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Ystalyfera cold-blast-average deflection
Deflection of cold-blast iron from Mr. Fairbairn's table.

lbs. 1.916

1.612

Difference in favour of Ystalyfera iron

lbs. 304 --equal to 18 8-tenth per cent. Ystalyfera cold-blast iron, in respect to its resisting impact, general average of five feet bars ...

lbs. 1235 Hot-blast iron from Mr. Fairbairn's table....

690

lbs. 545

Difference in favour of the Ystalyfera iron ...
-equal to 79 per cent.
Ystalyfera cold-blast iron, in respect to its capacity to resist impact..
Cold-blast iron from Mr. Fairbairn's table

lbs. 1235

734

Difference in favour of the Ystalyfera iron 6....... lbs. 501 -equal to 68 2-10th per cent.

From these, and the former comparative ness, or elasticity, which communicates a experiments, it is abundantly evident that tendency to the bar, in deflecting and breakthe pig-iron, now making with cold-blast ing, to resume its rectangular form. Bars and anthracite, at the Ystalyfera Iron Works, that had obtained a permanent set of 2-10ths, greatly exceeds, in strength and deflective when afterwards broken, presented but a powers, and capacity to resist impact, any slight deviation from a right line ; and in no iron at this time manufactured in the United case did the acquired curvature exceed oneKingdom. It now only remains for me to fourth of a tenth. It was also remarked, mention a property peculiar to the iron, that most of the fractures, in breaking, prewhich was noticed at the time I made the sented a regularity of grain throughout, trial experiments at Yniscedwyn, four years resembling the structure of unhardened ago, but which has been more fully developed steel. in those recently made at Ystalyfera. The

David MUSHET, property referred to is one of great springi Coleford, Nov. 18.

BLAXLAND'S PROPELLER. Sir,-It was only this day I learnt from a Reach the Novelty came alongside the friend that Mr. Elijah Galloway, C.E., in a Swiftsure for a few seconds, but there fallwork on " the Archimedean screw and other ing far astern, for the fifth or sixth time, she submarine propellers,”—(we shall some day, tacked about the distance from the Reach to I presume, have a numismatic writer publish Greenwich, being too little for another shoot. ing an account, in imperial quarto, of the The Swiftsure, during this last run, was sixpence, or the silver penny)—has been compelled to slacken once, for full ten mi. pleased to say, the shades of Mendez Pinto, nutes, that the tightening-screws of her and of the Lord of Campoli, hovering over ropes might be put on, and no more than and directing his pen--that the screw-pro 32 of her 40 horses' power, (low pressure,) pelled "steam-ship," on a certain occasion, owing to the newness of the ropes, could, on ran with the Swiftsure, and ran round her. an average, be employed.

The truth is as follows. On the 6th of The tide against the vessels, on their reJune, the Swiftsure quitted her moorings at turn, was taken at two miles; but the Greenwich, and went down the river, for the steam-ship” being fully rigged, it was purpose of adjusting her new ropes. As she considered the strong wind in favour bapassed Blackwall, the said “steam-ship,” lanced her account with it. The singular called, I believe, the Novelty, (why not irregularity of her speed—evidencing that “Wimshurst's Folly ?") then lying there many times her feed-pumps were shut off, with her steam up, started for the purpose, for the purpose of keeping her steam in ber as was afterwards seen, of running with her. boiler--was remarked, as was the extreme Upon the Swiftsure's reaching Erith, she blue of her exhaust steam, denoting the turned, and met the Novelty worming her enormous pressure upon it. Her mode of way by Half-way Reach. The latter turned steaming resembled much the progress of about, and from thence, as far as Blackwall the Gyrinus (water tlea). Reach, endeavoured to overhaul her, till What the speed of the Novelty may be, then, unconscious antagonist.Huc magno (74 miles in her advertisement for sale,) and cursu contenderunt," and at Blackwall what the speed of the Swiftsure, we are not

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here called upon to inquire. The relative ceive between the combustion at the front of speeds of the Archimedean screw and of Mr. the grate and at the back, I referred to Blaxland's propeller—the target fired at want of air, and with reason I am inclined are at this very time being tried by Govern. to think, as the supply of air in the latter ment.

situation is far inferior to that in the former,
Such are the facts—Perspecta et explo and the heat in both must be nearly alike.
rata sunt, quæ
scribo."

Your correspondent, however, contends
Yours, &c., (apparently, for he does not express himself

C. very clearly) that this is owing to want of
P.S.-It may not be quite uninteresting heat, and I can assure him I have no wish
to your readers to be informed that the Little to disturb his opinion, or commence a dis-
Jane, whose extraordinary performances you pute on such a trivial subject, it being, be-
have recorded, has been now some time in sides, one upon which it were impossible to
the service. She is the pinnace to the Sala arrive at anything like demonstration ; of
mander, from off which frigate she is destined course he would greatly respect a mathema.
to land the British Ambassador, the Right tical proof.
Hon. Henry Ellis, at Rid.

