December 6, 1918. THE COLLIERY GUARDIAN. 1191 machines and conveyors are used. Sketch and describe this face in detail, showing the method of timbering and the arrangements you would make for working the conveyors and getting the coal into the tubs. State how you would arrange the shifts, and what amount of coal you would expect to get from the face per day. (60) 2. Under what conditions would you use cast iron pipes and steel pipes respectively, both in the shaft and on the roadways? (a) How would you support the pipes in the shaft? (b) Would you lay the pipes in the roadways where hauling is done, or in the travelling roads ? State the reasons for your answer. (60) 3. Under what conditions is cockering timber preferable to straight timber for supporting the roof in roadways ? Sketch the different ways of setting cockering timber, and under what circumstances is such timbering likely to become dangerous ? (60) 4. A heading is approaching extensive old workings con- taining water at a considerable pressure, which has to be drained off prior to working out the coal. The face of this heading has advanced with the usual boreholes to within a distance of 15 yards of the old workings, when it is decided to bore through without further advancing the heading. Explain with sketches how you would carry out the work from this point, stating the .tools necessary for boring and the apparatus you would use for con- trolling the water. (60) 5. To what principal points would you direct your attention in order to increase the output of coal per man from the coal face ? (60) 6. Describe the operation of boring a vertical shot hole in a sinking pit, either by hand or hammer drill. Where there is only a little water in the pit, how would you keep the hole dry when drilling, and how would you clear the hole of the dry borings ? Where the hole has to be drilled in water, how would you clean out the sludge ? A hole drilled by hand is seldom round; sketch the shape it generally takes. (60) Subject No. 2.—Theory and Practice, of Ventilation. (Six questions only to be answered. No. 2 question is compulsory.) 1. Indicate by means of the usual symbols how you would ventilate the workings of a mine shown on the accompanying plan (fig. 1) with five splits and two air crossings. (50) 2. Compulsory Question.—Describe minutely how you would proceed to remove firedamp from a large area of workings which has, owing to some special cause, become completely filled with that gas. Make use of sketches, where necessary, to illustrate your meaning. (50) 3. Make a sketch of a regulator, showing every detail. Calculate what quantity of air will pass through it when the opening is 2 sq. ft., the difference of pressure on its opposite sides equal to a column of water 1 in. high, and the weight of a cu. ft. of air 0-075 lb. (50) 4. What quantity of air per minute is passing through a mine when the combined efficiency of the engine and ventilator is 70 per cent., the indicated horse-power of the engine 90, and the water gauge 4 in. ? (50) 5. A volume of air amounting to 20,000 cu. ft. per minute in the aggregate is passing through two airways of the same length and of the same area in cross section under a pressure equal to a column of water 1 in. high. What pressure (water gauge) would be required to force the same volume of air through one airway of the same area in cross section, but twice the length of hither of the others? (50) 6. What are the chemical constituents of water, air, firedamp, and so-called blackdamp? In which of these substances are their constituents chemically combined ? In which are they simply mixed with each other? (50) 7. What influence, if any, does the employment of flames produced by burning colza oil, petroleum spirit, alcohol and hydrogen exert on the relative heights of the fire- damp cap in a given mixture of firedamp and air? With any given testing flame what difference, if any, is pro- duced in employing the same proportion of firedamp or, alternatively, ordinary lighting gas in the mixture to be tested ? (50) Subject No. 3.—Explosions in Mines, Underground Fires, and Inundations. (Five questions only to be answered.) 1. When using water or stone dust to render coal dust harmless, under what conditions might these means be objectionable on the grounds of injury to the health of the workmen ? (20) 2. How do you account for the fact that explosions more frequently extend to the downcast shaft than to the upcast shaft ? (20) 3. Describe the dangerous gases given off («) by explo- sions, (6) by fires. (20) 4. When in charge of work at a gob fire, how would you detect the presence of carbon monoxide in the air ? (20) 5. Sketch and describe a panel system of working by the longwall method for a seam of coal liable to spon- taneous combustion. (20) 6. In connection with the use of rescue apparatus, how is the supply of oxygen assured and the respired air purified ? Illustrate your answer with sketches. (20) Subject No. 4.