March 27, 1914 __________________________________________________ __________ 680 THE COLLIERY GUARDIAN. and take care of them as they came through an atmosphere that was dangerous for them. He did not think any man who was not trained would be able to set off alone with one of them and come out alive—he would do something wrong. To come out in the ordinary way without a light would be impossible, and if they were going to go on with that system they would have to supply electric lights with the apparatus. He repeated that he thought there should be a steady flow of oxygen in the appliances, but let them limit it, if they liked, to 4 cubic feet, double what a man wanted, but at any rate limit it, so that, however nervous a man might be, he could not go and blow the whole thing off at once, but would have 10 or 15 minutes’ life. Mr. Sutcliffe said the whole idea of rescue apparatus was exceedingly new; but, seeing the progress that had already been made, and the number of young men who were interested in it, he could not help feeling that the time might be drawing nigh when every competent miner would take an instrument in his pocket when he went to his work. It was all right to have the appliance on the surface, but the problem was to get out the miner, and in order to do that he ought to have the apparatus with him if possible. He was entirely in agreement with most of what had been said, except the speech of Mr, Lloyd. He was rather taken aback when he heard so young a man speaking so pessimistically on the matter. There ought to be nothing impossible. He urged the young men whom he saw around him to throw away pessimism. They certainly wanted to tread warily, but they should take an optimistic view. He believed a great deal was possible in the improvement of this useful breathing apparatus, and he hoped they would regard that meeting as a starting-point, leading to the time when perhaps every man would be able to carry an apparatus that would bring him half a mile through afterdamp. He agreed with Mr. Bobinson that the great majority of lives lost owing to explosions—he thought 95 per cent, would be nearer the mark than 75 per cent.—were lost through noxious gases rather than through the explosions themselves. __________________________ THE ABSORPTION OF CASES BY COAL * The experiments recorded below were undertaken for the purpose of ascertaining whether the coal is capable of absorbing gases to an extent sufficient to account for the normal or sudden liberation of gas observed in mining practice. They were conducted, partly at Alais and partly at the Lievin experimental station, with materials of the following composition:— Percentage classification in screens. Volatile * Specific Coal. (-----------A— -------matter. ‘ gravity. No. 40. No. 60. No. 200. Fontanes coal from the seat of a gas outburst 9’5 ... 29’0 . .. 61’5 ... 8T ... 8’2 ... 1’42 Molieres coal, crushed Lievin coal, 27’5 ... 38’0 . .. 24’5 ... 13’5 ... 5’3 ... 1’37 crushed — ... 1*5 . ., 98’5 ... 28’1 ... 5’6 ... 1’332 The specific gravity was determined on the dried powder by the alcohol immersion method, the slight correction to allow for the presence of air in the dry coal (about 4-0’2 per 1,000) being omitted as negligible. The gases employed in the Alais experiments were artificial methane and commercial carbon dioxide and oxygen, those used at Lievin being natural pit air and commercial carbon dioxide. The firedamp (two samples) had the following composition:—Methane, 61’5 per cent. (89 per cent.); oxygen, 6’75 (1’2); nitrogen, 31’45 (9’2); and carbon dioxide 0’3 per cent (0’6 per cent.). The experiments were carried out at both below and above atmospheric pressure. In the former case, two methods were employed, the one (a) by operating on a weight of several grammes of coal placed in a test tube over mercury, the gas being introduced in definite quantities, after producing the requisite vacuum, and the course of the pressure being then observed. In the other method (b) two flasks were used, one containing several hundred grammes of carbon, and the other serving as gasholder. Both were fitted with barometric tubes, and were adapted to be connected together and to an aspirator. In the experiments (c) above atmo- spheric pressure, a calorimeter bomb was used, being charged with 400-500 grammes of the coal under examination. The gas was introduced either directly from tubes of compressed gas, or else from a compressor. The results obtained, whilst indicating considerably smaller absorption, agree in their general tenor with those obtained by Joulin and other workers with wood charcoal—that is to say, they show the existence of a condition of equilibrium for a given pressure and temperature; an increase with the pressure, rapid at first, and afterwards gradually slowing down and appear- ing to approach a limit. This phenomenon is gradual, being incomplete in 24 hours in the case of a cubical capacity of about 300 cubic centimetres (firedamp); whilst, with carbon dioxide (cubical capacity 600 cubic centimetres) under positive pressure, the operation is still slower, and, indeed, a week must be allowed for ____________________________________________________ * F. Leprince-Ringuet. Comptes Rendus. Absorption in Cubic Metres at 0 deg. and 760 mm. per Ton of Coal. Pressure (absolute atmospheres) 0’25 0’5 1 10 20 40 60 80 Gas. Coal. Method. Tempera- ture. (Degrees.) Air Oxygen ^61’5 percent. 