 1st Class, 2 ; 2nd Class, - ; Failed, 2 ; Total, 4. Four candidates presented themselves, two of whom sent in very admirable papers that would be regarded as very creditable indeed in any University Examination, and these are placed in the First Class ; two failed.
Report on the Examination in Principles of
Mining. The following Table gives the number of candidates this year and last :
The comparison shews an increase of 93 candidates, there being a larger number of entries in Stage 3 and Honours, but a falling off in Stages 1
STAGE 1. Results : 1st Class, 236 ; 2nd Class, 417; Failed, 298 ; Total, 951. Compared with the previous year the papers in this Stage shew little change. They are up to the average of last year in matter, and shew a distinct improvement in neatness and style. The papers in one parcel are exceptionally bad, and have lowered the general average.
With regard to the questions severally, the following points may be noted :
Q. 1. What is anthracite, and what are its special properties and uses?
Where is it mined ? This question is answered very well on the whole. The only faulty portion is in regard to the uses. Even Welsh candidates, familiar with the mining of anthracite, appear to have hazy notions as to the uses of that material, and many refer to it as being largely employed in the Navy. No reference is made to its use in stoves. By a curious mental confusion several candidates describe anthracite as a dangerous explosive. Q. 2. Describe the operation of shot-firing with an explosive on the
"permitted list." (Sketches required.) In very many cases this question has been carelessly read, and much time wasted in descriptions of the actual drilling and the preparation of the shot hole. Comparatively few candidates lay stress on the essential acts that have to be performed in the interest of safety, such as the careful examination for gas, the watering of any coal dust that may be present, and the use of clay for tamping. In some cases vague ideas as to “permitted explosives" obtain, even ordinary gunpowder being sometimes regarded as an explosive on the permitted list. Q. 3. What precautions sbould be taken in withdrawing timber when the
roof is bad? (Sketch required.) This question is answered very well. Candidates appear to be fully aware of the common sense precautions that have to be taken in withdrawing timber, and generally describe the old dog and chain or one of the modern timber-withdrawing appliances. The Sylvester pulling-jack is as a rule accurately described, but generally inaccurately sketched, the candidates connecting both the withdrawing chain and the chain anchoring the machine to the firm prop to opposite ends of the notched bar. Many of the candidates can have had no practical knowledge of withdrawing timber, as they recommend, after examining, to place the setting of chocks before beginning to draw timber, so that they would use more timber than they save. Q. 4. Describe the pit-bottom arrangements at some colliery with which
you are acquainted. (Sketch required.) This is a favourite question, and is answered satisfactorily on the whole. There
appears to be a good knowledge of the arrangements for convenient and rapid handling of wagons at the pit bottom, and the different practice in various districts is well indicated. Good sketches, however, are few. Q. 5. Describe the best form of wheels for mine wagons, and the most
economical method of greasing their bearings. (Sketches
required.) This also is a favourite question ; but much time has been wasted by a discussion of the relative merits of fast and loose wheels. The methods of greasing are well and clearly described. Reference is frequently made to automatic greasers of the corrugated wheel type. In South Wales the candidates generally describe the Rowbottom wheel, loose on the axle with the oil chamber in the body.
Q. 6. In what manner should a cage be attached to the winding rope ?
(Sketch required.) The sketches given in answer to this question are poor, but the descriptions are generally accurate. Most of the candidates appear to realise the importance of a good capping to the rope, although in describing the capping many think that the rope is brought through the large link connecting the bridle chains together and then bent back and held in place by two flat
cheeks of iron. This idea is to some extent excusable, as in a dusty mine with a well oiled rope the student might easily draw such a conclusion from a casual examination of the end of the rope. Q. 7. Explain the action of the plunger pump used in mines, and state
its advantages over a bucket lift. (Sketch required.) This question is that least frequently attempted, and is poorly answered. Even from the satisfactory replies, it is obvious that the knowledge was purely theoretical. There appears to be general ignorance as to the difference between the plunger and the bucket lift. It is possible that the lack of good answers is due to the fact that the old type of engine at the surface with the rods going down the shaft has been largely displaced during recent years by the direct-acting steam pump placed underground. Q. 8. Supposing 40,000 cubic feet of air per minute to be passing
through an airway 8 feet 9 inches wide and 7 feet 3 inches high, what is the velocity of the air per
second. This question has elicited a large number of correct answers with the working clearly stated. A few give the quantity of air per second and the velocity per minute, but as a rule the ideas are correct and the mistakes made are in the arithmetic. Q. 9. Explain the action of any centrifugal fan with which you are
acquainted. (Sketch required.) Most of the answers shew a very good knowledge of the action of a centrifugal fan, but the sketches leave much to be desired. Q. 10. Describe the safety lamp with which you are most familiar, and
state the method of locking adopted. (Sketch required.) This is a favourite question, and is answered very satisfactorily with good sketches. Of those who attempt the question, about 64 per cent. describe locking by lead rivets, 28 per cent. magnetic locks, and 8 per cent. the old-fashioned screw.
BRANCH B. Comparatively few candidates entered in Branch B., many, as in previous years, being coal miners who had obviously wandered unintentionally into this Branch. Their answers are too poor to enable useful deductions to be drawn from them. There are good papers from a few classes in Cornwall and in iron-ore districts. Q. 11. Give particulars of the nature and extent of any workable
mineral deposit (other than coal) with which you are acquainted. This question when attempted elicited good descriptions of tin-ore and iron-ore deposits. Q. 12. Describe the operation of shot-firing with an explosive of the
nitro-glycerine class. (Sketches required.) This question is, on the whole, satisfactorily answered. Q. 13. What precautions should be taken in withdrawing timber when
the roof is bad ? (Sketch required.) The answers are not so good as those to the similar question in Branch A., attention being devoted to bad timber rather than to bad roof. Q. 14. Describe the operation of filling mineral into a skip in an
inclined shaft. (Sketch required.) This question is answered well, and there are some excellent sketches. Q. 15. Describe the best form of wheels for mine wagons, and the most
economical method of greasing their bearings. (Sketches required.)
