THE COLLIERY GUARDIAN. ________________________________________________________________________________ 1276 December 29, 1916. of the gas behind the stopping. The relief pipe also serves to indicate the pressure in the fire area. When the temperature rises, the pressure is outward, and more gas escapes from the pipe; when the temperature falls the pressure is inward, and water is drawn into the pipe. After all combustion has ceased and the tempera- ture has become normal, the atmosphere in the enclosed area may alternately expand and contract. For the purpose of taking samples and determining the temperature and pressure of the imprisoned atmo- sphere, a straight pipe provided with a valve should be placed in each stopping. Samples of gas can be col- lected with a small hand pump, pressures can be read with a water gauge, and temperatures can be taken with a thermometer inserted through the pipe. Data obtained thus at regular intervals during the entire period that the fire is sealed are valuable, but their significance is governed more or less by the distance of the stopping from the fire. If this distance be great, changes in the condition of the fire will not be quickly indicated by the atmosphere behind the dam, and a change for the worse may occur before the fire fighters become aware of it. Clearly, however, in most cases the fir e can burn more vigorously only by in leakage of air through the stoppings; consequently, chemical analyses of the atmosphere just behind them show whether the inleakage of air is sufficient to keep the fire burning, and thus, perhaps, permit conditions to become worse. Samples of gas were, collected from behind stoppings that were built to seal off a fire in and close to the mouth of a drift mine working the Pittsburg bed. The first sample was taken through a hole in a concrete stopping, very near the fire, one day after the mine was sealed. The second and third samples were collected at the same place. Shortly after the third sample was taken, water which had been forced in rose so high inside the dam that more samples could not be collected. Composition of tup; Atmosphere in a Sealed Mine on Three Successive Days. © Percentage composition. § Time. t---------------------------*------------------\ GO co2. o2. co. ch4. h2. n2. 1 ... 7.30 a.m.....914 ... 1’83 ... 1’32 ... 3 60 ... 1*02 ... 83’09 2 ... 2 p.m_________8T0 ... 2’80 ... 1’61 ... 1’13 ... 0’35 ... 86’01 3 ... 8 a.m......... 8’03 ... 3’47 ... 1*36 ... 1T0 ... 0’35 ... 85’69 § Time. 1 ... 7.35 p.m...... 2 .. 1 p.m........ 3 ... 8 a.m........ The following samples were collected (also on three successive days) from the same mine by inserting a tube in a small hole driven through the thin covering over the main heading near the mine mouth. The samples thus collected represent gases from a very hot part of the. burning section. Composition of the Atmosphere in a Hot Part of Sealed Mine. CD Percentage composition. CO2. O2. CO. CH4. h2. n2"? 8’07 ... 1’69 ... 1’58 ... 3’39 ... 1’37 ... 83’90 8’03 ... 3T3 ... 1’25 ... 1’14 ... 0’29 ... 86’16 8T4 ... 3’00 ... 1’41 . 1’21 ... 0’35 ... 85’89 The analyses are interesting, because they show 'a rapid depletion of oxygen after sealing, and the forma- tion of an atmosphere that would check the progress of the fire. In other words, they show that the dams were tight and the fire was being brought under control. Samples were taken from behind another stopping, which was situated about 2,000 ft. away from the burn- ing area, by boring a | in. hole in the wooden brattice and drawing the gas into the sample container with a small air pump. Later, by using helmets, entrance was made into the mine at this place, and three samples of air were obtained at points approximately 200, 600, and 800 ft. inward from the stopping. Samples could not be collected farther in than 800 ft. because of the heavy pall of smoke encountered there. The analyses of the samples are as follow :— Composition of Atmosphere in a Sealed Area at a Point Remote from the Fire. m CO2. O2. CO. CH4. h2. n2. 1 Thro' stopping 3’47 ... 13’65 ... 0’60 ... 1’01 ... 0’18 ... 81’09 2 200 ft. beyond... 3’88 ... 11’71 ... 0’75 ... 1’32 ... 0’24 ... 82’10 3 600 ft. beyond... 4’81 ... 9’47 ... 0’80 ... 1’78 ... 0’20 ... 82’94 4 800 ft. beyond... 5’23 ... 9’38 ... 1’02 ... 1’13 ... 0’48 ... 