the Christian and Pagan luck of the days of the week:

"Monday's bairn is fair of face, Tuesday's bairn is full of grace, Wednesday's bairn is full of woe,

Thursday's bairn has far to go,

Friday's bairn is loving and giving,

Saturday's bairn works hard for a living.

But the bairn that is born on the Sabbath Day Is happy, and bonny, and wise, and gay."

There were one or two other very minor points on which he might say more had he not already said so much about the days of the week. He did not quite agree with Miss Sykes' animadversions on the Mohametan law of divorce. Its spirit, at least, is most compassionate, and in its operation it at least avoids all scandal; while from Miss Sykes's own paper it is clear that the Persians treat their wives most lavishly to the best of their earthly possessions, cool rooms, exquisite carpets and hangings, tasteful furniture, the daintiest of meats, really refreshing "teetotal drinks," and those gardens of delight from which all the world derives the name of "Paradise." Again, as between the Chairman and Miss Sykes, he held that the movement towards monogamy in Persia is largely due to economical causes. He knew that the tendency toward Agnosticism in India is. To be a thoroughly good Hindu, costs much. It also costs something to be a consistent Christian, or a Muslim. It is offensive to a Muslim to call him a Mahometan. It ascribes divinity to Mahomet. Agnosticism, as a distinguished Hindu Agnostic told him some years ago, "costs nothing." The "Protestant Reformation" was largely due to economic measures. But these were matters not directly connected with the paper, the reading of which had been in every way, in its matter and its literary form, and in the very manner of its delivery, a brilliant success. He most cordially moved the thanks of the meeting to Miss Sykes.

Mr. EDWARD PENTON, Junr., in seconding the vote of thanks, said that Miss Sykes had given a description of what no male traveller in Persia could ever possibly enjoy, namely, a peep into the Anderoons. The careful way in which she had worked out the domestic life of the country was most interesting. Persia at the present moment was a much discussed country, mostly through the medium of the Press, but he thought few people took the trouble to study its domestic life. A traveller in Persia missed nothing so much as the faces of women; he went through a Persian town and saw what looked like

Friya is the Goddess of Love. The Mahometans also, at least, of India confuse the luck of the days of the week by, in counting the days of the month on their fingers, holding the days which fall on the middle finger ["digitus infamis," "d. sceleratus," &c.], i.e. the 3rd, 8th, 13th, 18th, 23rd, and 28th, unlucky,

on legs running through the streets.

ver posses Women

wore might cover the most

beautiful in the world, but the traveller could know. Miss Sykes had seen behind

the veil, and probably would be able to say whether their conjectures were correct or not. In regard to the pilgrimages, he had joined the road to Meshed at Tarbati Haidin, which might be called the "Clapham Junction" for Meshed, and the number of women setting out for the pilgrimage was simply extraordinary. Throughout the journey of about 90 miles the women were housed in most uncomfortable places, sleeping in stone rooms, with a mat placed in front of the door, and with a chance of being kept awake all night by the chatting of the muleteers, which never ceased. Miss Sykes had not alluded to the great use of opium, which it appeared to him must conduce a great deal to the laziness which was evident throughout the Eastern portions of Persia.

Surgeon Lieut.-Col. INCE asked Miss Sykes in her reply to say whether, when she visited the zenanas, she went, as most English ladies did, open-faced or whether she wore a veil.

Mr. J. D. REES, C.I.E., said that Mr. Savage Landor, in his recently-published book, "Across Coveted Lands," dwelt repeatedly on the great rudeness of the Persians. His own experience was very different, and he would like to have Miss Sykes's opinion on the subject. He would also like to ask her whether she ever came across the robbers who figured so frequently in many travellers' experiences, but of whom he saw absolutely nothing in the most robberridden province in Persia, viz., Kurdistan.

Miss SYKES, in reply, said that she had resided in Persia for nearly two and a-half years, and during the whole of that time she went about as an Englishwoman, with an unveiled face, even when she visited the Anderoons to see the women. She had always met with unfailing kindness and courtesy throughout the country. The Persians were very like the French, they had particularly good manners themselves, but naturally would easily be ruffled if not treated with courtesy. She had not yet read Mr. Savage Landor's book, and did not know where he had met the robbers; she had never come across robbers herself during her travels through Persia, but the fact of her being in the company of her brother, who was a British Consul, might have accounted for the immunity. She had, however, met a good many people who had been in Persia, and had heard from them that it was on the whole the safest country in the East in which to travel.

The vote of thanks having been carried unanimously, the meeting terminated.

CANTOR LECTURES.

"THE FUTURE OF COAL GAS AND ALLIED ILLUMINANTS."

