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January 2, 1903.]

JOURNAL OF THE SOCIETY OF ARTS.

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It is clearly recognised by every one who has had practical experience in the testing of burners, that the chief factor in developing the true illuminating power of the gas is that the air supply, whilst sufficient to prevent the escape of any unburnt gas, or products, should not be fed to the flame in too large a proportion, as otherwise combustion is completed before the separation and incandescence of some of the carbon particles has had time to add its iota of luminosity to the flame, and the illuminating power is in consequence reduced.

Now the London argand was devised by Mr. William Sugg to develop the maximum luminosity supposed to be possible from a gas of between 16 and 17 candle power, and the air supply to the flame, as regulated by the

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openings at the bottom of the burner, was so adjusted as to give just the necessary amount of air for this quality. As any fal) in candle power means a reduction in the quantity of air necessary for the development of the maximum amount of light, a fall in candle power to 15.5 candles causes an overaeration, and so accentuates the loss of illuminating value. This was recognised by the Gas Referees, who, in introducing the Table Photometer, altered the rate at which the gas was burnt at the standard burner from 5 cubic feet per hour to such a rate as will give a light of 16 candles. The recorded illuminating value is then calculated from the rate of combustion, so that if a gas of less than 16 candle value were burnt, the increased quantity of gas consumed should balance the excess of air supplied to the burner.

I have made many experiments to determine the influence of the various ways in which the standard London argand could be used in testing illuminating value. For all practical purposes these are four in number.

(1). To burn the gas as in the old methods of photometry at a fixed rate of 5 cubic feet per hour.

(2). To supply gas to the burner until the flame has a value of 16 candles, and then to take the rate of flow necessary to produce this light, and calculate back what the illuminating value of 5 cubic feet would be.

(3). To burn the flame at a fixed height of three inches, which was the size of flame given by a 16 candle coal gas burning at the rate of 5 cubic feet per hour, and arrive at the true illuminating value of the gas from the consumption, as in the second method.

(4). To burn the gas at a 16 candle rate, but to fix the burner in a position which would make the light on the photoped equal to 14 candles, or to any other number of candles that may be prescribed.

I used to be strongly of opinion that the right way to utilise the London argand was always to burn the gas at such a rate as would give a flame of three inches in height, as under those conditions you have the air supplied to the burner exactly fulfilling its normal functions, the height of the flame being an indication of the distance which the combustible gases have to travel before they can obtain the volume of air needed for combustion. Many experiments made during the last twenty years have all indicated that by using the burner in this way the candle power of gases, varying from 25 to 12 candles, can be satisfactorily determined.

There is one trouble, however, in using this method in practice, and that is that it is very difficult to get an exact determination of the height of the flame. But I have found by a long and very carefully carried out series of experiments that between 17 and 12 candles the results given by burning the gas to give a flame equal to 16 candles are in such close agreement with those given by burning it with a three-inch flame that for experimental purposes they are identical, and in as much as burning it at the 16 candle rate enables one to use the Table Photometer, as constructed for 16 candle gas testing, it is manifestly better to adopt a system which requires no alteration in methods prescribed by the Referees.

This being so, we can now discuss the relative merits or demerits of testing the gas by consuming it at a five cubic feet rate and at the 16 candle rate with correction back for differences in consumption. The fact that these two methods give very divergent results directly the illuminating power falls to 15 is well known, and I think the following experiments show the reason of this divergence. Taking analyses of a 16 and 14 candle gas made during these experiments the figures.

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Air needed for complete

combustion of 5 c. ft.. 29.49 c. ft. 26.5 c. ft.

and as the air ways of the London argand are constructed on the basis that 5 cubic feet of 16 candle gas require for their combustion 30 cubic feet of air, it is manifest that with a 14 candle gas of such composition burnt at the rate of 5 cubic feet per hour, 13 per cent. more air than is needed will be supplied to the flame. The result is at once apparent when the gas is tested for illuminating value at the 5 cubic feet rate

Gas tested at 16 candle rate
Gas tested at 5 cubic feet rate

........

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a difference of about 18 per cent.

