December 24, 1915. 1301 THE COLLIERY GUARDIAN. ____________________ _______ branch airway only recently opened, 824 cu. ft. of the gas was produced for every ton of coal raised, and 236 cu. ft. for every square foot of freshly exposed coal. Some detailed tests made by the same observers in the area mined from the Kaiserstuhl shaft showed that gas is not only given off freely by the coal as mined, but continues to be evolved in pillar working, but diminishes steadily in volume. The diminution of gas due to Sunday holidays was very noticeable. Morin has given the results of determinations of the volumes of methane liberated in part of a mine at Li6vin, France, from 1894 to 1908, showing the relation of volume to the area of fresh surfaces of coal exposed. Taking the two extremes of the series it appears that with an area of 289,472 sq. yds. of new surface exposed in 1894 (339,765 sq. yds. in 1908), the volume of air per minute was 89,000 cu. ft. (187,600 cu. ft.), the propor- tion of methane in the air 0-19 (0*15j) per cent., and the volume of methane per minute 169 (292) cu. ft. In the oldest workings in the mine, the gross volume of methane per day steadily increased from 1894 to 1898 to much more than double, whereas the area of fresh surface exposed increased only 2-J- per cent. Then with a diminution of fresh surfaces of about 7 per cent., the volume of methane decreased nearly 25 per cent. With slight increase of area in 1900 and great decrease in 1901, the methane volume suddenly increased by more than 50 per cent, in 1900, and still more in 1901. Then began an irregular methane decline, notwithstanding a general increase of fresh surface. This diminution is explained by Morin by the fact that workings in adjoin- ing beds became so extensive as to drain some of the gas. In .the more recent workings, the methane volume steadily increased with extension of the workings, but at a much more rapid rate. These features and many other observations along various lines led Morin to believe that a large proportion of gas entering the return air is from the roof and floor, and that, other things being equal, the amount of gas increases as the workings are extended and the static equilibrium is disturbed. The figures given above do not therefore show the amount of gas given off from a stated area or tonnage of coal because the sampling was not done near the working faces. Daily Variations in Methane Emanation. Several extended investigations have been made to ascertain whether gas emanation is proportionate to the variations in activity in mining from day to day. Experiments were made by Winkler to determine the effect of no mining on Sunday. He analysed air from mines in three districts in Saxony—Chemnitz, Zwickau, and Dresden—selecting mines that were especially gaseous and others that gave off only moderate amounts. The following results were obtained, recalculated to English measures :— V olume of methane in mine air. Volume of upcast. __________ Mine. District. Week Sun- Week Sun- day. day. day. day. Cu. ft. Cu. ft. Cu. ft. Cu. ft. a min. a min. a min. a min. Lugau.......... Chemnitz 9'2 ... 8’3 ... 540 ... 8,980 Bockwa-Hohndorf Do. 25’6 ... 14'2 ...16,392 ...12,810 Deutschland ... Do. 9 3 ... 7’0 ... 6,703 ... 6,110 Brueckenberg... Zwickau 24’6 ... 11’1 ... 9,600 ... 8,974 Oberhohndorf... -Do. 4’6 ... 3’7 ... 6,636 ... 6,865 Van Arnim ..... Do. 3’8 ... 5’4 ...20,848 .21,412 Zaukeroda ..... Dresden 2’3 ... IT ... 7,560 ... 6,466 Von Burgks..... Do. 17’4 ... 22’6 ...13,907 ...15,455 Hainichen...... Do. 3 9 ... 6’4 ... 9,572 ...13,314 The Prussian commission found in the Heinitz mine in one airway when 727 men were at work that the emanation of methane was 70 cu. ft. a minute on Tuesday, whereas on the following Sunday, with no mining, the volume of gas diminished to 40 cu. ft. a minute. Tests were made by Hilt to ascertain whether the variations in methane during the day were due to barometric change or to mining. For this purpose samples were collected early in the morning before work was resumed, at midday, and at 10 o’clock at night. The results are as follow :— Average methane emanation. Mine Point in Period of mine. observation. 