173 ___________________________ January 28, 1916. ______________________________ underside, is supported by means of a clamp, fitted with, indiarubber stopper, with two holes, through one of which passes the thermometer for taking temperatures, whilst the other gives passage to the contact-making device for cutting out the light of the filament lamp. Terminals are mounted on a piece of ebonite supported by a clamp for carrying the platinum wire arrangement. A length of copper tubing, about in. diameter, conveys the gas to the glass cylinder, and is connected by means of a piece of in. indiarubber tubing to aspirators (not shown), containing the gas mixtures to be tested. The electrical measuring instruments for taking voltage and current consumption comprise a 0-6 voltmeter and 0-1 ampere reading milliamperemeter. The illustration shows the connections and switches, with the method of taking the readings. Fig. 3 shows the arrangement of circuits in the experi- mental apparatus. The switch arrangements enable the lamp and the platinum wire device to be placed in parallel or in series, and also enable the platinum wire device or the filament lamp to be used independently. The contact plug attached to the milliammeter can be inserted into suitable contacts to give the current con- sumption of either the filament lamp or the platinum wire, or the consumption of both when in series. The voltmeter is arranged to give the voltage of the cell. The shunt resistance is used for regulating the current sent through the platinum wire to raise it to the neces- sary temperature for catalytic action or combustion of the gas (sec results of tests). The arrangement of circuit of circuit for the cut out is also shown. The method of cutting out the light can be seen from fig. 1. Results of Tests. The following results were obtained in tests made with the above apparatus :— Condition. Appearance of filament. Amps. Volts. All resistance in..... Just noticeable dull red 0’61 ... 2T8 One cut out......... Moderately bright red 0’65 ... 2’18 Two ,, ......... Fairly ,, „ 0’67 ... 2'18 All resistance cut out „ ,, ,, 0’70 ... 2’18 In these tests the ammeter was inserted between the resistance and the platinum filament, and the lamp was out. The voltage lines were direct to cell. (Sec fig. 1.) Condition. Appearance of filament. Amps. Volts. All resistance in .... Lowest limit of visi- 0’575... 2’15 bility of dull redness. One cut out .... Just dull red 0’615... 2’15 Two „ .... Moderately bright red 0’635... 2’15 All cut out .... Fairly „ „ 0’665... 2'15 In these tests the ammeter was still inserted between the resistance and the platinum filament, only the lamp was on. Voltage lines on cell direct. Condition. Appearance of filament. Amps. Volts. All resistance in .... Lowest limit of visi- 1’31 ... 2'15 bility of dull redness. One cut out .... Just dull red 1’35 ... 2’15 Two ,, All cut out .... Moderately bright red 1’375... 2’15 .... Fairly 1’39 ... 2’15 In this case the ammeter was inserted on the main line between the cell and the middle lamp terminal. Voltage lines on cell direct. Both the platinum and the lamp were in circuit. In the same condition as immediately above, but with the platinum wire and resistance cut out of circuit by opening switch C, thus giving only current used by the lamp, the ampere = 0-75 at 2-15 volts, and connecting up both resistance, platinum wire, and lamp in series, the results were as follow :— 1 Condition. Appearance of filament. Amps. Volts. All resistance in..... No redness visible . ... 0’51 ... 2T5 One cut out......... Ditto ... 0’53 ... 2T5 Two ,, ,......... Ditto ... 0’54 ... 2T5 All resistance out... Ditto ... 0'56 ... 2’15 The lamp in all these last tests was just glowing. On substituting a 4-volt cell for the above 2-volt one : Condition. Appearance of filament. Amps. Volts. All resistance in______ Bright red....................... 0’715... 4’1 One cut out......... Ditto ........... 0’735... 4’1 Two „ ......... Ditto ........... 0’745... 4’1 All resistance out... Ditto ........... 0’76 ... 4’1 On passing coal gas 3J per cent, past platinum spiral with everything in series, and a 2-volt cell, there was a loss of 0-015 ampere. There is great difficulty in pass- ing gas so slowly in the apparatus, so as not to cool, instead of heat, the platinum; it would be well if the gas entrance was not directly under the platinum.* The difference in temperature by a Fahrenheit thermometer placed close to the platinum wire was : In air 98 degs. Fahr.; in 3J per cent, mixture of town gas (coal gas) and air was 111 degs. Fahr.