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About a twelvemonth ago the same engineer proceed from this cause, and that I can also point erected for the Brighton Railway Company a out the source from which it really arises. steam engine air pump, and two pneumatic cranes If friction were the cause, there ought to be the at the London-bridge goods station. These were same amount of heat developed whenever air used nightly from that time until the opening of the moves at equal velocities through similar aper. Bricklayers'-Arms station, in May last, and as yet tures. So far from this being the case, the pneuhave not been removed. The order was for" six matic engine that admits the air into the exhausted pneumatic cranes of two tons power each, and a pipes is always intensely cold, while the pump 6-horse engine and air pump to work them." In which is drawing the air from the same pipes is as consequence of the warehouse having been erect- constantly intensely hot. As the passages of the ed of a less size than was originally designed, only pneumatic engines are usually far smaller than

two cranes were made, but the engine and pump were constructed as at first ordered. Though the price paid was only for 6-horse power, yet the cylinder was made twelve inches diameter and two feet stroke. This, for a high pressure engine, with no more expansion than could be obtained in the slide! I will leave it to your mechanical

those of the pump, the air must rush through them at a greater speed; and therefore a larger amount of heat than that at the pump ought ght to be developed at the engines instead of the intense cold which is invariably experienced. I have had engineers remark to me, when standing by an air pump at work, that this heat must be caused by the friction

readers to form an estimate of its real power, of the piston; upon which I have propped up the which is certainly nearer 12 than 6-horse. Not- delivery valve, so that the pump merely drew in withstanding this enormous cylinder, and its only and delivered at it in the same manner as a comdriving two cranes instead of six, it had its mon syringe. After working a few strokes thus, work to do, and I have little hesitation in saying the pump always cooled down. Now as its pis

that four or five cranes would have been the limit of its power. About this time Mr. Hague was ordered by the Admiralty to attach an air pump, requiring 8-horse power to work it, to the factory engine at Woolwich dockyard, the above 8-horse being surplus power which was to be applied by pneumatic engines to some of the machines in the old work shops, and to the greater part, if not the whole, of those to be erected in the new buildings. The air pump and two engines have been fixed in the old part of the factory, and nine others

are

ready for the new. A trial, and I believe a successful one, has been made of those which are erected; but I think it will be found that though the air pump will most certainly require 8-horse power to work it, yet that 4 or 5-horse is the utmost which will be obtained from the engines.

As a further proof of the loss accruing from conveying power by the rarefaction of air, let us suppose the following simple case. Let it be required to raise two equal weights-say 10lbs. through the same space-say one foot; and ima gine one weight to be provided with a spring between it and the ring by which it is raised of such an elasticity as to expand one foot with its 10lbs.; and the other weight to be of the ordinary construction. In the first case we must exert a gradually-increasing force (from 0 to 10lbs.) through one foot, before the spring is capable of moving its weight; and then we must exert an uniform force of 10lbs. for the foot through which we have to raise it; so that the whole power required will equal 5lbs. (the mean between 9 and 10) though one foot added to 10lbs. through the same distance equals 15lbs. exerted through one foot. In the second case we shall clearly only use a force equal to the work done, namely, 10lbs. raised one foot. Therefore, by the employment of a spring (representing the air) between the power and the work to be done, we incur, in this case, a loss equal to one-third of the whole force exerted.

Much has lately been written relative to the heat developed in the air pump; and by some, and among others by a writer whose opinion was quoted in the Times' of the 27th of June last, this heat has been attributed to the friction of the particles of air. I think I can show it does not

ton was moving at the same rate as before, and there was positively more air rushing through the aperture, the friction of the particles must have been greater, and that of the piston the same; so that the heat ought to have increased had either friction theory been correct.

The true cause of the phenomenon is simply this: when air is expanded, like all other bodies, its capacity for caloric is increased; when, therefore, a portion of the atmosphere rushes through a pneumatic engine into an exhausted pipe, and is expanded to double or treble its bulk, it has a greater power of absorbing heat. This required heat it can only procure from the sides of the vessel in which it is enclosed. Not being able to obtain it with sufficient rapidity by this means, its own heat has to be divided among the increased volume; and in this way a sensation of extreme cold is produced, analogous to that experienced by placing either on the skin, or to that produced in the operation by which carbonic acid gas has been solidified. This, then, accounts for the cold at the point where the air is admitted. If the hand be passed along the pipes leading from the pneumatic engine to the exhausting pump, they will be found to become warmer and warmer until (if of sufficient length) they will arrive at the same temperature as the atmosphere; but whatever length they may be, this temperature will never be exceeded, even within two or three feet of the pump; that is to say, up to such a distance as its warmth is conducted by the metal of the pipes. The expanded air thus once more raised to the temperature of the atmosphere, by having absorbed heat from the sides of the pipes through which it has passed, is, previously to its expulsion from the pump, again compressed to atmospheric density. Its capacity for heat being thus diminished, that which it had taken up in the pipes changes from the latent to the sensible form. The same fact is observable in the compressing syringes used for igniting tinder, where the amount of heat developed in consequence of the decrease of bulk is sufficient to produce combustion.