—Machinery. (Five questions only to be answered.) 1. A loaded cage weighing 3 tons is raised 1,100 ft. in 20 seconds without counterbalance. . Neglecting fric- tion, find the total work done iff foot-pounds and the average horse-power. (20) 2. Describe in full detail the operation of sharpening a blunt pick to make it again ready for use. (20) 3. Describe the link motion for reversing engines. Illus- trate your answer by one or more sketches. (20) 4. Make a full size drawing of a % in. bolt 4 in. long with hexagonal head measuring 1-5 in. across the angles. The bolt is threaded for 2 in. Show this in the usual manner on your drawing. Do not show a nut. (20) 5. Describe an electric cable for carrying continuous current at 440 volts down a wet shaft. (20) 6. Make a sketch, taking up most of a page, of a set of post brakes with the levers for working it, suitable for a drum about 8 ft. in diameter. (20) Subject No. 5.—Arithmetic and Surveying. (Five questions only to be answered, at least two of them being from the part headed “ Surveying.”) Arithmetic. 1. If the annual output of a colliery be half a million tons, what is the average output per man, per shift, if 1,250 men work on an average 4g shifts per week? Give your answer in tons to the nearest third decimal, and in cwt. to the nearest quarter. (20) 2. A pump delivers water into a pond, with vertical sides 60 ft. by 30 ft. by 7^ ft., and fills it in 5g hours. What is the rate of delivery of the pump in gals, per min., and in cu. ft. per hour ? (20) 3. Reduce (a) 555 tons 15 cwt. 3 qrs. 20 lb. to pounds, and (6) 3,097,600 sq. yds. to statute acres, roods, poles, and yards. (20) 4. If the pre-war cost of pitwood was 9d. per ton of output, and the price of wood be now three times what it was then, what is the present cost per ton if, from economy in use and other causes, the quantity used be only 80 per cent, of the pre-war quantity ? (20) Surveying. 5. A plan of a colliery leasehold is handed to you. It shows surface lines, but no meridian. How would you lay down the present magnetic meridian on the plan ? (20) 6. A road on the strike of a coal seam meets a fault 30 ft. up, running on the dip and rise, with a hade of 60 degs. Draw a section and find the starting point, and length of a stone drift rising 1 vertical to 10 horizontal in the line of the road to strike the seam on the upper side of, and at the fault. Scale for section 1 in. to 50 ft. (20) 7. What tests would you apply to a straight edge and to a spirit level before using them in levelling? (20) 8. A seam rises directly to the north 1 in 3; find by calculation, or by construction, the bearing of a slope heading in the seam at an inclination of 1 in 6. (20) THE AMERICAN COAL TRADE. In consequence of the sudden ending of the war, America finds itself at present with an unknown demand at home, but with a productive capacity equal to coping with a world shortage of coal and other things. Under the circumstances (says Black Diamond, •November 16), a certain collapse of the American coal market seems inevitable ; that is, the number of regular shipping mines have increased from, roughly, 5,000 to, roughly, 7,500, in addition to other sources. The productive capacity of the regular shipping mines had been increased from an actual output of 575,000,000 tons to an actual output of upward to 700,000,000 tons. Evidently there must be some re- adjustment of the production programme, or a com- plete collapse in prices in response to the law of supply and demand. Facing the new facts of the national coal situation, the coal men have been trying to readjust themselves to an unknown future. No one knows, as yet, to what extent the restoration of normal business will supplant the war industries in the demand of coal. No one knows, as yet, to what extent the demand for the replenishing of exhausted stocks of goods will supplant the orderly demand of the Government for munitions of war. The tendency at the moment is to discount a pessi- mistic future. It is to assume that normal industry will not demand coal which was called for by the war activities. The other possible course of action is to put an artificial restraint, for a period, on coal business, and thus to allow wages to continue where they are by allowing prices to continue where they are, and, pre- sumptively, to allow all of the mines to remain in