—a difference of 13 degs. Fahr. The platinum wire used in all these experiments was wire of the No. 40 gauge, Jin. in length. These experi- ments show that No. 40 gauge wire is too large, and that a smaller wire will have to be used in order to consume less current. The filament lamp in this case took 0-75 ampere current; therefore there is left a balance of 0-25 to bring the cell to its full discharge rating, viz., 1 ampere. The cell used was a Fuller’s patent block accumulator type M.L. (such as is used in the Hailwood miners’ electric safety lamp) of 2-volt 12 ampere hour capacity. The thermometer was graduated in 10 to 400 degs. Fahr., but the bulb did not pass right through the cork. The bulb proper is about an inch in length, but only about 4 in. passed through the cork, so the temperatures are not quite correct. The point of the bulb was f in. away from the wire, and above it. The firedamp used in these experiments was obtained from the Standard Collieries, Ynyshir. The device for attachment to electric lamps weighs about 2oz., and does not complicate the lamp in any way. It is well * This has since been rectified. THE COLLIERY GUARDIAN. _____________________________________________ protected from air currents and coal dust, and there will be absolutely no danger of igniting the gas outside the lamp, two or more layers of gauze being placed between it and the outside air. Experiment with Wires of Various Sizes in Firedamp. (1) Wire No. 40 gauge, about Jin. in length. Volts 2-125. Wire very bright red. Filament lamp not in circuit. Room temperature 66 degs. Fahr. Current switched on, and thermometer read 121 degs. Fahr, (after 10 minutes). Admitted gas. Wire raised to intense white heat, then fused. Repeated (after renewing wire) several times with same result. The filament (platinum) was directly on the cell, with no resistance in circuit. (2) Wire 40 gauge, about Jin. in length. All resist- ance in, and with filament lamp in circuit. Volts 2-1. Room temperature 64 degs. Fahr. Thermometer reading (after 10 minutes) 105 degs. Fahr. After admission of gas, wire became raised to whiteness. Wire originally glowing fairly bright red. (3) As above, but with two resistances in. Tempera- ture reading 110 degs. Fahr, (after five minutes). Wire glowing brighter than in preceding. Admitted gas. Wire raised to incandescence. (4) Wire 0’057 in. diameter (about Jin. length). Volts, 2-0. Lamp in circuit. One resistance In. Room temperature 70 degs. Fahr. Thermometer reading (after 10 minutes) 130degs. Fahr. Wire red. Admitted gas, wire raised to very bright redness. (5) Repeated above, with no resistance in circuit and with lamp in. On admission of gas, wire raised to a white heat. (6) Wire 0’053 in. diameter (about J in. length). Lamp in. One resistance in. Volts, 1-95. Room temperature, 70 degs. Fahr. Temperature after 10 minutes, 128 degs. Fahr. Gas admitted. Wire raised to incandescence. The voltage of the cell was getting low in these] last experiments, owing to cell approaching end of discharge. (7) Wire 0’048 in. diameter, 0’001 (area of cross- section). Length about y3? in. Volts, 2’0. Lamp in circuit, and all resistance out. Room temperature, 69 degs. Fahr. Temperature (after 10 minutes), 91 degs. Fahr. On admission of gas, wire raised almost to whiteness. It is found that wire about yj- in. in length, 0-048 in. in diameter, and 0-001 area of cross section, will give Hie desired result, and is the most suitable wire for the purpose. There is one point in these experiments to which the attention, particularly of electric safety lamp makers and filament lamp makers, is directed. In the experi- ments with coal gas, the gas repeatedly ignited when the platinum filament was raised to a bright intense white heat (incandescence), but in no case was there an ignition with methane, although the wires were raised to a much more intense white heat. No ignition was obtained even when the platinum became fused. Some types of electric safety lamps are fitted with arrangements for breaking the circuit in the event of the outer glass (outside the filament lamp) being broken, and possibly causing an ignition of gas in consequence of damage to the filament lamp. Possibly, by alter- ing the filament in these lamps, a lamp could be made which would be incapable of igniting methane (firedamp) should the filament become exposed owing to damage. ___________________________ In Parliament, on Wednesday, Mr. Runciman stated that interned steamers were still being used to carry coal from the North to the Thames. Patents and Designs Act, 1907 : Diamond Coal Cutter Company v. Mining Appliances Company Limited.