November 1, 1918. THE COLLIERY GUARDIAN. 915 Gun Metal and Phosphor Bronze. Comparative tests between coke furnace (Baumann) and oil furnace (Buess). Tables of Costs for a Production of 300 Baumann. Coke consumption, 12-3 per cent., 36 per ton ................................ 5s. 6d. per hour ... stands, average life 40 tons 1,500 charges, 37^ each ... ........ tons Tons. £ s. d. 53 7 0 13 i 6 8 93 15 0 6 0 0 53 2 6 336 4 0 £555 15 2 88 10 0 38 6 8 76 17 6 5 0 0 36 0 0 66 0 0 £310 14 2 18 cwt., at 30s. Power, 960 hours, at Crucibles, including charges for 300 crucibles at 50s. Lining, four times at 30s. Wages for furnacemen, 125 days at 8s. 6d. per day .......................................... Loss in melting, average percentage of 1-62 per cent., 4 tons 19 cwt. ... Buess. Oil consumption at 9-8 per cent., 29-£ tons at 60s. Power, 1,380 hours at 5/6 8 h.p. Cost of crucibles, including stand, average life 40 charges per 300 tons, 1,500 charges, 374, crucibles at 41s. ... Cost of lining twice and one cover Wages of furnacemen (7£ tons cost 18s.), 300 tons ..................... Loss in melting at average cent., 18 cwt. 7| lb. ... percentage 0-3 per Baumann Buess £555 310 15 14 £245 1 0 Saving in favour of oil. Discussion. Mr. Brayshaw pointed out that in comparing the relative costs of gas and oil Mr. Baillie took as the basis, in the case cited, gas at Is. per 1,000 on. ft., less 5 per cent., calorific value 660 B.Th.U., and worked out a figure of 51 -3d. against 45-9d. for oil yielding the same number of thermal units. As they were burned by different methods the question of effi-j ciency came in, and the comparison was not quite fair to oil. Gas had never been obtained in Manchester at the price quoted, and even in pre-war times they did not get it at anything approaching 660 B.Th.U. Taking 3,000,000 units, a reasonable proportion would be 45d. for oil and SOd. *for gas. The comparison between gas and coal was interesting. In the case cited the basis was a furnace burning 1J tons of coal at 12s. per ton, and the cost was worked out at £22 Is., against £15 14s. lOd. for oil. Taking the calculation in another way, he suggested that the true comparison was that 8,000,000 B.Th.U. in oil cost Ils. 8d., and did the same work as coal costing 18s. Mr. S. Boswell said he had a fair experience of trying oil fuels for boiler purposes when coal was scarce, but when the emergency was over and coal came within reach at reasonable prices the oil burners were dropped off. There was trouble from carbonising and the presence of sulphur. The Lancashire manu- facturer would readily adopt oil if he was shown that there was a saving from its use. He certainly did not pay his coal bills with complacency. A mixture of 50 per cent, creosote and 50 per cent, pitch was now being used, and at one or two places in the Manchester district the results were as good as those Mr. Baillie had stated, but the people who came to see could not make out how it was done. Mr. W. G. Gass stated that some years ago his firm put in a singeing engine which used gas produced from Scotch shale oil, and the results were very satis- factory. He did not know whether similar results would be obtained from petroleum. Their experience of using oil fuel to melt brass was disastrous. They got a tremendous heat which burned away the walls of the furnace; in about a couple of hours they had the bricks running down almost in liquid form. The support on which the pot rested was burned away, and a hole was burned in the side of the pot and the metal ran out. Mr. C. Bentham pointed out that a diagram com- paring coal and oil on locomotives showed a ratio of 90 tons of coal with 60 tons of oil. In his comparison of costs, the author took coal at 20s. lOd. per ton, and oil at 50s. per ton. Upon that basis the loco- motives must have been more expensive to run with oil. Mr. W. Fox asked what happened with locomotives engaged in shunting operations. How was the flame maintained ? The Chairman (Mr. J. Butterworth) said when the coal strike was on, six or seven years ago, nearly all of them had to go on oil in some form or other. His results certainly were not comparable with coal. Possibly it was because he had to extemporise burners of a very crude character and a flame bed, and use steam where air would probably have been better. He had expected a lot of questions tending to elicit valuable information in case they should be in the same boat again. It was quite possible that they would be liable to that sort of thing periodically during the next few years, and all* of them would have to do the best they could to keep the works running—of course as economically as possible. Mr. Baillie said the figure of Is. per 1,000 cu. ft., less 5 per cent., was given them by a manufacturer in the Birmingham district. The 660 B.Th.U. was also a manufacturer’s estimate at the time he queried it as being too high. With reference to the com- petition of fuel oils against coal for direct steam raising in this country, he did not think they would be able to compete successfully at least for some time after declaration of peace. The figure