Page:Encyclopædia Britannica, Ninth Edition, v. 10.djvu/108

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GAB—GYZ

98 “ The diversity as to illuminating power was siirprisingly great, and such as will appear incredible to any one who has not ascer- tained the facts by careful experiment. 'l'hey also found the kinds of burners in common use are extremely defective, thereby entailing upon the ublic a heavy eciiniary loss, as well as other dis- advantages.P In order to exalinine this important matter more fully, the referees, with the ready permission of the proprietors, inspected several large establishments in the city, where, owing to the preval- ence of night work, an unusually large amount of gas was consumed. 'l‘he inspection in every case confii'ined the appreliensions which the referees had fomied from their examination of the burners which they had procured from the leading s-fitting establishments. In the offices of two of the leading dai y newspapers (establishnients which consume more gas than any other), t icy found that the burners principally in use gave only 55 per cent. of light compared with the Sugg-Letheby burner, or with Lcoiii’s Albert Criitch burner, and yet the price of the last-named burner is almost identical with that of the very bad burners employed in these ofliees. Tested by the Bengel burner, or by Siigg’s new burner, the amount of light given by these imperfclct burne}i;s is only between 47 and 49 per cent. of what is obtainab e from t e gas. In a communication to the Philosophical Societyof Glasgow in 1874 Dr Wallace, the ofiicial gas examiner of that city, dealing with the rich cannel gas of a minimum illuminating power of 25 candles there supplied, estimated that there is in ordinary consumption a loss of 40 per cent. of illuminat- ing power which, under favourable circumstances, might be obtained, and that in practice, while not more than 16- candle power is procured, from 20 to 23-candle illumination ought to be readily obtainable. This universal wasteful misuse of gas is not merely a question of economy, although the aggregate pecuniary loss must be very great. It affects in no small degree the health and comfort of the consumers of gas; the products -of combustion of the purest gas vitiate the atmosphere, and overheat the apartments in which it is burned. Moreover, the light from gas properly burned is much steadier and purer, and less trying to the eyesight, than that wastefully consumed. The principal circumstances which demand attention in the fitting of burners are the average pressure and illumin- ating power of the gas to be consumed. How pressure may be controlled has already been shown in connexion with governors. The quality or illuminating power of gas has a most important bearing on the nature of burners proper for use, so that a clear distinction must be drawn between common coal-gas and cannel-gas, the burners for the one kind being quite unsuited for the other variety. The maximum amount of light is obtained from any gas just at that point where the flame is on the verge of smoking, and the conditions under which 14-candle gas would be per- fectly consumed would, with 26 or 30-candle gas, produce a large amount of smoke. Indeed, the richer gas is, the greater is the difficulty in developing its full illuminating power, and at all times it must be burned in a much thinner sheet or stream than is proper in the case of poor gas, which requires less access of air for its complete luinini- f ..-rous combustion. The opening or slit in burners used for common gas is therefore much larger than in those devoted to the consumption of cannel-gas. There are two principal kinds of burners in use—Argand and flat-flame burners. The Argand burner in its usual form is useful only for common or low illuminating power gas, and it has, in the hands of various inventors, especially by Mr William Sugg of London, been so improved that for amount and steadiness of light it leaves little further improvement to be hoped for. The common Argand consists of an annular tube with a circle of small holes pierced in the end of the ring.‘ It thus produces a circular or tubular flame, which requires to be protected with a glass chimney, by which the =_ vlmission of air is regulated. The burner made by Sugg in 1869, known as the Sugg-Letheby, or Sugg’s N o. 1, is the standard burner adopted for the United Kingdom in Acts of Parliament, and the same standard has been GAS adopted in the United States, in Canada, and in various European states. At the time it was made, the Sugg No. 1 was esteemed the best known burner, but since that time Mr Sugg has perfected his London Argand, whereby with London gas results equal to about 2 candles better than the standard are obtained. Fig. :20 is a sectional view of Sugg’s London Argand with the latest improvements. At the point at which the gas enters is a brass nose-piece A, screwed to fit the usual three-eighth thread, intended by the iiianu- facturers of all kinds of gas fittings to receive the burner. This is drilled through its length, and slightly trumpeted at the top so as to fit the cone- shaped piece of metal projecting from the roof of the inlet cliam- bcr B. The outside of the upper portion of the nose-piece A is screwed to fit the inside of the inlet chamber B, and thus, by an adjustment of this screw by means of paper washers put on the shoulder at AB, it is possible to enlarge or decrease the area of the passage through which the gas has to pass in order to supply three tubes (two of which, C and D, only are shown in the draw- ing), by which it is further coii- duetcd to the combustion cliam- ber E. This chamber is made of steatite, a material which is capable of resisting the corrodin g action of heat or damp, and is a good non-conductor of heat. It is pierced with a number of holes, so arranged as regards size and 1iunibci' that the quantity of gas the burner is required to _ consume shall pass out at an inappreciablc or the least possible pressure. This is in order that the oxygen of the atmosphere, slowly ascending through the centre opening F, the annulus formed by the ed re of the air cone G, and the outside of the coni- biistion cliambcrfll, shall combine with the burning gas by natural affinity only, leaving the nitrogen to pass freely out at the top of the flame. H is one of the three springs which are intended to keep the chimney glass steady in its place. JJ are two of three stubs or rests for a screen, globe, or moon; and K is a peg to steady the current of air which passes up the centre opening F. lVith the View of competing in illuminating power with the electric light, Mr Sugg has recently devised a modified form of Argand burner calculated to yield a large illuininat— ing power by increased but still economical consumption of gas. These burners are made of two or more concentric Argand rings, the outer being of large diameter, and in operation they give out a large solid, white, steady flame. With London gas, a two-ring burner consuming 19 feet per hour yields 80-candle light; 3-ring burners which consume 23 feet give 100 candles; 4—ring burners fed with 45 feet of gas gave an illuniinatiou equal to-2300 candles. As regular pressure is essential for the proper use of these burners, a self—acting governor is frequently fitted to them. The pressure at which the best results are obtained with London gas is about '7 inch. In a series of experiments with Argand burners made by Mr John Pattinson of N ewcastle-0n—Tyne the following results were obtained:— _.u-; FIG. 20.—Sugg's London Argand Burner. Illumin'itinn' m"mim”"g C ) ‘c feet 91- v ‘_ . '3 power per .3 Burner. u nhom-_ P 0': Cul)l;3)é' per Sugg-Lt-thcby Standard 5 '0 1'10 1 4 '10 Sugg’s London Argand 5'0 1:r90 15'90 Sugg’s Improved Loii- Q 45 16,08 17 .86 don A rgand ........ .. I H Silbcr’s Argand ....... .. 5'0 I 17 '80 11 '80 Common Argantl ..... .. 5'0 11 '20 11'20

Do. do. ..... .. 7 '0 I 17 '80 12 '70