14'0

11.5

In this case the rate of flow had to be increased from 5 cubic feet to 5'7 cubic feet to obtain the 16 candle power flame, an increase in gas of 14 per cent., which, by utilising the excess of air to the best advantage, brings the illuminating value up to the standard which

It is seen from this Table that for values between 17 and 15'9 candles it is immaterial as regards results whether the gas be tested at the 5 cubic feet rate, at a 16 candle flame, or a 3-inch flame, the value recorded being the same in each case, but directly the illuminating value falls below the lower limit, the 5 cubic feet rate of consumption at once begins to record an ever increasing falling off in value as compared with that shown by the 16 candle flame standard, this being due to improper regulation of the air supply to the burner, when the lower qualities of gas come to be burnt at a 5 cubic feet rate.

The only objection to burning the gas at a 16 candle rate and fixing the burner so much further from the photoped as to throw a light on it of 14 candles is that it seems unnecessary when the one correction will do all that is required.

The one point which is essential in using the London argand is that it should be used under the conditions for which it was made, and

that is with a 16 candle power flame or a flame 3 inches in height.

The duty of prescribing what shall be the standard burner rests with the Gas Referees, and they being gentlemen of the highest scientific attainments and capability, the matter can be left entirely in [their] hands. But I should imagine that, in view of the divided opinion which exists as to the fitness of the London argand as a standard burner for qualities of gas below 16 candles, and the question that arises as to the way in which that gas should be burnt, they will in all probability prescribe another form of burner better adapted for the quality of the gas that is to be tested.

It is always of interest in a case of this kind to note the causes that led to the adoption of the existing standard, and the intentions of Parliament in forming the statutes which refer to it. The holding of the scales of justice betwixt the gas consumer and the gas companies had its origin, like many other good works, with the Corporation of the City of London, as it was their special Act (the City of London Gas Act of 1868), that created Gas Referees and a Chief Gas Examiner for the metropolis, and in procuring that Act their whole desire was to obtain absolute fairness both to the manufacturer and the public.

In the various [discussions taking place in the committees of the Corporation on the subject of gas supply prior to the passing of this Act is to be found the history of the introduction of the London argand as the standard burner. It was in December, 1864, that my predecessor, Dr. Letheby, made a report on the gas supply in the City of London to the special committee appointed to consider the question, and from that report I take the following paragraph:

"Since the month of February of this year, the gas of all the companies has been tested with a burner which raises the illuminating power about 12 per cent. over that of the old burner. The construction of the burner is strictly in accordance with the provisions of the Act of Parliament, and your officer has adopted it, after much consideration, because he bas felt that, although the change from the old burner to the new is seemingly against the interest of the public, yet, if any question were to arise, in a court of law, concerning the defective power of the gas, it would, undoubtedly, be said by the companies that justice had not been done to them in the manner of testing; for, as no burner can produce light, but merely educe it, they are entitled to all the light that can be evoked from the gas by any burner which fulfils the requirements of the Act of Parliament."

It was in view of this that when the 1868 Act was passed, and the Gas Referees were created, and their powers defined, their clear duty with regard to the burner to be used for testing was laid down in Paragraph 43.

"The Gas Referees shall prescribe the burner for testing the illuminating power of the gas, and it shall be such as shall be the most suitable for obtaining from. the gas the greatest amount of light, and be practicable for use by the consumer.'

It is abundantly clear from this that the London argand was made the testing burner because it was the burner which did fullest. justice to the gas at that period, and was at the same time one which the gas consumer could utilise if he thought fit.

The conditions under which gas is consumed in developing the illuminating power are now better understood, and the Gas Referees would manifestly be quite within their powers, in the case of new Acts lowering the candle power of the gas below 16 candles, in prescribing a different standard burner.

It is perfectly well known that the poorer the quality of the gas the lower must be the pressure at which it is supplied to the flame, and the thicker must be the layer of gas prcsented to the air, the air at the same time supplied to the flame being in the case of the argand burner reduced in quantity so as not to overburn the hydrocarbons. The form of argand burner made by Mr. Sugg, for 14 candle gas, is one which undoubtedly fulfils these requirements. It is a 15 hole argand, in which trapezoidal instead of circular holes are employed for the admission of the gas, and in which the pressure is reduced from about three-tenths, as used with the London argand, to a little over one-tenth, whilst the air supplied to the centre of the flame is reduced to the required amount by the introduction of a rod which contracts the area of the central passage.