My recommendation, that the back of the
November 28, 1842.

grate should be assimilated somewhat to the
front, so as to admit air, is construed by
your correspondent into a detailed sugges-
tion on my part, that it should be "

perDOMESTIC FIRES AND KING'S STOVE GRATE.

forated with holes;" this plan, though rather Sir,-Your correspondent, “ T. H. B.,' in a crude state, I am, however, willing to (with whose style I somehow fancy myself ac adopt as far preferable to the corrugated quainted, although I do not remember his sig back, whose virtues are lauded by your cornature,) seems (p. 494) to have been so very respondent. I cannot, however, subscribe anxious to dispute the few remarks upon to the supposition that it is useless, (with combustion which I took the liberty of send regard to its heat-giving power) to have the ing you, and to which you were kind enough back of the fire as brilliant as the front, still to afford a place in your columns, that he less to the original idea, that "at the same almost forgot to ascertain what the remarks expense, more heat will be obtained by keep. themselves were, and to what they applied : ing a large fire, right in front, but black how far he apprehended their object appears behind ;' both which rest on the erroneous from his assertion, that I complain that, notion, that the heat thrown out by a fire from the escape of unconsumed gas in com depends upon the heat in the front merely, mon grates, “ heat is lost;' my remarks and not upon the actual quantity of heat in having had regard altogether to the preven the whole fire, the latter being the real tion of smoke, without at all referring to the source from which to estimate the heating loss of heat, or any means of saving it. I effect; for we find that the beat thrown out may now add, that I consider the latter an by a furnace through its door, depends as insignificant desideratum, when compared much upon the size and heat of the furnace, with the former ; in reference, of course, to as upon the size of the door. Moreover, the the consumption of fuel in a large city. heat transmitted to the wall cannot be con

The importance of this subject is well sidered as lost, any more than the power contended for in the extract from Mr. Cur

transmitted by any kind of machinery, for it tis's work on “ The Preservation of Health,' all comes into play again, being diffused which appeared in the same Number of your through the wall, and in this manner exMagazine as your correspondent's letter : pended in warming the rooms at each side. and undoubtedly, the recommended general Your correspondent's plan for a stoveadoption of Mr. Williams's“ argand furnace" grate will be considered, I should expect, too in all London manufactories would greatly unseemly an excrescence in a room to be abate the smoke nuisance, but I fear that generally adopted; although, perhaps, it may we can scarcely expect thus to remove it en be a medium between the stove method of tirely ; for it must be allowed that the warming a room, by communication and enormous quantity of smoke generated in heating the air in it, and the more pecuthe innumerable domestic hearths through- liarly English method, radiation; which, out “the great Metropolis,” would be of permitting us while comfortably warm to itself sufficient to constitute a very injurious enjoy a comparatively cold and fresh atmodegree of impurity in the atmosphere, as sphere, seems too firmly fixed in use in this well as a very visible fog. This considera country to be easily changed,-an Englishtion it was that suggested the remarks in man at once perceiving an unpleasant closequestion.

ness in a room warmed by a stove, (without The difference which we sometimes per much draught), even though it be kept at

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only a moderate heat, as those of the Arnot tribe usually are. I am, Sir, your obedient servant,

R. W. T. Postscript. Sir,--Perhaps you will permit me to add a postscript to my letter already forwarded, as I have just seen the account of Mr. King's stove in your last Number (No. 1009).

The introduction of this subject seems to have produced a combustion among the stove-loving part of your readers. I hope that it may not, like the imperfect one de. precated, end in smoke.

I can easily believe that Mr. King's stove carries out my view, more than J. H. B.'s does; but it does not come up to my beau ideal of an anti-smoke grate, and differs very considerably from one I was about planning a short time ago, but which I have not had leisure to finish, as the details require much consideration, as well as experimental examination of the subject. This, however, is a case in which nearly the same end may possibly be arrived at by apparently differing means. And, besides, it is very little matter whether my suggestions are carried out or not in Mr. King's stove, if it is a good consumer. I am sure his conductor would be an excellent addition to most grates, and probably go far to cure a smoking chimuey, although it might, perhaps, sometimes be the means of originating a puff.

I am, Sir,
Your obedient servant,

R. W. T.

was applied, has been found in use to realize all the advantages ever claimed for the semi-rotative class, without entailing any of their numerous defects. A description of this engine was published in your 31st volume, page 210, and an engine of this de. scription has been in daily use for the last four years at the patentee's works at Dept. ford, where it may be seen in operation by any person who feels an interest in the matter.

