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of sound and practicable improve. impaired by the unavoidable alloy of ment, to the development of which smoky vapour. A separation, howa small portion of our time may be ever, may be effected by the distilling usefully devoted.
process, which leaves the
aërial As the subject has been involved fluid such as we have described. All in much confusion, and, to many of the new plans for lighting with coal our readers, must be altogether new, gas, proceed upon the principle of we shall first endeavour to state, in purifying this fluid, collecting it in a brief and popular way, the chymi- reservoirs, and distributing it in tubes. cal composition of coal, before we From the furnace where the coal is detail the new applications that are distilled, a main pipe may convey all proposed to be made of its ingredi- the evaporable matter into a large ents.
reservoir or gasometer, where, by Pit-coal exists in this island in various means, chiefly, we believe, strata, which, as far as concerns the by washing with water, it may be hundredth generation after us, may freed from impurities, and propabe pronounced inexhaustible; and is gated through the tubes in every so admirably adapted, both for do- direction by its own elasticity. If mestick purposes and the uses of the nothing confine it, it will issue from arts, that it is justly regarded as a the extremities in an equable flow, most essential constituent of our na. but still invisible, till a lighted taper tional wealth. When exposed to be applied, when it bursts into flame, heat, as we see it every day in our and continues to burn as long as the grates, it is manifestly composed of gas is supplied. Mr. Accum found, a fixed base of carbonaceous matter, by a comparison of shadows, in the and a variety of evaporable sub manner suggested by count Rum. stances, which are driven off in the ford, that the light of a gas flame is form of smoke and flame. But, in to that of an equal-sized flame of a stead of being consumed in this open candle or lamp as 3 to 1;* or, in way, the coal may be distilled, and other words, that to light up a certhese evaporable matters collected in tain space, one gas flame will give proper vessels, and examined. They as much light as three candles burnare then found to contain, besides a ing with a flame of equal size. The considerable quantity of matter, which products of the combustion are in is condensed by cold into tar and al. both cases the same-water and carkaline liquor, an invisible elastick bonick acid gas; but with this matefluid, or gas, which no cold nor effu. sion of water can condense or absorb. jets; and the gaseous oxide is occasionally It is a compound of two highly in seen near the root of the flame, or in con. flammable gases, which chymists call
tact with the coal. It is possible that a the light hydrocarbonate, and the
small portion of this oxide may mix with
prepared gas. heavy hydrocarbonate, or olefiant gas; and this mixture burns with a very
* We should have suspected the pro. brilliant and beautiful light. It is this portion was overrated, had not the same gas which furnishes the flame in our
accurate experimenters assured us, “that
500 cubick inches of gas, burnt from the common fires;* but its beauty is there orifice of a jet, so as to produce a flame
equal in size to that of an ordinary can. * There are, in fact, according to Mr. dle, consumed 1076 cubick inches of oxyDavy, three inflammable gases given out gene gas in the same time that a candle in our fires—the two we have mentioned, kept burning in the best possible manner, and the gaseous oxide of carbon, which consumed only 279. And we know, that is known by its blue flame. They are all the intensity of any artificial light depends distinctly perceptible. The light hydro- on the rapidity with which oxygene is abcarbonate forms the main body of the sorbed.See Appendix to Report of the fame; the olefiant appears in brilliant Committee, &c.
rial difference, that candles Frequent " the whole of the rooms of this, the ly, and lamps always, give out a most extensive cotton mill in the quantity of smoke and soot; whereas kingdom, with the counting house the combustion of the gas is perfect, and store-room, and the adjacent and leaves no sensible residuum dwelling house of Mr. Lee, are now, nothing that can soil the most deli- and have been for several years, lightcate white. Its effects on the air of ed up with the gas from coal, to the a room are, therefore, less insalubri. exclusion of all other artificial light." ous than those of a candle, since the The manner in which the gas is proonly noxious substance it yields is cured and distributed, we shall quote carbonick acid gas; and this it pro- in his own words. duces in smaller quantity than our “ The coal is distilled in large iron re. common lights. From the inflamma- torts, which, during the winter are kept ble properties of the gas, explosions, constantly at work, except during the inbursting of tubes, and other dangers tervals of charging: and the gas, as it might be apprehended. But there is pipes into large reservoirs or gasometers,
arises from them, is conveyed by iron no ground for such fears. On the
where it is washed and purified, previous contrary, nothing can be more sim
to its being conveyed through other ple or easy in the management The pipes, called mains, to the mill. These gas may be confined by a stop-cock mains branch off into a variety of ramifiwith perfect safety, and issued as
cations, forming a length of several miles,
and diminish in size as the quantity of gas occasion requires. When it is ex
to be passed through them becomes less. hausted, the flame goes out as quiet. The burners, where the gas is consumed, ly as the fame of a candle does, when are connected with the above mains by the tallow is spent.