1885. Gemeinschaft Return 2D... Oct. 5 to 10 . Morn- n GO ’ L-Q Noon. S Night. Ath-Gouley... Return ID... Oct. 11 to 17 ... 64... 62... 60 Gemeinschaft 430 m. in ... Oct. 18 to 24 ... 27 ... 31 ... 31 Do. ... Meister bed Oct. 25 to 31 ... 29... 32j.. 30 These differences, except in the third set of observa- tions, show no relation to the mining activity, but were found to be closely related to barometric changes. In the series of methane determinations in the Gemeinschaft and Ath-Gouley mines, Hilt gives the following figures, which have been arranged to show the relative amounts of methane given off on the various days of the week for four weeks. They are intended especially to show the effect of the cessation of mining on Sunday :— Methane Given off per Minute on Various Days of the Week in the Gemeinschaft Mine. Return 2D. Mon- Tues- Wednes- Thurs- Fri- Satur- Sun- day. day. day. day. day. day. day. Cu. ft. Cu. ft. Cu. ft. ( u. ft. Cu. ft. Cu. ft. Cu. ft. 144 ... 163 ..164 — . 162 .. . 149’5 . .. 149 162’5 ... 164 ... 164 . 183 .184 .. . 171 .. 139 161 ... 155 .. 171 .. 184’5.. . 191 ;. . 171 .. 186 171 ... 174’5 . ... 179’5 . .. 161’5... . 202’5 .. . 191 . — -■ — ■■■■■— ■ " ■ 159’5 ... 164 . ... 170 .. 176 ... .185 .. . 170’5 . .. 158 Methane Given off per Minute on Various Days of the Week in the Ath-Gouley Mine. Return ID. Mon- Tues- Wednes- Thurs- Fri- Satur- Sun- day. day. day. day. day. day. day. Cu. ft. Cu. ft. Cu. ft. Cu. ft. Cu. ft. Cu. ft. Cu. ft. 64’5 .. 61 .. 55 . .. 55 .. . 67 . .. 51 .. . 51’5 54 . .. 48’5 . .. 45 .. 57’5.. . 63 . .. 60’5 .. . 54 56 . .. 44 . .. 45 .. 64 .. . 68 .. 68’5 .. 60’5 66 .. 60’5 . .. 58 . .. 48’5.. . 60 .. . 53 .. — ——. — — ■ 60 . .. 53’5 . 51 .. 56 .. . 64’5 . .. 58 . 55 In each mine the methane given off increases toward end of the week. The workings in Gemeinschaft mine were largely recent, whereas in the Ath-Gouley mine there are exten- sive areas of old workings. Some of the variations were due to changes in atmospheric pressure. Liveing made some tests in part of the Boldon mine to ascertain whether cessation of working for a few days caused diminution in gas emanation. The ventilating air varied in volume from 7,900 to 10,435 cu. ft. a minute, and the methane from 0-7 to 0-9 per cent. An experiment was made on two splits of an air current, one draining a face not worked for nearly a year, and the other draining fresh workings, both of about the same area. The first gave off 33 cu. ft. of methane a minute, and the fresh one 74 cu. ft., show- ing that in 12 months the diminution was about half, provided the original gas content was uniform in both splits. ___________________________ Output Output Increase or for 1914. for 1913. decrease. Tons. Tons. Tons. 1,492,315..1,160,274 .. +332,041 1,998... 2,397...- 399 691.367.. . 624,852...+ 66,515 89.913.. . 100,482...- 10,569 2,275,593... 1,888,005... + 387,588 amounted to 518,070 tons COAL MINING IN NEW ZEALAND IN 1914. The Mines Statement, drawn up by the Hon. W. D. S. MacDonald, Minister of Mines, gives the following particulars of coal mining in New Zealand for the year 1914- The output of coal during 1914 amounted to 2,275,593 tons, as against 1,888,005 tons during 1913, being an increase of 387,588 tons, and constituting a record for New Zealand. The principal activity in the coal-mining industry occurred in the Westport, Greymouth and Waikato districts. The following is a comparative statement of the coal and lignite raised during the years 1913 and 1914:— Tnqnppfinn Output Output Increase, inspection district. fop 1913 for 1914 19u Tons. Tons. Tons. Northern (North Island)..... 349,586... 440,453... 90,867 West Coast (South Island)... 1,057,564... 1,351,182 . 293,618 Southern (Canterbury, Otago, and Southland) .......... 480,855... 483,958... 3,103 Totals .............. 1,888,005... 2,275,593... 