BY PROFESSOR VIVIAN B. LEWES, Royal Naval College, Greenwich. Lecture I.-Delivered Nov. 24th, 1902. Few of the great industries have undergone such radical changes in condition as have fallen to the lot of gas manufacture during the past twenty years, and my desire in these lectures is to show how these changes have arisen and the direction in which they tend, together with such side issues as must of necessity be satisfactorily settled before the altered condition can bear full fruit for the consumer of gas, and before the gas manager can give his full adhesion to the altered state of things.

When, in the early years of last century, coal gas became a commercial reality, the one end and aim of the manufacturer was to produce his gas, and such details as purity, illuminating and calorific value, never troubled his mind. As time passed on, however, and competing companies vied with each other in their endeavour to secure customers, advantages had to be offered to coax consumers from the enemy's camp, and those who remember the battle of the two then existing City companies with another proposed rival in 1847-48-49, and the way in which the gas consumers in the City were at that time pestered and pamphletted by the supporters of the rival schemes, will realise that even in those days gas management was not a bed of roses. The outcome of the rivalry was the introduction in the early fifties of a standard of illuminating value and a string of Parliamentary requirements which have ever since safeguarded the consumer and harried the gas manufacturer.

In 1850 a Bill was passed which enacted that a consumption of 5 cubic feet of gas per hour should be equal to the light of 12 wax candles of the size known as sixes, the burner employed being a brass argand burner with 15 holes. In 1860 another Act changed the illuminating power to 12 sperm candles, which meant an increase of some 16 per cent. in the illuminating value of the gas, owing to the fact that the wax candles originally used were only equal in illuminating power to 10.3 sperm candles as at present employed for testing purposes. In 1868 the illuminating power was again raised to 14 candles, whilst, in 1876, the present 16 candle standard was reached.

The amount of light emitted by the gas, however, was still insufficient to satisfy the desires of the consumers, who, utterly ignoring the fact that the illumination to be derived from coal gas was quite as much dependent on the burners employed as it was upon the standard illuminating value, vented their dissatisfaction at the light emitted by small flat-flame burners by clamouring for a higher quality of gas; and even thirty years ago the great aim of the gasconsuming public was to obtain the highest candle-power gas that could be squeezed out of the gas company, in order that they might gain something like decent illumination from the flat-flame burners then almost exclusively used, and which were as a rule so small as entirely to destroy the value of the gas. It was at this period that the anomaly became common of seeing a town supplied with gas of over 20 candle illuminating value, swathed in semi-darkness, whilst another, with the much abused 13 or 14 candle gas, supplied at a good pressure and burnt in decent sized burners, was well illuminated.

It was at this time also that some of our most able chemists ranged themselves on the side of the votaries of high illuminating. power, and even such practically-minded men as the late Sir Edward Frankland clamoured for the introduction of high illuminating power gas, such as is produced from cannel, in place of 16-candle coal gas, the general line of argument being well shown by portions of Sir Edward Frankland's introduction to the section of his published researches dealing with applied chemistry, in which such paragraphs as the following occur:---

“Coal gas is not suitable for use in dwelling-houses by reason of its very low illuminating power-100 cubic feet of coal gas contain only 4 cubic feet of illuminating gas, the rest is mere rubbish, which heats and pollutes the air in which the gas is consumed.

.... It cannot be too widely known that coal gas, although it costs less per 1,cco cubic feet, is light for light much dearer than cannel gas."*

Even now, when altered circumstances make a high power gas an anything but desirable and economical supply, there are not wanting advocates who, undaunted or perhaps ignorant of the practical side of the question, still try to bolster up the old idea.

It was in the latter part of the eighties that the lot of the worried manager was made even harder by the rise in price taking place in

* Frankland's "Experimental Researches in Pure, Applied, and Physical Chemistry, 1877," p. 488.

cannel coal, on which up to that time he had entirely relied in admixture with ordinary gas coal to give those higher grades of illumination demanded by the fashion of the time, and which, although it ruined his coke, yet proved an efficient and reliable servant.

This increase in price became so serious that in 1889 the Gas Light and Coke Company commenced experiments which led to the introduction of carburetted water gas in place of cannel as an enricher, this process proving itself a most valuable addition to the manufacture of coal gas, and rapidly gaining favour and popularity not only as giving an easy means of raising the candle power of poor gas, but also as a standby in case of any sudden calls upon the production power of the works.

About this same period also another method of enrichment was introduced which consisted of adding to gas which did not fulfil the Parliamentary requirements the vapours of such highly volatile hydrocarbons as petroleum spirit and benzol, which on account of their high illuminating value gave the necessary increase in the candle power by the addition of an amount of vapour not likely afterwards to recondense from the gas.