The answers are poor ; one candidate, for example, states that "the most economical way of greasing the wheels of a train is to drop candle grease into the bearings”. The poorness of the answers is probably due to the fact that lubrication is not carried out so systematically at ore mines as it is at collieries.
Q. 17. Explain the action of the plunger pump used in mines and state
its advantages over a bucket lift. (Sketch required.) A metal miner ought to have been able to answer this question without difficulty, seeing that pumping engines are provided at nearly every metal mine. It was, however, rarely attempted. Q. 19. Why are the working places of quarries usually arranged in steps
or terraces ? (Sketch required.) The answers are very poor. Much ignorance is shewn regarding the nature of open-workings, and in the sketches the beds are invariably represented as horizontal. Q. 20. Give a detailed description of the various kinds of candles used
by miners, stating their relative advantages and disadvantages. The answers are poor. Candidates do not appear to be acquainted with the size and weight of candles, and rarely point out the advantages of one kind over another.
STAGE 2. Results : 1st Class, 111 ; 2nd Class, 447; Failed, 180 ; Total, 738 In this Stage, the papers, as a rule, shew that there have been most careful training on the part of the teachers and accurate and painstaking work on the part of the candidates. They are fully up to last year's standard.
Q. 21. Describe fully any deposit of fireclay, oil shale, or stratified iron
stone with which you are acquainted. This question is answered very badly. Those who attempted it described fireclay, oil shale, and ironstone in the most elementary manner. Oil shale is generally stated to be “clay or mud consolidated by time or pressure." Every student who has attempted this question uses these actual words with only the slightest variation, and all appear to be ignorant that the term "oil shale” should be confined to shale containing sufficient petroleum to permit its extraction by a process of distillation. Q. 22. Give particulars of the results obtained in the search for coa!
under the secondary rocks of this country. This question is less frequently attempted than any other, and there is not a single answer shewing an intelligent appreciation of what the question means. Many of the candidates shew a lamentable lack of knowledge of Elementary Geology, and many give theories as to the formation of coal, and the most elementary geological descriptions of Mesozoic rocks. Only three or four candidates appear to have heard of the search for coal in the south-eastern counties of England. Q. 23. Describe one of the coal-cutting machines of the disc type.
(Sketch required.) The answers to this question are generally good, but with few exceptions the sketches are poor. The question is a popular one, and the construction and mode of operation of coal-cutting machines are well understood. Indeed the answers are better than those to similar questions in previous years. Either this portion of the syllabus is receiving more attention from teachers or the machines themselves are coming into more general use,
Q. 24. Describe the method of “spilling" or "forepoling” for driving
through loose, watery, or running ground. (Sketch required.) Except that many candidates describe the method of sinking by spilling instead of driving by spilling, the answers are quite satisfactory. The confusion of spilling in sinking with driving through loose ground extends even to candidates from the north of England where the process has been largely employed, and where the term spilling" is usual. "Piling" is perhaps a more visual term in other localities. Some excellent descriptions are given by candidates who obviously have had practical experience of the process.
Q. 25. What is meant by the term “self-acting incline"? State the
conditions under which such "inclines may be used, and the precautions to be adopted for the safety of persons employed
in connection with them. (Sketch required.) The answers shew that the working and arrangement of a self-acting incline and the precautions demanded by the Coal Mines Regulation Act are well known. In some cases, however, there are hazy ideas as to the conditions under which such inclines may be used, and very crude ideas as to the gradients.
Q. 26. Describe an aerial ropeway. In what circumstances is this method
of haulage most suitable? (Sketch required.) Very few candidates have heard of an aerial ropeway. Most regard it as meaning an endless rope over the tubs. Some have vague ideas of the system and of the circumstances in which it is most suitable, but there are very few really satisfactory answers.
Q. 27. What are the chief causes of the deterioration of winding ropes,
and what remedies are used ? The answers are full and accurate. Corrosion is usually given as the chief cause It is extraordinary to find in many cases the friction caused by the rope passing over the pulley and the strains and jerks due to starting the load put down as the chief causes of the deterioration of winding ropes. These strains are not nearly so common as often believed. A good windingengine man starts his cage without the least jerk, and a good enginewright sees that both ropes are adjusted to the proper length so that no slack rope exists at the moment of lifting. In reference to corrosion, the common idea appears to be that it is entirely due to acid water. Ordinary oxidation is not mentioned and it is assumed that oxidation takes place only in wet shafts, it being forgotten that the rope is continually subjected to the action of rain and of moisture in the atmosphere.
Q. 28. What horse-power is required to lift 18,000 gallons of water per
hour from a dip working 1,500 yards distant from the shaft, the average gradient of the road being 1 in 5? The friction in
the pipes is to be neglected. This is a favourite question and the correct answer (81.81 horse power) is frequently given, and the working neatly and systematically shewn. The popular mistake is to neglect to reduce the gallons of water per hour to gallons per minute. It is curious to find candidates taking the trouble to determine the hypotenuse by Euclid's 47th proposition, or by finding the cosine of the angle. One candidate, after doing the latter correctly found the horse power to be 289,332.
Q. 29. What effect has “splitting" the air on the ventilation of mines,
and what benefits are to be gained by increasing the size of air
ways? This favourite question is answered very intelligently. The chief advantages of splitting the air are realised, and there is a general knowledge of the benefits to be gained by increasing the size of the airways.