The “Cambrian Oscillating Engine," described at the commencement of the present volume, in its action bears a striking resemblance to Bunnett's concentric engine, but a comparison of the two will show that there is a wide and important difference between them,

I am, Sir,
Yours respectfully,

Wu. BADDELEY,

ADDELEY. 29, Alfred-street, Islington.

December 7, 1842.

RAILWAY REFORM.

DOUBLE REVOLUTION STEAM-ENGINES

BUNNETT'S CONCENTRIC ENGINE. Sir,— Your correspondent, Mr. Thomas Rolls, who sends you a sketch of a " Double Revolution High Pressure Steam-engine,” (described at page 514,) states that he considers it “perfectly new," and to him I have no doubt it is so.

I think it right, however, to state that the “ double revolution” part of the affair, forms one of the “ Improvements in Steam-engines,” for which letters patent were granted to“ Joseph Bunnett, of Deptford, Engineer,” in June 1838! Mr. Rolls must be content therefore, to forego the "obvious advantages' of his invention, though what he supposes these advantages to be, is not stated. His vibratory engine consists of an arrangement that has been invented, re-invented, and patented some score of times, but has never yet been found to realize in practice any very “obvious advantages.

Bunnett's Concentric Steam-engine, to which the " Double Revolution" movement

Some more killing and breaking of bones, and, as the customary sequel, a little more reform. It would almost seem as if the Companies habitually resisted to the killing point all improvement, in order that they may have the adoption of some universally called for alteration of system, to set off against each fatal accident as it occurs—to reconcile the public, as it were, to the disaster of the moment, by the reflection that it has brought about a change which will make railway travelling all the safer for the future.

The accident to which our attention is at present called, is one on the Birmingham line, by which one person has been killed, and three others seriously wounded. was caused by the overturn of the engine, through the breaking of the front axle, and that engine a FOUR-wheeled one, with inside bearings—the very sort of carriage which the Birmingham Company, its officers, and its engine builders, have of late been striving so hard to persuade the public is incapa. ble of being overset from any such cause – so much so, that it could run almost as well with an axle sawn through, as entire.

Mr. Parker, the foreman of Messrs. Bary, Curtis and Kennedy, the engine builders to the Company, in his evidence at the coro

ner

ner's inquest on the body of the person killed, either way, and never once (we believe) any asserted that the accident would have equally carriage stationed farther to the rear. Often occurred if the engine had been one with and often have the railway companies been six, wheels. He cannot seriously expect urged to adopt this obvious plan of protecthe public to believe this. He must have tion; but, until just now, with only very meant what he said with a reservation ; such partial success. When crowned heads have as, that the six-wheeled engines he referred had occasion to travel by railway, the plan to were those of the old and still common has been invariably adopted (killing a soveform, with outside bearings. He certainly reign being, it would seem, more than they could not mean to say, that the risk of over chose to run the risk of); but the vulgar setting would not have been greatly dimin million most of the companies have persisted ished if the engine had been on sir wheels, in carrying as before, in close proximity to with inside bearings, on the same judicious the engine. At length the melancholy acciplan on which the four-wheeled engines dent which has called for these present remade by his firm are constructed, and for marks occurs, and Mr. Bury, in giving the first introduction of which they deserve evidence respecting it before the coroner, all the credit which they claim. (See Cir is obliged to make this explicit admissioncular of Messrs. Bury, Curtis, and Kennedy, An empty carriage or van, interposed in Mechanics' Magazine, No. 1006, and

between the engine and carriages, in this also the letter from the firm, in our present

instance would have prevented the accident,"

(i. e. the death of the person killed.) Number.) Our own firm belief is, that,

Mr. Bury is naturally asked by the corohad the engine been one of this description, there would have been no oversetting, and

“Admitting then, as you of course do, no damage from that cause, at least.

its safety, why do you not adopt this plan? But there is another danger, besides over Are there any objections to it?" setting, likely to result from the breaking And he answers of an axle. The sudden stoppage of the

“ There are objections to it. The engine of a train going at the rate of between

matter has been a subject of great discussion, 25 and 30 miles an hour, (the rate at which and I believe the company will now adopt the one in question was going,) is certain,

the plan. Experience points out the necesif it remain on the line, to cause a crushing

sity of doing something of the sort; yet there

may be circumstances in which a truck or collision between it and the first carriage van, placed between the engine and carriages, behind (and perhaps second) so as to make would produce serious accidents.” the latter swerve from the line, at the risk, What “ circumstances ?" We have heard in some cases, of being dashed against an before of such “ circumstances,” but always adjacent wall of rock or earth, or, in others,