I have made a long series of experiments with various qualities of gas with the 14 candle argand and the London argand, and find that when the London argand, supplied with gas at a rate to yield a 16 candle flame, shows on correction for flow of gas that the illuminating value is between 13.5 and 145, the 14 candle argand gives the same results with gas consumed at the 5 cubic feet rate but directly the gas becomes poorer than 135, the 14 candle argand, at the 5 cubic feet rate, begins to show the same deterioration of illuminating value that the London argand used at the 5 cubic feet rate, does below 15:5

If the supply of a low grade gas of the

character demanded by the needs of the future is to bear its proper economical value to the consumer, it is clear that in defining the quality of the gas, a new burner of this description must be adopted for each quality of gas if the 5 cubic feet rate is to be retained; and if it is desired to keep the London argand as a monument of the past, it must be used in such a way as to do the fullest justice that it can to the gas. But I also think that the time has now arrived when in devising the Parliamentary requirements, a standard of calorific value should also be introduced.

Miscellaneous.

LORD CURZON ON INDIAN ART. The following report of the Viceroy's speech on opening the Exhibition of Art at Delhi on Tuesday last, December 30, is taken from The Times :

The Viceroy this morning opened the Exhibition of Indian Art in the presence of a brilliant gathering of native Princes and a large assemblage of the general public. Lord Curzon, who was accompanied by the Duke and Duchess of Connaught and the Grand Duke of Hesse, delivered an address, in which he said:

"Since I have been in India I have made a careful study of the arts, industries, and handicrafts of the country, and have lamented their progressive deterioration and decline. When it was settled to hold the present gathering at Delhi, it struck me that here was the long-sought chance to do something to resuscitate the threatened handicrafts, to show the world what India was capable of, and possibly to arrest the process of decay. I appointed Dr. Watt, who is now on my right hand, and he, with Mr. Percy Brown, his assistant, travelled thousands of miles seeing artisans and selecting specimens. Three conditions were rigidly laid down-first, that the exhibition should be purely one of arts; second, that it should contain nothing European, but only work showing the ideas, the traditions, and the beliefs of the people of India; third, that it should contain only the best-namely, everything rare and beautiful in Indian art. My object has been to encourage and revive good work, not to satisfy the wants of a thinly-lined purse. This is not a bazaar, but an exhibition; but we have added something much more important. Being conscious that taste was declining and that many of the modern models were debased and bad, we have endeavoured to set up alongside the products of the present standards and samples of the past. This is the meaning of the loan collection, which has a special hall, where you will see many beautiful specimens of old Indian art-ware lent by the generosity of Indian chiefs and connois.

seurs, some coming from our own Indian museums, some from the unrivalled collection of the South Kensington Museum. Many of these objects are beautiful in themselves, but we hope the Indian workmen here, and also the patrons who employ them, will study them, not merely as objects of antiquarian or artistic interest, but as supplying them with fresh, or rather resuscitated, ideas which may be useful as inspiring their own work in the future. This may be laid down as a truism, that Indian art can never be revived by borrowing foreign ideas, but only by fidelity to its own.

"I may be asked what is the object of this exhibition, what good I expect to result from it? I will answer in a very few words. So far as the decline of Indian arts represents the ascendency of commercialism, the superiority of steam power to hand power, the triumph of the test of utility over that of taste, then I have not much hope. We are witnessing in India only one aspect of a process which is going on throughout the world, that long ago extinguished the old manual industries of England, and is rapidly extinguishing those of China and Japan. Nothing can stop it. The power-loom will drive out the hand-loom, and the factory will get the better of the workshop, just as surely as the steam-car is superseding the horsed carriage, and the hand-pulled punka is being replaced by the electric fan. All that is inevitable, and in an age which wants things cheap and does not mind their being ugly, which cares a good deal for comfort and not much for beauty, which is never happy unless when asserting its own models and traditions, and running about in quest of something foreign or strange, we may be certain that a great many old arts and handicrafts are doomed. There is another symptom that, to my mind, is even more ominous. I am one of those, as I said, who believe that no natianal art is capable of continued existence unless it satisfies the ideals and expresses the wants of the nation that produced it. No art can be kept alive by globe trotters or curio hunters alone. If it has got to that point it becomes a mere mechanical reproduction of a certain fashionable pattern, and when the fashion changes and it ceases to be popular it dies.