Whilst these changes were taking place in gas manufacture rivals which seemed to threaten its very existence had forced their way to the front, and with the electric light largely used by the rich, and petroleum reduced to a price at which even the poorest could afford its use as an illuminant, the field of utility seemed to be rapidly disappearing from beneath the feet of the gas industry. However, when things were looking their blackest there slowly struggled into prominence and commercial success a factor which at once restored gas to its position of primary importance.

It was in 1885 that the researches of Dr. Auer von Welsbach culminated in the production of the incandescent mantle, which, frail and unsatisfactory in its earlier forms, was gradually so improved in composition and manufacture that by 1892 it became a brilliant commercial success, and placed in the hands of the gas industry a weapon which rendered their position unassailable in competition with electricity.

Looked at from a common-sense point of view, the incandescent mantle will be seen to be merely a method of enrichment. Instead of increasing the illuminating power of a flame by crowding into the gas more and more hydrocarbons, which during combustion are capable of separating carbon particles, the incandescence

In considering the value given to the gas by these burners, it is seen that, according to the method by which it is burnt, the consumer may obtain anything from 35 candles down to less than one candle per cubic foot of gas. It. must also be borne in mind that the burners employed in these tests were all good, wellmade burners, giving the best duty that can be obtained from them, whilst an examination of the burners used in consumers' houses shows that in most cases any antiquated and corroded burner is considered good enough at which to burn the gas, and the very people who are loudest in their complaints as to the quality of the gas are those who most disregard the method of its consumption.

Sir George Livesey, in 1900, pointed out that in fifty cases of complaining customers he had the old burners removed and replaced by new ones, when the complaints at once ceased, and on testing the burners so removed it was clear

that the trouble had been caused entirely by their condition being absolutely unfit for the consumption of illuminating gas. In another case, under my own observation, thirty flatflame burners were collected at random from houses of consumers supplied with the town gas. They were mostly union jet burners, Nos. 3 to 7, and were tested first when consuming 20-candle gas and subsequently with London gas.

With the 20-candle gas the best consumers' burners gave 14:08 candles per 5 cubic foot rate, and the worst gave 4.34 candles. Of the total number of burners 30 per cent. gave less than 7 candles per 5 cubic foot rate, and the average of the whole number made the illuminating value of the gas 8.5 candles.

With London gas, the best burner gave 10.6 candles per 5 cubic foot rate, and the worst 3.1 candles. Fifty-six per cent. of the total number gave less that 7 candles per 5 cubic foot rate.

The actual consumption of the burners when supplied with gas under 1 inches pressure varied from 4'5 to 5 cubic feet per hour, and the consumptions were the same with both kinds of gas.

England is far behind Germany in the use of incandescent lighting, and an inquiry made this spring into the uses to which the coal gas supply of a large town was put, gave the following result:

Incandescent lighting (private) 12.00 per cent.
(public). 6.25.

Cooking

Gas engines

Used in other ways

So that 47.5 per cent. is used for purposes in which illuminating power is of no use, and calorific effect is the one important factor.

It is also seen that 18:25 per cent. of the total gas made is used for incandescent lighting, and this represents about 23 per cent. of the gas used for illuminating purposes, as against 90 per cent. used in this way in Germany.

This 23 per cent. thus used gives for a consumption of 5 cubic feet not less than 70 candles, whilst the average light obtained by the combustion of the remaining 77 per cent. is 8.5 candles.

It is quite clear that under such conditions as these the supply of gas of a high candle power is simple waste of money, and it is manifestly unfair that the consumer of average

intelligence, who is willing to utilise the benefits given by the incandescent mantle, should have to pay for a quality of gas only rendered necessary by the inertia of those who decline to march with the times.

For many years, I have felt and pointed out that the consumer, knowing only that he wants more light, and absolutely ignorant of the principles of gas lighting, clamours for a richer gas, whilst the remedy is all the time in his own hands, and the only thing he has to do to attain his desire is to employ rational burners. Men like Sir George Livesey, Mr. Foulis, and Mr. Webber, have long since seen the fallacy of high candle power gas, and have fearlessly denounced it, and the time has now come when the principle is being widely grasped, and manufacturer and consumer alike are realising that cheap gas, and plenty of it, gives far greater possibilities and better illumination than high illuminating value gas which must of necessity cost more, as in trying to economise by using small burners, the lightgiving value is destroyed to such an extent that the effect produced is utterly inadequate to the cost.