in so vague and mysterious a way, that we of being thrown over a high embankment; never could make any thing tangible of and, as regards this sort of accident, it them. We cannot, ourselves, imagine any matters nothing whether the engine is on class of circumstances whatever, and do not four wheels or on six. An absolute remedy believe that any such can ever exist, under for it there may be some difficulty to find; which any serious accident could possibly but all mortal harm from it can always be arise from the interposition of a luggage averted by carrying nothing in the first and van or two between the engine and passenger second carriages next to the engine but carriages-that is, accidents involving loss goods or luggage. Many accidents have

of life or personal injury, of which alone happened, as well from such direct collisions, we speak, and about which alone the pubas from engines turning over to one side, to lic have any anxiety. the first carriages of trains, and many have The jury found a verdict of “ Accidental been the lives destroyed by them ; but very death," with a deodand of only 58. on the rarely has a second carriage been injured in engine ; but accompanied their verdict by a

recommendation to the railway company, secutions, decided that M. Jules Bourgeois, " to place for the future an empty carriage,

Administrateur délégué; M. Bordet, Proor luggage van, between the engine and

visional Director; M. Henri, Chief of the

Paris Station ; M. Bricogne, Civil Engineer, the passenger carriages.” Whereupon, Mr.

Directeur du Matériel ; M. Lamoninare, Chief Creed, the secretary to the company, an of the Station at Versailles ; and M. Milhau, nounced that " The company had already Inspector of the Service, should be arraigned determined upon adopting the plan suggested

as guilty of homicide through imprudence.

The act of accusation, or indictment, gare by the jury.

a full and minute recapitulation of all the And this, gentle reader, is the little more disastrous circumstances attending the accireform which we spoke of in the outset as dent, enumerating the persons who became being the consolatory result of the little

its victims, either by loss of life or severe

mutilation. The points of accusation inmore killing and bone-smashing.

sisted upon by the prosecution were—the The four-wheel system, which was the insufficiency of the number of engines for primary cause of the accident, is still, for the service of the road, so as not to allow some time longer, to be adhered to on the

time enough between their respective jour.

neys to be properly inspected and repaired, Birmingham line, in spite of the many

when requiring repair ; the unfitness of the proofs which experience has furnished of

four-wheel engine, the Matthew Murray; its tendency to produce such accidents, and the want of judgment and prudence in in spite of public opinion, often and most

placing it before the Eclair, a six-wheel

engine of much greater force; and, lastly, unequivocally expressed, on the subject;

the imprudence of running the train with too but the dangers attending it are to be hence

great velocity, whereby the accident Fai forth so far diminished, that when axles caused. On the question of the fitness of next break, and engines next tumble over

the Matthew Murray, the testimony was

various and contradictory. It certainly apembankments, there shall be one luggage

peared from the evidence that its peculiarities van, at least, between them and the pas

required a skilful conductor, but it was desengers. Two would be better ; but that clared, that with such conductor it was an would have been too much to hope for at

effective machine. On the subject of the

opinion of George, who guided it on the 8th once, at the hands of such slow-going, bit

of May, and who was among those who lost by-bit reformers. Let us be thankful that

their lives on that day, who also is acknowone step has been gained, as long as it is ledged by every one to have been both skilful one so much in the right direction. We

and zealous in the service, the evidence was very

contradictory. Some witnesses deposed that have but to wait for a few more such inno

he had frequently denounced itas incompetent cent illustrations as we have just had of the and dangerous, and others declared that it was infallibility of the four-wheel system, and a favourite with him, and that he took great we may safely reckon on that, too, being

pride and pleasure in guiding it. The charge

of want of skill and judgment in placing the ultimately classed among the exploded errors

weaker engine before the more powerful one of a bygone time.

was rebutted. This was proved by men of experience to be the universal practice, and the suggestion that the strongest engine must

overrun the weakest was shown to be false THE ACCIDENT ON THE VERSAILLES RAIL

and unfounded, as the swiftness did not de WAY-ACTION FOR DAMAGES.

pend upon power of traction; and further, The important trial arising out of the that if the stronger machine, by drawing with awful railway accident of the 8th of May greater force, took the weight of the train, last, and which, in fact, is a grand inquest the weaker, by being thus reliered, would go taken on the causes and consequences of this the faster, and thus keep out of the way of lamentable event, commenced on the 22nd the other, and could not be overtaken by it. Nov., and was continued de die in diem until The last charge, that of the train being arged Dec. 3. The Chamber de Conseil having, to an inordinate degree of velocity, was, after mature consideration of the previous like the others, a subject of strongly conflictexaminations, declared that there were no ing opinions. Many witnesses, as well from grounds for including the Council of Ad. among the persons who were passengers as ministration of the Company of the Paris and from others who observed it from the road. Versailles Railroad (Left Bank) in the pro side when passing Sevres and Meudon, im

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