387,588 The comparative tonnage of the various classes of coal for the years 1913 and 1914 is summarised as follows:— Class of coal. Bituminous and semi-bitu- minous .................. Pitch coal ................ Brown coal..................... Lignite .................. Totals............ The total coal imports (468,940 tons in 1914), of which 449,555 tons were from Australia, and the exports totalled 307,700 tons, of which 140,010 tons were for the United Kingdom, 75,333 tons for Guam, and 53,703 tons for Australia. The only new colliery of importance opened during the year was that of the Waipa Company, which produced from its mine at Glen Massey, near Ngarua- wahia, an output of 50,000 tons of superior lignite or brown coal. The new mine of the Pukemiro Collieries Limited, in the same locality, has not yet reached the productive stage. The number of persons employed in and about the coal mines of the Dominion during 1914 was 4,734. State Collieries. The output from State collieries during 1914 amounted to 200,188 tons, of which 128,188 tons was produced from the Point Elizabeth mine, and 72,000 tons from the newly-opened Liverpool mine. The total output from State mines was 3,906 tons greater than that of the previous year. At the Liverpool Colliery, by boring operations carried out during the year in the valley of Seven-mile Creek, a valuable seam of superior bituminous coal has been proved over an area of about 130 acres. The seam (Morgan seam) averages in thickness 17 ft., and the estimated quantity of coal already proved amounts to about 3,500,000 tons. Boring operations are still in progress, and further reserves of coal will in all probability be proved. This, the most important mineral discovery in the Dominion during the year, was made by a Government prospecting drill, and is a further tribute to the efficacy of such drills for the purpose of accurately determining the extent and value of mineral deposits. From a financial point of view the year’s business was more satisfactory than during the previous year, though the balance-sheet shows a loss of £14,152 13s. lid., owing to the approaching exhaustion of the old Port Elizabeth mine, and the fact that the new Liverpool Colliery had not been sufficiently developed to supply all requirements. The State coal mines branch was reorganised on the retirement of the late Mr. W. C. Gasquoine, who for several years occupied the position of general manager, the management being transferred to the head office of the Mines Department. Mining Accidents. In the coal mines there were seven fatal accidents, by one of which 43 lives were lost and several persons injured. This disaster occurred on September 12 at Ralph’s Colliery, Huntly, the property of the Taupiri Coal Mines Limited. The cause of the disaster was investigated by a Royal Commission, who found that it was due to an ignition of firedamp by a naked light carried in the old workings of the mine by a miner when proceeding to his work, the ignition of gas causing a concussion which raised a quantity of fine inflammable lignite dust, by which the explosion was intensified and carried to the top of the upcast shaft, a distance of about three-quarters of a mile. The Commission considered the management of the mine was, speaking generally, good, but in certain respects—e.g., the prompt carrying out of the inspector’s orders, the precautions taken against danger from gas, the ordering of safety lamps, and the examination of the old workings—it was lax and unsatisfactory. Mining Legislation. Important amendments in the Mining and Coal Mines Acts were made chiefly for the purpose of giving effect to the recommendations of the Royal Commission on Mines, and to bring the law into line with recent enactments in the United Kingdom, in the intei est of greater safety. The most important provisions in these amending Acts were in connection with ventilation and miners’ baths at metal-mines, and with safety-lamps, flameless (or permitted) explosives, ventilation, syste- matic timbering, miners’ baths, and the prevention of the accumulation of inflammable dust in coal mines. A new appointment—viz., that of an Inspecting