"If Indian art, therefore, is to continue to flourish or is to be revived, that can only be if the Indian chiefs and aristocracy and people of culture and high degree undertake to patronise it. So long as they prefer to fill their palaces with flaming Brussels carpets, Tottenham-court-road furniture, cheap Italian mosaics, French oleographs, Austrian lustres, German tissues, and cheap brocades, I fear there is not much hope. I speak in no terms of reproach, because I think in England we are just as bad in the pursuit of anything that takes our fancy in foreign lands; but I do say that if Indian arts and handicrafts are to be kept alive, it can never be by outside patronage alone. It can only be because they find a market within the country and express the ideas and culture of the people. I should like to see a movement spring

up among the Indian chiefs and nobility for the expurgation, or, at any rate, the purification, of modern tastes, for a reversion to the old-fashioned but exquisite styles and patterns of their own country. Some day, I have no doubt, it will come, but it may then be too late. If these are the omens, what then is the aim of the exhibition and what purpose do I think it will serve? I can answer in a word. The exhibition is intended as an object lesson. It is meant to show what India can still imagine and create. It is meant to show that the artistic sense is not dead among its workmen, but that all they want is a little stimulus and encouragement. It is meant to show that for the beautification of an Indian house or the furniture of an Indian home there is no need to rush to European shops in Calcutta or Bombay, but that in almost every Indian State or province, in most Indian towns and many Indian villages, there still survives art, there still exist artificers who can satisfy the artistic as well as the utilitarian tastes of their countrymen, and who are competent to keep alive this precious inheritance which we have derived from the past. With this object Dr. Watt and I have laboured in creating this exhibition, and in now declaring it open it only remains for me to express the earnest hope that it may in some measure fulfil the strictly patriotic purpose for which it has been designed."

NEW COAl fields IN BELGIUM.

The discovery of a new soft coal basin in the province of Luxemburg, north of the City of Liège, has recently been noted, and extensive soundings have been made over a considerable area. The deposit underlies many square miles of the northern part of Belgium and the southern part of Holland. One of the veins, at a depth of from 1,000 to 1,500 feet below the surface, is from 15 to 17 feet thick, and of a very fine quality of coal, according to Consul Winslow of Liège. It is estimated that this new field contains more than 500,000,000 tons of a good description of coal, and extensive preparations are being made to open up the mines. The Government proposes to enlarge the canals in that part of Belgium, dig new ones, and open new lines of railway. The working of these mines will be more difficult and expensive than in the case of other Belgian mines, because of their depth and the presence of more water, but it is thought that this will be more than counter-balanced by the thickness of the veins. The development of this field offers an opening for the introduction of up-to-date coal machinery.

Obituary.

ARCHBISHOP OF CANTERBURY.-Dr. Frederick Temple, Archbishop of Canterbury, whose death at Lambeth Palace occurred on Tuesday, 22nd

December, had been a member of the Society of Arts since 1856, at which time he was an Inspector of Schools. Mr. Temple was one of the original examiners appointed by the Council of the Society in 1856, his subject being English History. He was joint examiner with Professor Brewer, of King's College, London. In 1859, Dr. Temple, then Head Master of Rugby, was examiner in Latin and Roman History, and he so continued until 1869, when he became Bishop of Exeter, and was succeeded by the Rev. Dr. Montagu Butler, Head Master of Harrow (now the Master of Trinity). The particulars of Archbishop Temple's distinguished career, and the expression of the wide-spread regret at his death have been so fully recorded in the daily press that it is not necessary to repeat here the incidents of his life.

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JANUARY 14." Industrial Trusts." BY PROF. W. SMART, LL.D. SIR RObert Giffen, K.C.B., LL.D., F.R.S., will preside.

JANUARY 21.-"The Metric System." By A. SONNENSCHEIN.

JANUARY 28.-"The Cost of Municipal Trading." By DIXON H. DAVIES. The LORD CHIEF JUSTICE, G.C.M.G., will preside.

FEBRUARY 4. Methods of Mosaic Construction." By W. L. H. HAMILTON.

FEBRUARY 11.-" The Port of London." By Dr. B. W. GINSburg.

FEBRUARY 18.-"Three-Colour Printing." By HARVEY Dalziel.

Dates to be hereafter announced:

"Existing Laws, By-laws, and Regulations relating to Protection from Fire, with Criticisms and Suggestions." By T. BRICE PHILLIPS. (Fothergill Prize Essay.)

"Oil Lighting by Incandescence." By ARTHUR KITSON.

"The Use of Electrical Energy in Workshops and Factories." By ALFRED C. EBORALL, M.I.E.E. "Modern Bee-Keeping." By WALTER FRANCIS REID, F.C.S.

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