82’66 The deficiency of oxygen in the samples was in part due to the absorption of oxygen by coal not affected by the fire. Except for the stagnant condition of the atmo- sphere and the heavy accumulation of blackdamp in the passages between this section and the burning section, the high oxygen content of the samples, especially of Nos. 1 and 2, would have caused apprehension as being sufficient to increase combustion. Because of the stag- nation of the air, however, it was felt that little oxygen from outside was reaching the fire. Air was apparently leaking in to some extent at the place where these samples were taken, or a greater oxygen deficiency would undoubtedly have been found. On account of many small openings at different places on the surface, air could not be entirely excluded. The mine was non- gaseous, and this fact accounts for the small amount of methane that accumulated directly at the fire area and at the brattice 2,000 ft. beyond. The knowledge that the accumulation of methane was slight was valuable, as it gave assurance that an explosion would not follow an accidental inrush of air. The following samples of gas were obtained on five successive days from behind one of several dams, which sealed a fire area in an anthracite mine. The dam was situated about 30 ft. from the fire area. At the time the samples were collected, air was slowly leaking through another dam, and some of the products of combustion were reaching the point of sampling. As some of these products of combustion were leaking out through the dam, compressed air was used in order to make the atmosphere outside the darn respirable while the samples were being taken. Composition of the Atmosphere in a Fire Area in an <© Anthracite Mine.* Percentage of gases found. a Time. oi f A C/2 CO,. O2. CO. ch4. n2. 1 . .. 5 p.m .. 3’5 ... 8’3 . .. 1*3 . .. 1P5 ... 75’4 2 . . 12m .. 3’8 ... 9’6 . .. 0’7 .. .. 13T ... 72’8 3 . 9.45am... . 3’4 ... 10’9 . .. 0’6 .. . 10’8 ... 74’3 4 . .. 4 p.m...... . 3’4 ... 11’3 . .. 0’6 .. . 10’3 ... 74’4 .. 4.30p.m... . 3’0 ... 12’6 . .. 0’4 .. . 9’6 ... 74’4 6 ‘ ..11 a.m . 3’3 ... 14’1 .. .. 0’6 .. 9’0 ... 73 0 7 . .. 3.30p.m... . 4’1 ... 13’6 .. .. 0’8 .. . 12’0 ... 69’5 8 . ..10.30 a.m... . 4’8 ... 10’1 .. . 1’2 .. . 14’1 69’8 9 . .. 5 p.m . 4’0 ... 12’2 .. .. 1’0 .. . 12’2 ... 70’6 12 . .. 6.30a.m.,. . 12’2 ... 6’6 .. . 0’4 .. 6’6 ... 74’2 * In all the samples the proportion of hydrogen was less than 0’20 per cent. When one of the writers arrived at the mine the fire had been temporarily checked. It increased in strength afterwards, but was again checked. At the time of the collection of sample No. 1 the fire was seemingly under control. However, the increase of oxygen shown by samples 1 to 6 caused alarm, and efforts were directed toward tightening the old dams and building new ones a few feet in front of them. The coal bed at this place dipped rather steeply, and there was difficulty in build- ing dams tight enough to hold water. Air Leakage. On the morning of the third day, the proportion of oxygen (sample No. 6) in the atmosphere of the fire area was so much larger that the fire burst forth with renewed intensity. The chute in front of the dam had filled with smoke, and there were no doubts that the fire was gaining headway. Analysis of gas samples showed a dam sealing another chute leading to the fire area to be leaking air, and efforts were directed toward making it tight. When inleakage of air was prevented by tightening this dam and building new darns in front of the old ones, water was forced to the fire. The rise of the water inside the dams prevented the further collection of gas samples. The large proportion of carbon dioxide in sample No. 10 is due to the fact that carbon dioxide from a fire extinguished had been forced into the area just prior to the taking of the sample. As stated before, the samples of gas were obtained from behind a dam situated 30 ft. from the burning area, while the products of combustion were slowly moving toward the point of sampling. External air was reach- ing the fire by leakage through another dam, and when sample No. 6 was collected, the atmosphere behind the leaking dam contained about 20 per cent, of oxygen, This dam was situated 90 ft. from the fire, and any air that reached the fire did so by slow diffusion. The percentage of oxygen in the