1 61’5 I QO Firedamp gg ” 92 190 Carbon dioxide < Lievin Fontanes Lievin yy yy Molieres Lievin Fontanes yy Molieres b c a a b b c c a c c c c c 20 18-20 30 18 50 16 18 16 18 27 18 8 18 0’75 0’5 5’6 1’5 1 6*6 | | | | | | | 1 1 Ox CH 1 CO ' 1 CD Ox 1 5’8 20 9 7’4 23 12 10’5 11’5 8’2 27 43 liq. 31 52 liq. 36 liq. 12’5 8’7 27 liq. obtaining an approximating result as regards both absorption and liberation. Finally, when a mixture of several gases is in question, or when a change is made from one gas to another, the phenomenon seems to be sDill more gradual, if not altogether incomplete. The disengagement of gas, especially carbon dioxide, occurs in puffs, which resemble slight explosions, even when the phenomenon is extremely gradual—a fact which necessitates the adoption of special precautions. The introduction of liquefied carbon dioxide is accompanied by only a relatively slight increase in the amount absorbed, when compared with the corresponding difference in specific gravity. In spite of the fact that the coals tested differed considerably in respect of both composition and the size of the grains, the results obtained are of the same order of dimensions. They are summarised in the above table. These results, without being decisive, correspond very well—as far as carbon dioxide is concerned—to the determinations of gas which have been performed in the case of sudden outbursts, and to the determinations made of the air in return airways in mines rich in this gas; hut as regards firedamp, they do not seem sufficient to explain the considerable disengagements of that gas in very fiery mines. _____________________________ Royal Commission on Metalliferous Mines and Quarries. —A meeting of the Royal Commission on Metalliferous Mines and Quarries was held on Thursday, March 19, at Winchester House, 21, St. James’s-square, S.W. Sir Henry Cunynghame, K.C.B., presided, and the other commissioners present were Mr. R. A. S. Redmayne, C.B. (H.M. Chief Inspector of Mines), Dr. J. S. Haldane, F.R.S., Mr. J. S. Ainsworth, M.P., Mr. R. M. Greaves, Mr. R. Arthur Thomas, Mr. R. T. Jones, Mr. W. Lewney, and Mr. U. Lovett. The Commission had their report under consideration. Freight Depression: The Laying Up Scheme.—The Council of the International Shipping Federation met in London on Friday, and considered the project for laying up ships to improve freights. A deputation was received from the Baltic and White Sea Conference, headed by Mr. W. J. Noble. The resolution passed by the board of directors of the Baltic and White Sea Conference was submitted to the Council. The resolution refers to the present unsatisfactory condition of the freight markets, and advises that improve- ment could be stimulated by owners refusing to make any forward engagements except on terms that will leave a reasonable return on the capital employed, and strongly urges conference members to loyally adhere to the policy. Mr. W. J. Noble, speaking on behalf of the deputation, said their object was to lay before the Council a proposal to check the unwarranted drop in freights which had recently taken place, and also to urge the Council to institute the necessary machinery for the purpose of withdrawing surplus tonnage on a voluntary basis. The proposal was one whereby the supply of tonnage might be regulated to meet the varying demand made on it by the movement of trade. Their proposal was, in effect, simply to extend the principle of insurance, or rather mutual insurance, to cover the risk of unprofitable employment of ships by an international scheme for laying up to meet these reduced demands. They suggested that the International Shipping Federation make an initial levy of, say, Id. per gross register ton upon all vessels covered by it to form the compensation fund. This would yield, on 18,481,677 tons at Id. per ton, over <£75,000. Subsequent levies would depend upon the then existing circumstances. The following resolution was adopted by the Council of the Federation : “ Having regard to the fact that the scheme proposed by the Baltic and White Sea Conference involves a new and important departure on the part of the International Shipping Federa- tion, the General Council does not feel justified in expressing any opinion upon the scheme submitted by the Conference until the views of its constituent associations have been obtained—(1) upon the desirability of the International Shipping Federation taking part in any movement for the regulation of freights; and (2) upon the scheme proposed or any modification thereof. It is accordingly resolved that the associations comprised within the International Shipping Federation be invited to consider these points and to report their views thereon at the first opportunity” RAILWAY FUEL CONSUMPTION. The cost of the fuel consumed last year upon the 28 principal railways of England, Wales, Scotland, and Ireland was as follows:— Barry ______................................. 