—In the House of Commons on Wednesday, Mr. Peto asked the President of the Board of Trade whether his attention had been called to a recent, decision of the Court of Appeal, given on October 20 last, in the case of the Diamond Coal Cutter Company v. the Mining Appliances Company Limited; and whether, in view of that decision, he would introduce legis- lation to ensure that a licensee of a British patent vested in an enemy should not be exempt from the operation of section 36 of the Patents and Designs Act, 1907, and should not be entitled with impunity to threaten the owner of another British patent with legal proceedings for alleged infringe- ment of the enemy’s patent.—Mr. Runciman said his atten- tion had been called to the decision of the Court of Appeal, but he did not think that any legislation was necessary or desirable. Institution of Electrical Engineers : Grants for Research Work.—Addressing the Manchester local section on Tuesday evening last, Mr. Sparkes, president of the Institution of Electrical (Engineers, called attention to the fact that although an announcement had been made that the institution had power, on the initiative of 10 members, to deal with the ques- tion of “ alien enemies,” no action had been taken. The council, however, had again considered the matter, and though he could not tell them what would be done, speaking as president, he could say that some very definite steps would be taken to deal with it. Referring to the question of the development of research work, he stated that the Advisory Council on Research, appointed by the Privy Council, had approached the institution, and a carefully considered report comprising nine heads under which research was being pro- ceeded with, was submitted. Quite recently a reply was received to the effect that under two of those headings the Advisory Committee recommended a grant of 411,050 per annum, and there was every reason to suppose that equally large sums would be received uner other headings. TRADE AND THE WAR. It is reported that, as a result of the representations made by the Greek Government to Sir Francis Elliot, British Minister, 5,000 tons of coal are to be exported to Greece. The Glasgow Ship Owners’ Association, in its annual report for 1915, recommends that the improvement of the shipping difficulty can only be effected by more economical use of the tonnage already chartered by the Government; better co-ordination between ports and railway authorities; and suspension during the war of customary regulations regarding loading and discharging. The lack of coal, consequent on the restrictions on British exports, is being accentuated to an alarming extent through- out the whole of Spain. It is declared that existing stocks will be exhausted by February 15. Gas works and railways are threatened. In order to augment the national production, the Government will exempt coal miners from military service. At the present moment benzene is allowed to be imported into Sweden free of customs duty, but the Board of Trade are in receipt of information to the effect that the Swedish Board of Trade has recommended to the Government certain measures for the encouragement of the manufacture and use of “ sulphite spirit ” in Sweden, including a proposal that a customs duty of 14 ore per litre (or 20 ore per kilog.) should be levied on benzene imported into Sweden. The London County Council reports that in accordance with the terms of the Price of Coal (Limitation) Act, which came into operation on July 29, notices to contractors were duly served, and after considerable negotiations, the Council has arranged for allowances to be made by most of the contractors, resulting,, it is estimated, in a total saving of LI ,200 to Fl,300 on supplies of coal during the remainder of the contract period. The Act provides that reduced prices shall take effect as from October 29, 1915, but, in some instances, the Council, for convenience, has arranged for the new prices to operate on November 1, 1915. In conse- quence of the extra cost of labour owing to the war, in certain cases allowances have been made to contractors to slightly increase their contract prices. An interesting review of the foreign trade of Holland, covering the 11 months to the end of November last, is