atmosphere close to the fire was between 14 and 20 per cent. It was less than 20 per cent., because that was the content of the atmo- sphere just behind the leaky dam, but was more than 14’1 per cent., because that was the content after some oxygen had been consumed by the fire and absorbed by the unburned coal. The bed of coal was gaseous. The following analyses of -samples, collected on five successive days, behind a third dam show the accumulation of the methane evolved. This dam had been in place seven days when sample No. 1 was collected, but was not and had not been airtight, as shown by samples taken before and after those reported. Except in its early stages, the fire had no effect on the atmosphere at this place, because of the intervening roof falls. The analyses therefore show the changes in the- atmosphere within a sealed area not influenced by fire in a gaseous bed of anthracite coal. Changes in Composition of the Atmosphere of a Sealed Area in a Gaseous Mine. CD Determinations. a § Time. boa. O2. CO. ch4. N? Per Per Per Per Per 02 cent. cent. cent. cent. cent. 24 . .. 6.00 p.m. . .. 2’2 ... 15’0 ... 0’0 ... . 14’0 .. . 68’8 25 . .. 6.30 a.m. .. . 2’3 ... 14’6 ... 0’0 ... . 18’1 .. . 65’0 26 . .. 6.30 a.m. .. .. 2’6 ... 6’2 ... 0’0 ... 24’2 .. . 67’0 27 . .. 9.45 a.m. .. . 2’9 ... 5’7 ... 0’0 ... 29’3 .. . 62T 28 . .. 4.00 p.m. .. 2’4 ... 6’2 ... 0’0 ... 30’1 .. . 61’3 29 . .. 6.30 a.m. .. .. 2’8 ... 4 1 ... 0’0 ... 34’9 .. . 58’2 34 . ..12,05 p.m. .. .. 2 6 ... 3’0 ... 0’0 ... 53’0 ... . 41’4 ___________________________ The rapid oxygen decrease on the third day (sample No. 26) resulted from tightening the dam. The following analyses show the composition of the atmosphere behind a tight stopping which had been built nine months prior to the collection of the samples to enclose a fire area in a bituminous coal mine work- ing a bed that is considered non-gaseous. The accumu- lation of methane during several months’ time amounted to about 5 per cent. The oxygen had been almost entirely consumed. Before the area was entered, the samples were collected through the stoppings. When explorations were made by the use of breathing apparatus, samples were collected within the area. The fire had then been extinguished for a considerable time. The area enclosed was large. Analysis of the Atmosphere of a Sealed Area in a Non-gaseous Mine. Sample Sample ___________________________ Determinations. No. 1. No. 2. Per cent. Per cent. CO, 1’20 1’30 O, “. 0’30 010 cd 000 0’00 ch4 5’37 4’80 n2 93’13 93’80 The following table gives the composition of samples taken on four successive days, and (last sample) again after an interval of four days, from behind a stopping erected to seal a fire in a bituminous coal mine in Penn- sylvania. The samples were collected four days after the sealing of the fire. Composition of Atmosphere in a Fire Area. Percentage composition. Time. CO2. o2. CO. ch4. N>. 1.30 p.m. ... ... 4’8 .. . 1’6 .. . 0’6 .. * 4.30 p.m ... 4’8 .. . 1’6 .. . 0’6 .. * — 7.45 a.m .. 5’87 .. . 1’43 .. . 1’42 .. .’ 22’27 69 01 11’45 a.m .. 5’84 .. . 1’02 .. . 1’03 .. . 24’45 .. .. 67’66 3.20 p.m .. 5’61 .. . 1’22 .. — . 26’18 .. .. 66’99 9.05 a.m .. 5 22 .. . 0’97 .. ; 1’17 ” . 30’86 .. .. 61’72 * Not determined. The decreased percentage of oxygen in the atmosphere behind the dam demonstrates that there was no leakage of air through the dam, and also shows that the percen- tage of methane in the atmosphere increased. The authors have modified an Orsat gas analysis apparatus by adding a combustion pipette. It is easy to manipulate, and is sufficiently accurate for work at mine fires. With this apparatus, carbon dioxide, carbon monoxide, and methane can be determined within about 0’2 per cent. Hydrogen, if present in -the gas mixture, can be determined about as accurately by calculation from the combustion data. _________________________ OBITUARY. Mr. John Philip Kirkup, of Burnhope House, near Lan- chester, died suddenly on Christmas night, in his 60th year. Mr. Kirkup had been agent for Messrs. Hugh A. Ritson and Sons Limited, owners of Burnhope Colliery and South Pontop Colliery, Annfield Plain, for the past 22 years, succeeding the late Mr. Forster in that position. He was the son of the late Mr. John Kirkup, of Pelton House, Chester-le- Street, and served his apprenticeship as mining