The arguments brought forward in favour of high power gas, and its advantages over low grade gas, are, as they always have been, that for a given illumination it is cheaper, fouls the air of a room to a smaller extent, and does not for an equal illumination give as much heat. These contentions were to a great extent fallacious, even under the old conditions, as although a 22 candle cannel gas gives 4'4 candles per foot when burnt in a standard flatflame burner, as against the 3-2 yielded by the 16 candle gas burnt in the London argand, directly they came to be used under ordinary consumers' conditions there was little to choose between them, whilst any coign of vantage that cannel gas had entirely disappears under the conditions which now dominate the gas industry, and it is just Sir Edward Frankland's 96 feet of rubbish which makes the gas of the future.

Two years ago Mr. Webber gave a most interesting lecture before the Gas Institute, taking as a title "The New Gas," which turned out to be the low grade gas so widely used with incandescent mantles and for fuel purposes on the Continent, and pointed out that, freed from the trammels created by the Welsbach monopoly in this country, incandescent lighting in Germany had almost displaced all other forms of gas burning. There is not the least doubt that, with improvements and

cheapening in the production of mantles, the use of coal gas in this way would rapidly rise in this country to the same dimensions as on the Continent.

It will be well at this point to consider the conditions under which the gas manufacture at present labours, and the ground it must cover in the future, if it is to hold its own.

We have not heard so much of late of the working out of our coal supplies, but the fact remains that the best seams of gas coal are getting used up, and coal of this class will soon show an increase in price that will prevent any high quality of gas being made direct from it without a commensurate rise in the price of gas. All enriching materials, moreover, fluctuate in price with the demand made upon them, so that if the high illuminating value of coal-gas is to be maintained, the probabilities all point to a rise rather than a diminution in price; and even in calculating the probable saving to be obtained by the introduction of gas of lower illuminating power, this factor ought to be taken into consideration.

A 16-candle coal gas when consumed with the incandescent mantle may mean an 80 to 100 candle gas, and the difference with properly regulated air supply to the burners between a 16 and a 14 candle gas is so slight as to be undistinguishable to the eye, whilst the diminution in heating power which accompanies the lowering of the illuminating power, although not sufficient to make a large difference to the gas for fuel purposes, yet adds to one's comfort in a dwelling room, where as a rule the ventilation is none too good.

Coal gas is daily being used more and more as a fuel, and, although the slight diminution of calorific value which must of necessity accompany a lowered illuminating value is a slight drawback, yet in practice any desired temperature can be attained by a slightly larger consumption. Also a cheapening of the gas would induce many to adopt it as a fuel, this in turn tending to level up the load in production, and so render more economies possible. Everything clearly points in one direction, and that is that the future of coal gas is entirely dependent upon a plentiful supply of low grade gas-low grade from the point of view that it shall only have an illuminating value of 10 to 12 candles, that its heating value shall be as high as can be practically attained, and that its price shall be as low as is consistent with the interests of the consumers as well as of the shareholders in the gas industry.

Already the stream has set in in this direc

tion, and the lowering of the Parliamentary standard of 16 to 14 candle-power in the case of the South Metropolitan, and Commercial, and West Ham Gas Companies will soon be followed by many companies now saddled with a higher standard than 14 candles. That relief cannot be in fairness refused, whilst experience of the benefits conferred by the reduction will soon lead to the further step that will place gas manufacture in this country on the same advanced footing that already it has gained in the most progressive cities in Germany.

When, however, the change from a 16 or higher candle power down to a 14 or lower illuminating value has been sanctioned by Parliament, the gas manager finds himself confronted with the difficulty that his works have been erected and adapted for making the higher value, and all his practical knowledge is in that direction. His first trouble is to find out how this grave problem is to be overcome, and how the low grade gas can be most economically and best produced, and it is with the solution of this question that I now desire to deal.

In order to find an answer which will be of practical use it is no good advancing theories and proposing methods which necessitate such wholesale alterations in plant and procedure as would to all intents and purposes mean scrapping the existing generating machinery. The only processes which have a chance of being adopted must be very much on the lines of the old process, and if the plant be altered at all the alteration must be such as can be made at a reasonable outlay and without serious disturbance to the ordinary working. The gas which is produced must be in all save illuminating value of the same character as the coal gas, of which we know the behaviour, and for the consumption of which our stoves and burners have been constructed, special attention being paid to keeping up the calorific value and keeping down the cost.

The logical method of arriving at our result is first to see the composition which would yield ideal results, and then to see what process can be utilised in attaining the nearest approach to this. In order to do this, the first point is the effect of the constituents of gas on the results to be obtained from it.

The great advantages possessed by coal gas over the fuel gases properly so calledwater gas, Siemens's gas, and the hundred and one modifications of them which have been more or less used, consist in the presence