Engineer of Coal Mines, who by virtue of his office would also be Chief Inspector of Coal Mines—was created, and was conferred upon Mr. Frank Reed, M.I.M.M., previously Inspecting Engineer of Mines. To give effect to many of the safety provisions in the amended Acts, regulations are required, and for the preparation of these a conference of the ins} ectors of mines of the Dominion was held in Wellington. As a result very comprehensive regulations were drafted, and subsequently submitted to representatives of the employers and workers at mines throughout the Dominion. The proposals were received in a very friendly spirit, and but few alterations were suggested. Schools of Mines. At the Government examination held in connection with these schools throughout the Dominion during 1914 only five students presented themselves for exami- nation for coal mining certificates. Coal Miners’ Relief Fund. As required by the Coal Mines Act, 1908, the owner of every coal-mine contributes |d. per ton on all the coal he sells, for the relief of coal miners who may be injured whilst working, and for the relief of the families of coal miners who may be killed or injured. The following is a statement of the accounts of the fund. During the last financial year the contributions amounted to £2,068 (£1,893 in 1914); allowance on account of accidents, &c., £2,782 (£1,720) ; balance £6,320 (£7,034). ____________________________ Railway Rolling Stock.—At the end of the year 1913, the railway companies of the United Kingdom had 30,727 open wagons of under eight tons capacity, of which 28,079 were in England and Wales, 725 in Scotland, and 1,923 in Ireland. They had 375,916 open wagons of a capacity of eight tons and over, of which 333,028 were in England and Wales, 36,120 in Scotland, and 6,768 in Ireland. Of covered wagons of under eight tons capacity there was a total of 20,785, of which 12,641 were in England and Wales, 3,143 in Scotland, -and 5,001 in Ireland. Of eight tons and over capacity the total was 71,165, of which 62,208 were in England and Wales, 4,786 in Scotland, and 4,171 in Ireland. Of mineral wagons of under eight tons capacity there were 4,000, of which 2,496 were in England and Wales, 1,295 in Scotland, and 209 in Ireland. Of eight tons and over capacity there was a total of 182,019, of which 103,569 were in England and Wales, 78,344 in Scotland, and 106 in Ireland. The total number of wagons of all kinds and of every capacity was 684,612, to which may be added 22,459 cattle wagons and 53,675 special wagons—boiler trucks, tank wagons, etc.—making a grand total of 760,746. This is exclusive of privately owned wagons. Coal Contract Dispute. — In the King’s Bench Division last week, before Mr. Justice Bailhache, the case of S. Instone and Company v. Speeding Marshall and Company, both of Newcastle, relating to a coal contract dispute was heard. His lordship, in giving judgment, said this dispute came before him on a case stated by the arbitrator. The question was whether certain sellers of coal were in default in not making deliveries in connection with what was alleged to be the contract. He had to consider whether the clause in the contract excused the non-delivery of the coal. It seemed to him to be quite clear that the clause referred to difficulties in supply, and the restriction of output, but did the facts bring the sellers within the protection of that clause? A rise in the price of coal had not yet been held to be sufficient excuse for non-delivery, although there might be such a rise as to afford the sellers such an excuse —such a rise as 88 per cent. But he was of the opinion that the rise in this case was not sufficient excuse. There was always enough free coal at these collieries to be bought month by month for delivery against this contract. But the sellers were prepared to run the risk of the market prices. He was inclined to think that the clause was only meant to protect them when they were in difficulties. In the cir- cumstances he must dismiss the appeal and uphold the decision of the arbitrator, with costs.