activity. Struggling to make a sound decision between these two possible courses of action, the coal men have gathered together into groups. For the minute it is enough to say that production, both potentially and actually, in every district is ahead of demand in every market, and the coal situation is just as easy as two weeks ago it was tight. Indeed, the market is so easy that a curtail- ment of output due to the celebration of peace and to the last effects of the influenza epidemic has not been great enough to reduce the supply even to equal the demand, to say nothing of falling below it. One effect of the ending of the war was to release a larger amount of coke for domestic purposes. Restrictions on anthracite are increased rather than diminshed as the recent situation seemed to warrant. The fuel administration, having given miners an astounding increase in wages, announced a new price. OBITUARY. Mr. Robert W. Cochrane, aged 43, colliery viewer to the Earl of Lonsdale, died on Friday from influenza. The death is announced of Mr. M. P. Whitefield, who has occupied a prominent position for many years in the paten" fuel industry. For nearly half a century he was associated with Gueret I imited, and for more than 30 years served as manager of the Anchor Patent Fuel Department, taking the leading share in drafting the plans for the proposed extension of the company’s operations, which were held up on account of the war. On Friday, Mr. J. Hallett, of the firm of Hallett and Dickson, Caidiff, agents for the Coalbrook Collieries, died at his residence in Penarth. He was only 39 years f age, and the cause of death was pneumonia. His firm are also agent; for Messrs. Flack and Co. coal exporters, of London. Mr. R. B. Starkey, of Ellistown Collieries, Leicester, and Mr. R. C. Morgan, of Cannock Collieries, died on Sunday last. Both were well known on the London coal market, and highly respected. Destinations of Coal Shipments in 1917.—The annual statement of the trade of the United Kingdom in 1917 contains some details which have been omitted of late from the monthly Board of Trade returns relating to goods shipped from this country. The destinations are now specified, and we reproduce the -figures showing the total number of tons of coal, coke and manufactured fuel shipped to various countries in 1917, with the total for 1916 added in parentheses: Russia, 1,108.562 (5,204); Sweden, 622,067 (1,672.618); Norway, 1,191,740 (2,552,494); Denmark, 896,920 (2.456.290); Danish Possessions. 21.826 (62,031); Netherlands. 380,729 (1.347,431); France^ 19,283,220 (18.579,828); Algeria, 713,925 (868,702); French West Africa, 569.800 (210.915); Portugal, 253,823 (803,954); Spain, 835.825 (2,140,620); Italv, 4,562.072 (6.157,451); Greece, 20.165 (201.563); Tunis, 597,296 (85.631); Morocco. 23,057 (22,635); United States, 4,234 (2,300); Chile, 63,507 (83,766); Brazil, 252,128 (258,240); Argentine, 309.868 (733.153); Channel Islands, 100,531 (115.983)/Gibraltar, 1,-226.334 (517,135); Malta, 1,733,312 (84,784); Egvpt, 1.581,501 (853.757); Cape of Good Hope, 171.726 (18.354); Canada. 107.186 (3,061); British West Indies, 65,433 (20,018). IRON AND STEEL PRICES. The Minister of Munitions has fixed the export prices of all exports of pig iron, bar iron, and steel (com- mencing December 2 in each case). The existing maximum pri.es of pig iron for home delivery remain in force. The Minister is also fixing new maximum prices of steel for delivery in the United Kingdom on and after February 1,1919. Until that date the existing maximum prices remain in force. It is pointed out that the great increase in prices which would result from an immediate withdrawal of all subsidies would seriously prejudice the resumption of ordinary commercial work and induce dislocation, not only in the iron and steel Dades, but in the wide field of engineering and other activities dependent on iron and steel. The Government has therefore decided to remove the subsidies in two stages. Those applicable to steel making will be removed on January 31, 1919, when a revised schedule of maximum prices for steel will take effect. Those applicable to pig iron will continue to April 30, when it is proposed that all subsidies should cease entirely. This will involve a further readjustment of steel prices, but post-war conditions are not yet sufficiently stable to warrant the fixing of prices after that date. Arrai gements have been made in consultation with the trades concerned to secure an equitable distribution of pig iron and steel so long as any subsidies continue. The powers possessed by the Government under the Defence of the Realm Act will, if necessary, be exercised