of 18-8 lb. of coal per square foot of grate was very low for a marine boiler, but it was the figure obtained when they were getting the power station engineers in London to interest themselves in the matter, and they took it for what it was worth. No doubt the efficien- cies obtained would be much greater if the coal con- sumption was at a proper rate. He had no experience of the use of producer gas obtained from shale oil, but his opinion was that if it was desired to get pro- ducer gas from Mexican fuel oils they would have to try what was termed gas oil at a price 50 per cent, higher than the ordinary oil. With an efficient burner system they could use the lower priced fuel oil and obtain the same result, and if the consumption was slightly higher, it was justified by the difference in price. The figures of 20s. lOd. and 50s. per ton for coal and oil respectively were taken as market prices at the time they were carrying out a series of experiments as to the economical use of a mixture cf coal and oil. The 90 and 60 tons in the diagram referred to by Mr. Bentham were, he believed, taken on a weights basis, and he would look into it and reply in writing. In the shunting work he assumed that the damper plates would be closed down and kept as tight as possible. Under these conditions he had known the flame to ignite without the aid of a torch after almost half an hour. A point was made that oil was used during the coal strike and then discarded. That might be due to imperfect burners not giving proper atomisation to the oil, and the regulation of the air supply might be defective because of the hurry with which the thing was done. For boiler purposes with a modern pressure jet system everyone could obtain the same figures as in the tests at the factory which had been described. They were working tests by the engineer. The engineer based his calculations on them, and he would take care to be on the right side. AIR-COMPRESSOR TROUBLES. By R. J. Bailey. Some time ago a small be’.t-driven vertical air-com- pressor was installed in a certain boiler-room where there was considerable dust due to handling coal and a’shes. It was necessary to extend the lA-in. inlet pipe outside of the building. As the unloader A was of sensitive construction and as the least bit of dirt would make the pistons stick, causing poor regulation, con- siderable power was wasted because of the safety valve on the receiver releasing continually. Jt was desired to connect the pipe as direct to the compressor and with as few fittings as possible, which located the end of the suction pipe between the eaves of three roofs. To keep it free from water and other obstructions, a hood was made, as shown at B, from 6-in. galvanised sheet metal pipe with a 2-in. sheet- metal pipe on the inside soldered to a 2-in. galvanised pipe nipple. These parts were all taken from used material found about the factory. This arrangement has worked satisfactorily for nearly a year, and it has never been necessary to clean out the unloader nor has there been any trouble from poor regulation. For lubricating the cranks, crosshead pins and pistons, four or five gallons of a certain quality of engine oil was put in the crank case when the machine was first installed. After a few days the oil was found unsuitable for this class of work, because, being thin, it would work past the pistons—which are exposed at the crank end—to the oil reservoir and about one pint per 10-hour run would pass through the valves and discharge pipe, burning on the valve stems and springs and causing them to stick and hold away from their seats. A portion of the burned oil would work into the unloader and make trouble. An oil separator C was made from pipe fittings and two 3-in. nipples, each 6 in. long. A special air-com- pressor oil was used, and no further trouble has been experienced; less than one ounce of oil gets into the separator in 30 days. Considerable advantage was gained by using a check valve in the 1-in. discharge pipe D when it was neces- sary to shut the machine down to examine the valves or to do work on the machine under pressure. It also serves to take the strain off the discharge valves due to the hammering effect when closing. Several swing checks were used, which lasted but a week or ten days before the disc and seat had to be faced off and fitted so they would not leak. A horizontal globe check valve was then used, with the disc guided by a stem above and another below the seat. After being in service about four weeks, an examination showed that the stem and guide under the disc had worn away, the disc and upper stem and guide being in fairly good condition. A check valve of the dashpot type is recommended as the best for this service, in which the upper part of the valve disc is connected to a dashpot, which will prevent its slamming.—Power. Less Light for Hotels and Big Shops.