The following experiment was made on the 7th of September, 1840, at the coal pit in the Forest of Dean (already mentioned). I placed a thermometer

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on the cover of the air pump previously to commencing work, which stood at 65°, and was so fixed as to receive the blast of air emitted from the pump, which, when put to work, created and maintained a vacuum of about 10lbs. In about ten minutes after commencing, the temperature 位 rose to 122°, and was still slowly rising; but the range of the thermometer being only 132°, I removed it. I believe it would have risen to at least 132° or 133°. As it is evident that the air in the pump being heated will not be of its original bulk when restored to atmospheric pressure, but so much greater as is due to its rise in temperature, an extra and wasted power in proportion to this الله increased volume must clearly be exerted by the bale prime mover. I have adopted two methods to obviate the loss arising from this cause, the one to fix the pump in a cistern, the other the application of injection cocks, by which an extremely fine jet E of water could be admitted. After the application of these cocks to the air pump at the coal pit above mentioned, the revolutions of the steam en

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Oral gine (which had no governor) were increased from thirty-one to thirty-six per minute, the same vacuum being maintained in the pipes. The air pumps at Woolwich and the London-bridge stathe tion were also fitted with injection pipes.

in the converse manner to the steam in an ordinary expanding engine, I should propose to compensate for it by working the pneumatic cylinder expansively; that is to say, by using a cylinder of one foot area of piston and two feet stroke, at 7 lbs. pressure, to admit the air for one foot (or half the stroke) only, as in the diagram. The work done by such a pneumatic engine would equal, first, the area of the piston multiplied by the 74lbs. pressure on each inch, and by the space moved through rough between A and B; and second, to be added to this.

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I will now point out a means by which a great part of the loss arising from the use of pneumatic The area of the piston multiplied by 2.9lbs. averengines may be avoided. As this loss has been

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this engine: as the atmosphere was excluded after can say from experience, this is easily overcome; Now to ascertain the size of the air pump for | practicability of making air-tight joints to the pipes, one foot only had been admitted, and as we have which is the more credible when we consider that again supposed half an atmosphere, or 7 lbs the force can never exceed 15lbs. per square inch, pressure, this one foot of air would expand to two and that we commonly see water-mains made perfeet in the pipes, as by the first calculation, and fectly tight under a far greater pressure than this. would consequently require the same size pump and the same amount of power to work it; but this has been previously ascertained to be 17,971 lbs. moved through one inch. Therefore, by the expanding arrangement, the work done and power required are rendered equal, thus confining the dloss to the friction and leakage, which, by common care, may be reduced to a very slight amount.

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Note, that the period of cutting off the air in the above arrangement must depend on the degree of pressure at which the pneumatic engine is worked. Having thus endeavoured to point out the causes of loss arising from the use of this method of transeferring power, and having suggested a probable means by which, in many cases, these losses may be reduced, I shall conclude by stating under what circumstances it appears desirable to employ it.

Whenever power for manufacturing purposes has to be conveyed a great distance, that is to say beyond the limits of shafting, or any contrivance of that sort, there can be no doubt that this plan is invaluable; and more especially as, from all I have been able to observe, it appears that the loss does not increase with the distance, but is a first loss.

In reply to any doubt that may be felt as to the

In Mr. Wrigley's colliery at Oldham, previously to the introduction of the pneumatic machinery, water and coals were drawn by horse power up an incline two hundred yards in length, the head of which was situated about two or three hundred yards from the bottom of a shaft of one hundred and fifty yards depth; so that the whole distance from the engine at the pit's mouth, which worked the air pump, to the lower end of the water elevator, was about three-eighths of a mile. The pneumatic pumping and winding machinery were applied to this incline in the year 1837, or 1838, and have since been working with the greatest success.

At Mr. Browne's coal pit near Manchester, a pumping machine has also been fixed, which works at a still greater distance from the moving power.