40,456 Caledonian ......................... 448,727 Central London ..................... 8,711 Glasgow and South-Western.......... 184,301 Great Central ....................... 513,646 Great Eastern_____......................... 484,617 Great North of Scotland.............. 56,280 Great Northern ..................... 495,604 Great Noi them (Ireland) ............ 94,846 Great Western....................... 945,907 ........................... Great Southern and Western (Ireland)... 126,715 Highland ............................... 69,516 Hull and Barnsley................... 49,567 Lancashire and Yorkshire ............ 432,836 London and North-Western .......... -1,160,041 ....................... London and South-Western ................... 471,530 ................ London, Brighton and South Coast ... 272,277 Metropolitan ........................... 19,353 Metropolitan District ................... 8,265 Midland............................. 900,172 Midland Great Western (Ireland) ..... 62,009 North British ....................... 409,865 ....................... North-Eastern....................... 641,632 ........................... ........................... North London ........................... 53,528 North Staffordshire .................. 58,605 Rbymney ................................ 41,583 South-Eastern and Chatham ......... 424,210 Taff Vale .............................. 81,220 The aggregate fuel expenditure was, accordingly, £8,556,219. The distance run by trains upon each system was :— < System. Miles. Barry ................................. 2,773,397 Caledonian............................. 27,886,220 Central London ....................... 1,664,720 Glasgow and South-Western........... 12,232,914 Great Central ......................... 34,615,810 Great Eastern ......................... 30,582,919 Great North of Scotland............... 2,835,159 Great Northern ....................... 31,169,393 Great Northern (Ireland) ............. 5,505,321 Great Western......................... 76,029,665 Great Southern and Western (Ireland)... 8,385,280 Highland ............................. 3,869,486 Hull and Barnsley_____........................ 3,368,016 Lancashire and Yorkshire ............. 33,536,027 London and North-Western ___________ 76,535,989 London and South-Western ........... 25,321,434 London, Brighton and South Coast ... 16,668,519 Metropolitan........................... 5,931,191 Metropolitan District ................. 5,344,229 Midland ............................. 71,943,409 Midland Great Western (Ireland) ..... 3,498,689 North British ......................... 29,571,648 North-Eastern......................... 47,205,777 North London ......................... 2,790,178 North Staffordshire ___ __.................. 4,562,290 Rhymney ............................. 2,330,404 • South-Eastern and Chatham___________ 21,454,449 Taff Vale............................... 4,843,704 The aggregate distance run by trains during the year was, accordingly, 592,456,237 miles, the average cost of fuel per train-mile run having been 3’46d. It should be borne in mind that the expression “ fuel ” includes coal, coke, patent fuel and oil. It must still further be borne in mind that some of the railways of which we have been treating are worked by steam, others by electric current, and others by steam and electric current jointly. The proportion of the two forces in these cases is also varied, but it may be accepted as a general principle that where steam and electric current are jointly used, the use of electric current exceeds that of steam. The systems upon which electric current has made the greatest strides are the Central London, the Metropolitan, and the Metropolitan District. These three undertakings are practically wholly worked by electricity ; but the use of electric power shows a tendency to increase, also, in the neighbourhood of provincial centres, and electric traction may be expected, accordingly, to exhibit a considerable advance during the next five or seven years upon the Great Central, the Great Eastern, the Great Northern, the Great Western, the Lancashire and Yorkshire, the London and North- Western, the London and South-Western, the London, Brighton and South Coast, the Midland, the North- Eastern, and the North London. As we have been dealing with the use of coal on railways, it may be interesting to add, also, a few further details as to railway coal, coke, and patent fuel traffic.