short tubes, each of which is furnished Such are the nature and properties
with a cock, to regulate the admission of of this curious and beautiful sub.
gas to each burner, and to shut it totally
off when requisite. This latter operation stance, when examined in a small
may likewise be instantaneously performed way in the laboratory of the chymist. throughout the whole of the burners in each But it frequently happens, that theo- room, by turning a cock, with which each ries perfortly just and elegant in
main is provided, near its entrance into the
room.” themselves, and confirmed by expe. ments on a small scale, with a nice
By a comparison of shadows, the apparatus and skilful management,
whole light of the gas flames used are yet, when attempted in the large dles of 6 to the lib. We cannot en.
was found equal to that of 2500 canand wholesale way, utterly incapable ter into all the items of expense : of being reduced to practice; and thus, many a promising plan has they are given with the most scrupu. ended with performing nothing. But,
lous accuracy; and the economical in the case before us, there are facts, The cost of the cannel coal which he
statement for one year stands thus. of the description we want, to be col. lected from different quarters, and
used to furnish the gas, is 251. furnished by individuals unconnected
and of common coal to carbonize it, with each other, which fully verify duct the value of the coke, 93. and
201. in all, 1451. from which dethe anticipations of theory, and the conclusions of more limited experi
the whole expense in coal is reduced
to 521. The interest of capital sunk in ment. The first, and by far the most va ·
the apparatus, with a liberal allow. luable of these facts, is contained in
ance for tear and wear, is stated at Mr. Murdoch's paper; the chief ob
5501, making the total expense of ject of which is to describe the mode lighting the manufactory about 6001, of lighting the cotton-mill of Messrs. a year. That of candles, to give the Philips and Lee, at Manchester.
* Vide Nicholson's Philosophical JourFrom this account we learn, that nal for October laste
same light, would be about 20001. cast iron cover,' which I lute to it with If the comparison were made on the sand. Into this pot I put my coal. I average of three hours a day, which, pass the gas through water into the gasoin most cases, would perhaps be
meter or reservoir, which holds about
400 gallons; and, by means of old gun nearer the truth, the advantage would barrels, convey it all round my shops. be still more in favour of the gas Now, from twenty or twenty-five pounds lights. The interest of capital and of coal, ! make, perhaps, six hundred tear and wear, remaining nearly the gallons of gas ; for, when my reservoir is same as in the former case, the whole full
, we are forced to burn away the over
plus in waste, unless we have work to cost would not exceed 6501, while
use it as it is made : but, in general, we that of the tallow would be 30001.
go on making and using it, so that I canHere, then, we have a saving of not tell to fifty or a hundred gallons. And, three parts in four; and it is not in fact, a great deal depends on the coal, likely, as we shall see hereafter, that
some coals making much more than others. Mr. Murdoch has reached the ut
These twenty-five pounds of coal put into
the retort, and say twenty-five pounds most point, either of economy in his
more to heat the retort, which is more process of distillation, or of simpli- than it does take one time with another city in the
construction of his appara--but I am willing to say the utmost, are tus. “ The peculiar softness and worth four pence per day. From this clearness of this light,” says Mr. four pence we burn eighteen or twenty Murdoch, under whose direction the lights during the winter season.”