In similar situations to these, and in many others, such as working the cranes in an extensive dock, rendering available the power of a water-fall by transferring it from some almost inaccessible locality, &c., there can be little doubt that this is the only feasible means of accomplishing the object; but it is most absurd to employ it, as at Woolwich

and at the London bridge goods station, as a sub- dence of better qualities; moral courage, stitute for a reasonable length of shaft.

mental independence, worthy aims.

A new novel is sometimes a political event; slight enough it may seem, as in this case, but not unimportant. Symptoms of disunion have long been observed in the Con

With respect to its applicability to railways, though we cannot by expansion prevent the loss which occurs in the pump, as there is no reciprocation of the working piston, yet I think there is great reason to suppose it may, after certain difficulties of detail have been surmounted, come into servative camp, but without any increased successful competition with the present locomotive, consolidation or accession of strength on the the loss of power in which at high speeds is well part of the Whig opposition. The Whigs, known to be enormous. And when we consider as a body, appear to be still losing ground; that by the use of the atmospheric system, the carriage, not being in danger of a concussion with the engine, may be rendered as light in proportion to the number of persons carried as the common omnibus; and that the dead load of engine, tender, of sullen supporters. Old parties are breakand water will be totally dispensed with, thereby ing up. New combinations are forming. reducing the useless weight of the empty train to The moment is favourable to discussion. about one-half that of the persons carried instead Coningsby' is the yeast that will help in

of three times their weight, which is nearer the present proportion, we shall come to the conclu

sion that, taking into account the saving both of

first cost and wear of the way and carriages, and the reduction in tractive power from the decreased weight of the trains, that we can well afford a greater expenditure of force per ton, more especially in stationary engines, where there is less wear and consumption of fuel,

their influence with the country is feeble and daily becoming more so; and yet Conservatism is not popular; it can only boast

the general fermentation of ideas; and the result, although it may not advance the views of " Young England," or what Mr. D'Israeli calls the "new generation," must be favourable to progress.

Of Coningsby,' as a fiction, we shall not attempt a minute analysis. There is nothing original in the plot, and although many of

As compared with the rope, I think any person the characters are personal sketches, they acquainted with the Blackwall railway will allow that the atmospheric, even in its worst form, is far chiefly belong to the class with which the more economical. The average power of the sta- readers of fashionable novels have long been tionary engines at this railway is about 180 horse, familiar. D'Israeli has not the creative which, at the utmost, draw about one hundred tons faculty of Dickens. Coningsby, the hero, is at the rate of twenty miles an hour only; which, only the walking gentleman of the stage, at a tractive force of 10lbs. per ton, amounts to but and to many actors brought on the scene,

54 horse power, or 30 per cent.; thus giving a loss of 70 per cent., even supposing this load to be constant instead of diminishing by casting off carriages as the train proceeds.

In this last calculation I have taken the low number of 33,000lbs. as the unit of the horses power, instead of the real one of 52,000lbs., which would show the actual loss to be 81 per

cent.

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somewhat insipid parts are assigned. Flora
Villebecque is a failure, and perhaps the
principal blemish of the book. The unre-
quited affection of a youthful aunt for her
own nephew is not a subject for sympathy,
and such an incident gratuitously introduced
is not in good taste. Millbank, the manu-
facturer, bears little resemblance to the class ery
of which he is intended as a type. Many
of the wealthiest manufacturers rejoice in
the title of Conservatives; and those who
hate the aristocracy with the intensity of a
Millbank (if any such there be), do not send

eu

4

ART. II. Coningsby. A Novel. By B. their boys to Eton for the sole privilege of it D'Israeli, Esq., M. P. H. Colburn.

having them educated with noblemen's sons. The younger Millbank is a nobody, born

it

A CLEVER novel; -clever in the higher ac-only to be half drowned in a boat excursion, ceptation of the term. A novel that, wheth- and saved by Coningsby. The misunderer as a work of amusement, or a vehicle for standings of the hero and heroine, arising political opinions (the latter perhaps of ephe- out of gossiping rumours, belong to the stumeral interest), has been in the highest de- pid and common-place; but the novel has gree successful, and ranks, deservedly, with many redeeming points, and its interest selthe highest of its class. We speak freely of dom flags, least of all perhaps in the chapits faults. Upon the philosophy of Conings- ters devoted to the tender passion; the esby, our strictures will, for the most part, be sential ingredient of all romance. Our fair disparaging; but let us be just to a writer readers, we doubt not, would deem the de-a of merit. We have here, from the pen of scription of a ramble in a wood, the scene in Mr. D'Israeli, a work, not only calculated a fisherman's hut, where the lovers take to sustain his reputation for literary ability refuge from a storm, and for the first time and artistical skill, but one which gives evi- breathe their vows of unalterable attach