—The Coal Con troller has decided to reduce further by 25 per cent, the lighting allowances in hotels, restaurants, and the large shops in London and the big towns, so that all illumina- tion in the. nature of advertising or attraction shall be dispensed with. The revised scale is subject to any special circumstances where the further reduction would be un- fair. With regard to domestic electric lighting, it has been arranged between the Coal Controller and the prin- cipal electric light undertakings that from October 1 the minimum charge shall be extended over the year, and not be a fixed charge for each quarter, as formerly. STATE TRADING. Mr. W. L. Hichens, chairman of Cammell, Laird and Company Limited, in the course of a lecture on Wednesday on “ The Functions of the Government in Relation to Industry ” at a meeting at Saddlers’ Hall, arranged by the Industrial Reconstruction Council, said that it had been proposed that the Government should nationalise the railways, all road and water transport services, the coal mines, private armament firms, shipbuilding firms, and the liquor trade; establish super-power stations for the supply of cheap electric current; undertake an extensive housing scheme; finance or take over the key indus- tries ; convert the national factories into industrial concerns and run them for profit; develop for profit selected resources cf the Empire, and be the sole pur- veyor of the prime necessities of life. Apart, however, from the fact that State trading tended to create international complications and a large army of Civil Service voters, whose material prospects might be better promoted by one candidate than another, the organisation of a Government De- partment must necessarily differ from that of a private business. The organisation of public and private services was necessarily different, because they were primarily designed for different purposes, and delays, circumlocution and red tape were largely inevitable in a Government service. State trading also elimi- nated competition and introduced a rigid uniformity of administration which resulted in stagnation. A healthy competition was the life-blood of industry, and diversity of method was the best guarantee of progress. The State would not dare to take the risks that private enterprise did and must take if it was to be successful. Further, by entering the arena of trade the State lost the detachment and impartiality expected from the ultimate controlling authority. It became an interested party, and its decisions were at once suspect. The primary function of the Government in rela- tion to industry was to determine the conditions under which industry should be conducted by private indi- viduals, firms or corporations, and to see that those conditions were carried out. To secure the confidence of both employers and employed, it should be recog- nised as being disinterested, and if it was itself to be the largest employer of labour it would disqualify itself as the final court of appeal. Employers and employed should, in the first instance, hammer out their differences among themselves. But if they failed to agree, or if their agreement was against the public interest, the final decision, which should be binding on both sides, must rest with the Government elected by the whole community. There must be some outside and impartial authority to resolve the difference of VALVC the two parties, or the result would be anarchy. It was the Government’s business to stop profiteering and to stop exorbitant wages; to determine in the last resort the hours and general conditions of labour, and to hold the scales of justice evenly between labour and capital. The secondary functions of the Government included the promotion of industrial research, the development of the consular services, the support of the key indus- tries, and the elimination or prevention of wasteful competition. It was for the State, for instance, to step in and insist that railway co-ordination was carried out on right lines. A broad and compre hensive scheme for the supply of cheap electric pqwer through big central stations was of vital importance to industrial development. The Government should lay down the conditions under which these super- power stations might be erected, but, having done this, should leave the actual work to be carried out by private enterprise. Coke Oven Industry.—The annual dinner and meeting of the Coke Oven Managers’ Association was held at Man- chester on Saturday. Sir Keith W. Price, of the Ministry of Munitions, proposed “ The Coke Oven Managers’ Asso- ciation.” He said references had often been made to the vexed question as to how much this industry had been dependent upon foreign capital and skill. If there was one thing certain after the war it was that this had got to cease. The industry must be British to the core. The president (Mr. Hollingworth) said he considered that it was due to their industry that enquiries should be insti- tuted based on information as to the best methods of dealing with the raw materials they used. We had suffered too much in the past from the individual secrecy which had been considered advantageous to individual firms. They also felt strongly that coking coal should go to the coking industry, and when they had, been fully satisfied the remainder could be used for domestic and industrial purposes.