contained in a recent issue of the Gazette de Hollande. The most interesting point about the coal imports is that Holland is still receiving some supplies from Germany, although the total has been much reduced. In November coal imports were 486,800,000 kilogs., of which 61,100,000, 144,700,000, and 278,000,000 kilogs. came from Belgium, Britain, and Germany respectively. Net imports in the first 11 months of the year were 6,181,800,000 kilogs., as against 7,876,500,000 and 7,114,000,000 in the corresponding periods of 1913 and 1914. The deficiency thus created is only partly covered by a larger production of Limburg coal. Britain is supplying practically the customary quantity, Belgium is sending a good deal more, but Germany did not export even half the usual quantity. Yet the coal supply seems to be fairly sufficient, for thus far there has been no need to buy coal in America. Important speeches on the relation of the Avar to trade were made at the annual meeting of the Employers’ Parlia- mentary Association at Manchester, on Friday last. Sir Charles Macara, president of the association, Avho was in. the chair, spoke of the work of the association as having been eminently successful in most of the work it set out to accom- plish. In the early days of the war he strongly advocated that the Government should make use of the established organisations representing employers, as well as of those representing labour, and he was convinced that had this been done, and had close co-operation existed between the industrial, financial, scientific, transport and labour interests, and the Government, we should, as a nation, have been in a vastly better position for dealing with the crisis.—Mr. Louis Sinclair, the hon. secretary of the Commercial Com- mittee of the House of Commons, deplored the fact that this country had been sleeping on her past prosperity. Something would have to be done to put our trade under departments that would look after the business and com- mercial welfare of the nation. The Board of Trade was overlapped by the Home Office and the Colonial Office. The Home Office looked after factories and workshops and, as they knew, the consular department was drawn from the Foreign Office. Some of our vice-consuls had been of foreign birth; it was a foreign vice-consul who betrayed our treaty and nearly upset the congress of Berlin. Instead of the Home Office being allowed to inspect factories and work- shops it should be a Ministry of Justice, which should set up tribunals where cheap justice could be obtained for the commercial community. The consuls should be put' under the Ministry of Commerce, the duty of such a department being to look after the trade and general interests of the country. The Commercial Committee of the House of Commons was arranging for a congress to be held at Paris in March, and two important questions were put down by the Committee. One was with reference to the reform of the company laws amongst the Allied nations. The second was that it was desirable that prior to the conclusion of peace a commission, representative of the Allied nations, should be appointed to consider how best to promote the manufactures and commerce of the respective nations with a view to the greatest mutual advantage to the Allies, and the establishment of a commercial entente.—Prof. Kirkaldy urged the need for looking into our systems of organisation, both as regards capital and labour. At the end of the war German employers would be willing to carry on their busi- ness at the barest possible terms, and their workpeople would be willing to work for the scantiest of wages. How was this country going to face that situation? He favoured pre- ferential tariffs, but it would not do to rely on them alone. They would have to have the highest possible organisation of employers and workpeople. Both organisations would have to work in co-operation.—Mr. T. Gibson Bowles also spoke. ____________________________ Calendar for 1916.—Messrs. A. Hirst and Son Limited, Dewsbury, sole makers of the Crescent coal cutters, have for- warded us a copy of their Crescent calendar for the new year. The almanac is of the monthly sheet type, and is printed in a manner eminently suitable for office walls. West of Scotland Iron and Steel Institute.—A meeting of this institute will be held in the Rankine Hall, Glasgow, on Friday, February 4, at 7.30 p.m., when a paper will be read by Mr. E. Kilburn Scott, on “ The Manufacture of Ammo- nium Nitrate, etc., from Waste Gases,”