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"The people of Darlford, who, as long as the contest for their representation remained between Mr. Rigby and the abstraction called Liberal prinTV ciples, appeared to be indifferent about the result, the moment they learned that for the phrase had been substituted a substance, and that too in the form of a gentleman who was soon to figure as their resident neighbour, became excited, speedily tion enthusiastic. All the bells of all the churches rang when Mr. Millbank commenced his canvass; Ted the Conservatives, on the alert, if not alarmed, insisted on their champion also showing himself in all directions; and in the course of four-andtwenty hours, such is the contagion of popular feeling, the town was divided into two parties, the vast majority of which were firmly convinced that the country could only be saved by Mr. Rigby, or The preserved from inevitable destruction by the election of Mr. Millbank.

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"The results of the two canvasses were such as had been anticipated from the previous reports of the respective agents and supporters. In these days the personal canvass of a candidate is a mere perform. The whole country that is to be invaded has been surveyed and mapped out before entry; aurevery position reconnoitered; the chain of communication complete. In the present case, as is not unusual, both candidates were really supported by numerous and reputable adherents; and both had very good grounds for believing that they would ebe ultimately successful. But there was a body of the the electors who would not promise their votes; Conscientious men, who felt the responsibility of the duty that the constitution had entrusted to their discharge, and who would not make up their minds without duly weighing the respective merits of the two rivals. This class of deeply meditative individuals are distinguished not only by their

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""Jobson, I think you and I know each other,' says a most influential supporter, with a knowing nod.

"Yes, Mr. Smith, I should think we did.' "Come, come, give us one.'

"Well, I have not made up my mind yet, gentlemen.'

""Jobson!" says a solemn voice; didn't you tell me the other night you wished well to this gentleman?"

"So I do; I wish well to everybody, replies the imperturbable Jobson.

"Well, Jobson, exclaims another member of the committee, with a sigh, who could have supposed that you would have been an enemy?”

"" I don't wish to be no enemy to no man, Mr. Trip.'

"Come, Jobson,' says a jolly tanner.
If I
wanted to be a parliament man, I don't think you
could refuse me one!'

" I don't think I could, Mr. Oakfield.'
"Well, then, give it to my friend.'
"Well, sir, I'll think about it.'

" Leave him to me,' says another member of the committee, with a significant look. 'I know how to get round him. It's all right.'

""Yes, leave him to Hayfield, Mr. Millbank; he knows how to manage him.'

"But all the same, Jobson continues to look as little tractable and lamb-like as can be well fancied.

The

"The eve of polling-day was now at hand. This is the most critical period of an election. All night parties in disguise were perambulating the different wards, watching each other's tactics; masks, wigs, false noses, gentles in livery coats, men in female attire-a silent carnival of maneuvre, vigilance, anxiety, and trepidation. thoughtful voters about this time make up their minds; the enthusiasts who have told you twenty times a day for the last fortnight, that they would get up in the middle of the night to serve you, require the most watchful cooping; all the individuals who have assured you that their word is their bond,' change sides.

"Two of the Rigbyites met in the market-place, about an hour after midnight.

"Well, how goes it?" said one. 'I have been

the rounds. The blunt's going like the ward pump. I saw a man come out of Moffatt's house,

e pensive turn of mind, but by a charitable vein that mutfled up, with a mask on. I dodged him. It

seems to pervade their being. Not only will they was Biggs.'

Dat think of your request, but, for their parts, they wish both sides equally well. Decision indeed, as it must dash the hopes of one of their solicitors, seems infinitely painful to them; they have always a good reason for postponing it. If you be seek their suffrage during the canvass, they reply that the writ not having come down, the day of election is not yet fixed. If you call again to inform that the writ has arrived, they rejoice that perhaps after all there may not be a contest. If you call a third time, half dead with fatigue, to give them friendly notice that both you and your rival have pledged yourselves to go to the poll, they twitch their trousers, rub their hands, and with a dull grin observe

""You don't mean that, do you? D-e, I'll answer for Moffatt.'

"" I never thought he was a true man.'
"Told Robins?"

"I could not see him; but I met young Gunning, and told him.'

"Young Gunning! That won't do.'

"I thought he was as right as the town clock.' "So did I, once. Hush! Who comes here? The enemy, Franklin and Sampson Potts. Keep close.'

"I'll speak to them. rather late to-night??

Good night, Potts. Up

"All fair election time. You ain't snoring, are you?"

"Well, I hope the best man will win.' "I am sure he will.'