In this manner are the candles whole was completed, “ with its almost unvarying intensity, have
which he used to employ, and which brought it into great favour with the
cost him three shillings a day, entirework people: and its being free from ly superseded. But, besides his exthe inconvenience resulting from the pense in candles, oil and cotton for sparks, and frequent snuffing of the soldering used to cost him full 301. a candles, is a circumstance of mate- year, which is entirely saved, as he
now does all this soldering by the gas rial importance, as tending to diminish the hazard of fire, to which
flame only. For “ in all trades in cotton mills are known to be much
which the blowpipe is used with oil exposed.”
and cotton, the gas flame will be The next fact we shall bring for
found much superiour, both as to ward is important, inasmuch as it The flame is sharper, and is constant
quickness and neatness in the work. shows, that the superiority of gas ly ready for use ; while, with oil and lights is not confined to great manufactories, but is equally apparent in
cotton, the workman is always forced those on a small scale ; thus opening is, till it is sufficiently on fire to do
to wait for his lamp getting up; that a much wider range for the possible his work. Thus, a great quantity of application of the new mode. We are indebted for this fact to a Mr. but, with the gas, the moment the
oil is always burned away useless; Cook,* a manufacturer of metal toys stopcock is turned, the lamp is ready, at Birmingham; a clear headed, prac. and not a moment is lost.” We must tical man, not apt to be dazzled by a fanciful theory, but governed in his refer to Mr. Cook's letter, for the transactions by a simple balance of details of expense, which he gives
with faithful minuteness, and always profit and loss. There is a naïveté in his own account of this process, the gas. The result of the whole is,
leaning to the side unfavourable to which will amuse as well as instruct that he saves 301. out of the 501. which the reader.
his lights formerly cost him. And, “ My apparatus is simply a small cast when
we consider that his calculation iron pot, of about eight gallons, with a
allows the gas lights to be burnt the Philosophical Journal for December whole year, and the candles only 1808
twenty weeks, there can be little
doubt, that the savings in this case ing his support to the measure. Since follow nearly the same proportion as that time, a general meeting, it seems, in the former. If the apparatus be has resolved not to regard the answer erected on a still smaller scale, “the of Mr. Perceval as a final rejection, saving,” Mr. Cook assures us, “ will but to come forward with their claims be equally great: for the poor man for a charter, during the present ses. who lights only six candles, or uses sion. On what grounds these claims one lamp, if the apparatus is put up are founded, it is not very easy to in the cheapest way, will find it only discover. It is possible that governcost him 101. or 12l. which he will ment, foreseeing that the new mode nearly, if not quite, save the first of lighting would render less producyear.'
tive the taxes raised on the common The last trial of gas lights we shall materials, might think it wise to sancmention, though not the most satis- tion some publick establishment, by factory, has made the greatest noise way of securing to itself a share in in the world, and was, indeed, what the profits. But it is the title of Mr. first led us to think upon the subject. Winsor and his friends to an excluDuring one of those excursions to sive privilege, that puzzles us. We the metropolis, with which we occa- attempted to look for it in his pam. sionally treat ourselves, after a long phlets; but encountered, at every period of northern rustication, our step, such ignorance, quackery, exatte. tion, at such a time alive to eve- travagance, and false calculation, that ry thing, was arrested by a new and we had scarcely patience to wade singular spectacle. The whole range through them. As, however, we are of Pall Mall, from St. James's to in search of facts, we shall, in merCockspur street, was lighted up by cy to a foreigner and an enthusiast, means of lamps, fed with gas instead who talks about his new light with all of cotton and oil, and certainly in a the ferver of a fanatick, pass over style of much superiour brilliancy. his wild reasonings in bad English, We found, upon inquiry, that the and state briefly whatever there is of conductor of this remarkable illumi. value in his plans and processes. nation was a Mr. Winsor, acting un We must premise, however, that der the auspices of a committee of we cannot allow him the credit af subscribers ; and that it was execu- being a great discoverer-a name ted by them as a grand experiment which he is suspiciously fond of to convince parliament and the pub- arrogating to himself. That coal lick of the national importance of yields an inflammable gas has been their intended Light and Heat Com- long known; and