to prevent any undue holding of subsidised material. It is not, however, intended that Government subsi- dies should be used to enable exports to be made to overseas markets at less than the full cost. The Ministry has therefore issued lists of export prices for both iron and steel calculated to include the full amount of the subsidies. These prices are for delivery f.o.b. port of shipment for net cash against documents, and apply equally to makers, merchants and agents. Makers may, however, allow to merchants or agents a discount not exceeding per cent. A merchant or agent purchasing iron or steel for export shall make a declaration in writing to the iron or steel makers to that effect in respect of each such purchase. Pig Iron. Per ton. Haematite Pig Iron. <£ s. d. East coast mixed numbers 1, 2 and 3 ....... 8 12 6 Scottish do. do. ............. 8 12 6 Welsh do. do.............. 8 12 6 West coast do. do. ............. 8 17 6 Malleable Haematite Pig Iron. Refined cupola cast........................... 10 10 Cast direct fiom blast furnaces, large pig, all grades ...................................... 9 7 0 6 Foundry and Forge Pig Iron. Cleveland No. 3 foundry .......................... 7 5 Do. forge .................................. 7 5 Derbyshire, Leicestershire and Nottingham No. 3 foundry .................................. 7 2 Derbyshire, Leicestershire and Nottingham No. 4 forge.................................. 7 0 Lincolnshire foundry ..................... 7 7 Do. forge .................................. 7 7 Northamptonshire No. 3 foundry................. 7 0 Do. No. 4 forge ........................ 6 17 North Staffordshire foundry .................... 7 7 Do. No. 4 forge ............... 7 5 South Staffordshire, Shropshire and Worcester- shire, part m ne foundry........................ 7 12 South Staffordshire, Shropshire and Worcester- shire, part mine forge ......................... 7 10 Scottish No. 3 foundry ........................ 8 4 Basic Pig Iron. Cleveland .........................;............ 7 10 Derbyshire, Leicestershire and Nottingham ... 7 7 Lincolnshire ................................... 7 7 Northamptonshire ............................... 7 7 North Staffordshire ............................ 7 7 South Staffordshire, Shropshire and Worcester- shire .......................................... 7 7 0 0 6 0 6 6 0 6 6 0 6 0 0 0 6 6 6 6 6 Subject to all usual variations for quality which have been san tioned by the Ministiy for the home trade. A drawback is payable to the Government on exports of the above materials on account of subsidies. Fixed basis Ship, bridge and tank plates ...........List A 16 10 Cl Boiler plates ........................... ,, C 17 10 0 Chequer plates .......................... ,, J 18 0 0 Ship, bridge and tank thin plates........ ,, B 19 10 0 Angles and other sectional material...... ,, D 16 2 6 Small angles, tees and flats............. ,, E 20 0 0 Joists .................................. ,, H 16 2 6 Rounds, squares and hexagons ........... „ F 17 10 0 Small rounds, squares and hexagons.......... G 20 0 0 Rails, 60 lb. per yard and over ................ 15 10 0 Do., under 601b. per yard down to and includ- ing 50 lb .................................... 15 12 6 Do., under 501b. per yard down to and includ- ing 451b. per yard ........................... 16 10 0 Do., under 451b. per yard down to and includ- ing 40 lb. per yard .......................... 18 10 0 Do., under 40 lb. per yard down to and includ- ing 301b. per yard ........................... 19 0 0 Do., under 301b. per yard down to and includ- ing 2blb. per yard ........................... 19 10 0 Do , under 201b. per yard down to and includ- ing 141b. per yard ........................... 20 0 0 Do., under 141b. per yard .................... 20 10 0 Billets, per Sch. E description (A) ............ 13 10 0 Do., do. do. (B)and(C)...................... 15 0 0 Extras, same as for home sales (see authorised list). The above prices apply to steel supplied either by steel makers or re-rollers. Bar iron .......................................... 20 0 0 A drawback is payable to the Government on exports of the above materials on account of subsidies. Developments at Barrow Works.—At the Barrow Steel- works important developments are in prospect. A new blastfurnace on modern lines is to be erected. The gas- cleaning plant is being extended, and on the steelworks side several changes are being made. The steel foundries are being extended, and the company will soon be able to tackle the heavy castings required for cargo and passenger steamboats. Some important extensions may be looked for also in the plate mills.