""You must go for Moffatt early, to breakfast at the White Lion; that's your sort. Don't leave him, and poll him yourself. I am going off to Solomon Lacey's. He has got four Millbankites cooped up very drunk, and I want to get them quietly into the country before day-break.'

""Tis polling-day! The candidates are roused from their slumbers at an early hour by the music of their own bands perambulating the town, and each playing the conquering hero,' to sustain the courage of their jaded employers by depriving them vous system. There is something in that matin burst of music, followed by a shrill cheer from the boys of the borough, the only inhabitants yet up, that is very depressing.

of that rest which can alone tranquillize the ner

"The committee rooms of each candidate are soon rife with black reports; each side has received fearful bulletins of the preceding night campaign, and its consequences are exemplified in the morning; unprecedented tergiversations, mysterious absences, men who breakfast with one side and vote with the other; men who won't come to breakfast; men who won't leave breakfast.

"At ten o'clock Mr. Rigby was in a majority of

twenty-eight.

66

The pollin

polling was brisk, and very equal until

the middle

one.

chinery has utterly failed. The kind of go-
vernment it secured is neither that of the

majority nor of the intelligent minority; it
has placed power in the hands of the venal.
With narrow and corrupt borough constitu-
encies on the one hand, and swarms of de-
pendent county voters on the other, we have
a system ingeniously framed, as it would ap-
pear, to give the ascendency only to the po-
litical Esaus of the community. Principle
is rarely in question. The determining con-
sideration is the mess of pottage. Neither
Whigs nor Tories choose their own men.
It is not sufficient to have talent, experience,
integrity; the candidate must be one who
can command the means to influence base-
ness. The member is practically elected
by men who have no opinions of their own,
and obey no impulse but that of their imme-
diate self-interest. These turn the scale be-
tween contending parties, and partially, or
wholly, defeat the object of both.
doubt if the system now in operation be not
worse than that it superseded. In former
days (we had almost written the good old
with the pres-

times, of the day, when it became very slack.

Mr. Rigby kept a majority, but an inconsiderable Mr. Millbank's friends were not disheartened, as it was known that the leading members of Mr. Rigby's committee had polled; whereas his opponent's were principally reserved. At a quarter-past two there was great cheering and uproar. The four voters in favour of Millbank whom Solomon Lacey had cooped up, made drunk, and carried into the country, had recovered their senses, made their escape, and voted as they originally intended. Soon after this, Mr. Millbank was declared by his committee to be in a majority of one; but the committee of Mr. Rigby instantly posted a placard in large letters to announce that, on the contrary, their man was in a majority of nine.

"If we could only have got another registration,' whispered the principal agent to Mr. Rigby,

at a quarter-past four.

"You think it's all over, then?"

""Why I do not see now how we rise. We have polled all our dead men, and Millbank is

seven a head.'

""I have no doubt we shall be able to have a good petition,' said the consoling chairman of the

Conservative association."

SO dissatisfied are we

We

ent), nomination boroughs were simply appendages to great estates; we have now the same appendages to great estates with certain incumbrances-electors to be demoralized.

We doubt whether under any of the forms of continental despotism the exercise of arbitrary power produces greater moral evils in small communities, than the corrupting influences at work under our existing electoral system. It is utterly detestable; and if it were not a mockery rather than a practical exemplification of the true theory of representation, we should at once abandon the defence of constitutional government. The Emperor Nicholas is not an authority we greatly respect, but it may be assumed that he sometimes speaks the truth, as this is generally admitted of that older potentate, whose name he bears. We quote, as apposite to our subject, a striking passage from the Marquis de Custine's 'Russia.'

"The interrupted himself, and looked

There is unhappily nothing exaggerated in this picture. It too faithfully describes that virtual representation which the country obtained by the Reform Bill; and we find ourselves perfectly in accord with Mr. D'Israeli, in pronouncing upon it the most emphatic condemnation. What Young England may do for our political regeneration, or that Chartism' which the author of 'Coningsby' considers all but inevitable, lies hidden in "Sire, I have always regarded representative futurity. The hopes once raised by the government as a compact inevitable in certain comReform Bill belong to the past. Its ma-munities at certain epochs; but, like all other com

at me attentively. I continued to listen without

replying, and he proceeded :

"I can understand republicanism; it is a plain and straightforward form of government-or, at least, it might be so; I can understand absolute monarchy, for I am myself the head of such an order of things; but I cannot understand a representative monarchy; it is the government of lies, C back even upon China than ever adopt it."

fraud, and corruption; and I would rather fall

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