its nature is partipany. Subscriptions had been col- cularly described by Dr. Clayton in lected, to a very large amount, to the Philosophical Transactions for carry into effect Winsor's discovery; 1735. With regard to the useful and 20,0001, vested in a committee, application of it, Mr. Murdoch was to assist him in his experiments, and undoubtedly the first who conceived make application to parliament for a the idea of conveying it through charter of incorporation. In prose- tubes, and employing it for artificial cution of these objects, we afterwards light; and we embrace, with plealearned, that a correspondence was sure, this opportunity of doing jusopened with the chancellor of the ex tice to the modest fame of our counchequer in the month of March last; tryman. This was as early as the but he, alleging partly the advanced year 1792, long prior to the period state of the session, which did not al. from which Winsor himself dates low a private bill to be presented, his discovery. We fear, therefore, and partly his own doubts as to the that the bugbear of his patent right, utility of its object, declined promis- which he holds out in terrorem, widi
avail him little, and that it is impos- riority of coke. ♡ I have learned," sible to give him or his friends the says Mr. Accum,* “that the heat promonopoly of a practice, which is al- duced by coke, when compared with ready adopted by several persons who that which can be obtained from coal, pretend to no secret or mystery in is at least as 3 to 2.” Thus he found, the art. We cannot discover that there that it required three bushels of coal is any decided superiority in Mr. to distil a given quantity of water, Winsor's gas lights over those of Mr. and only two of coke. He tried the Murdoch. It is asserted, indeed, in two substances also by combustion, “Considerations,” &c. that it is neces- with a certain measure of oxygen gas, sary to take to pieces, now and then, by the fusion and the reduction of the tubes in Mr. Lee's manufactory, metals, &c. and the same result was to clear them from impurities; while obtained ; a result certainly not unthose of Mr. Winsor contract no soil important; since it proves that, by by any length of use. But Mr. Mur- being forced to yield the material of doch expressly assures us, in his pa a beautiful light, coal is actually imper, that all inconveniences of this proved very considerably in its power kind are now entirely done away of giving heat. We have not the Winsor's Analysis of New Castle least doubt that this coke, as Winsor Coal is certainly very complete. The produces it, and as we have seen it gas flames he exhibits in the different used in his house, might be introapartments of his house are extreme duced to form, if not the whole, at ly brilliant; and the variety and neat least four fifths of our common fires, ness of their application worthy of with a very great addition of comfort, praise.
cleanliness and economy. Let it be He deserves credit too, we think, observed, however, that we possess for calling the publick attention, more no facts that warrant us in pushing than had been done before, to the pe- this conclusion any further than re. culiar advantage of coke as a cheap gards the coke of Newcastle coal. and agreeable fuel. This substance Mr. Murdoch, though he makes prois the residuum that is found after per allowance for the coke produced all the evaporable matter has been in his process, does not enlarge at all expelled from the coal by heat. It on its qualities ; and it is probable, comes out from the distilling process that some species of coal generate in large, spongy masses, greatly dimi- coke too dull and difficult of ignition nished in weight, but increased in for consumption in our grates, and bulk nearly one third. Though some only fit to be used in stoves and what more difficult of ignition than furnaces where there is a strong coal, it burns longer, and gives out draught. But we are persuaded, that a steadier and more intense heat. the greater proportion of the other That it should do so, will not appear varieties in the island will be found, strange to our chymical readers (and on trial, to yield the same sort of who is there now that does not know coke as Winsor's, and that it can something of chymistry ?) when it is never be produced in such quantity, considered that the quantity of mat- by the extended use of the gas lights ter, which, in the combustion of coal, hereafter, that the demand will not is changed from a solid-to a state of fully and rapidly absorb it. Its meelastick fluidity, must necessarily car- rits have long been acknowledged ry off much calorick in a latent state; in many processes of art; and it is while the glow of the coke radiates prepared from coal with the loss of with an intensity unimpaired by any all the volatile ingredients in the great demand of this kind. The same re- manufacturing districts; and if the spectable chymist we formerly mentioned, bears testimony to the supe: Appendix to Report of the Committee.