engineer under Messrs. James Joicey and Company Limited at Beamish, eventually becoming manager at the No. 2 pit. Afterwards Mr. Kirkup spent three years, as mines manager, in the Nyzam’s Territory, India, after which he came to Burn- hope Colliery. He was a member of the council of the National Association of Colliery Managers, and a past- president of that body. _____________________________________________________ THE IRISH COAL TRADE. Thursday, December 28. _________________________________ _________________ Dublin. Up to the time of closing last week there was quite a rush for supplies of coal to tide over the holidays, the severe cold also affording a stimulus to business, and in many instances orders could only be partly fulfilled by the delivery of small quantities. At the time of writing there is no change in prices, viz..:—Best Orrell, 44s. per ton net; Yorkshire brights, 43s.; best Wigan, 42s.; best slack, 36s.; retail price, 2s. lOd. to 3s. per sack of 10 st.; best coke, 44s. per ton; steam coal, from about 40s. per ton. Irish coals from the Wolfhill Collieries, Queen’s County, are : Malting, gas, and house coal, 45s. per ton; steam coal, 20s. to 40s.; culm, 12s. to 15s. per ton—all f.o.r. Athy, the nearest railway connection. The Cork Corporation last week decided to ask the Lord Mayors of Dublin and Belfast and the Mayors of Waterford and Limerick to call an all-Ireland meeting with reference to the construction of a line of railway to the Wolf- hili Collieries. A Board of Trade communication states that the Irish local authorities have been asked to deal with excessive coal charges by means of voluntary arrangements with the retail merchants, and that, in the absence of such arrangements, it has not been found possible for the Board to deal with the question of freights. The coal vessels arriving in this port during the past week were chiefly from Glasgow, Manchester, Cardiff, Ayr, Silloth, Birkenhead, Newport, Swansea, Liverpool, Preston, Point of Aire, Garston, Whitehaven, and Workington. Belfast. In manufacturing and works fuel business was rather quiet, owing to the large stocks held by the principal con- sumers, but the house coal trade was more active in conse- quence of cold weather and the Christmas holidays. Sup- plies were equal to requirements, and prices are unchanged. Current quotations for house coals are :—Best Arley, 43s. 6d. per ton; Orrell nuts, 42s. 6d.; English house, 41s. 6d.; Scotch house, 39s. 6d.; Orrell slack, 39s. 6d. per ton. Coal-laden vessels arriving during the week were from Troon, Ayr, Garston, Partington, Barrow, Ardrossan, Silloth, Whitehaven, Glasgow, and Maryport. The total number of colliers entering the harbour from December 3 to 16 was 136. THE TIN-PLATE TRADE. Liverpool. The holidays have interfered with business the last week, but the tone of the market is firm, and prices look like going higher, as works are not at all anxious to sell, in view of the further restrictions in supplies of steel, acids, and labour. Steck plates are in demand; 34s. to 34s. 6d. is being paid for I C 14 x 20, and 70s. to 72s. for I C 28 x 20. For class A orders, however, the following figures are quoted :— Coke tins : I C 14 x 20 (112 sh. 108 lb.), 28s. to 30s. a box; IC 28 x 20 (112 sh. 2.16 1b.), 55s. 6d. to 60s. a box. IC squares and odd sizes, 28s. 6d. to 30s. basis for approved specifications. Charcoals run 31s. basis and upwards, according to finish. Coke wasters are getting very scarce. Quotations are very firm, and advancing:—CW 14 x 20, 29s. 6d. per box and upwards; C W X 20, 60s. 6d.; C W 14 x 18|, 29s. 6d.: C W 20 x 10, 41s.; C W 30 x 21, 68s. AH f.o.b. Wales, less 4 per cent. The Victoria Government Gazette has published a notice to the effect that the Council of the City of Brunswick intends to borrow the sum of .£7,500 for the purpose of extending the electric lighting and power system of the city. The Board of Trade Journal states that H.M. Trade Com- missioner in Australia reports that important developments of the hydro-electric scheme in Tasmania are contemplated, and that a duplication of the existing plant will be made shortly. Everything seems to point to important industrial developments in Tasmania in connection with the hydro- electric scheme, and that the market there for electrical appliances will be considerably increased.