Page images

We say

by shot or shell ; and, consequently, unless it | the mode to be adopted in the realisation of the engineering firms in and out of London. But were uninflammable as well as unsinkable it great reform. There is no manner of doubt that in this instance no such course has been would be of little use. Mere “lightness, the establishment for making the national monies adopted. “Kissing” has been said to “go by "toughness, non-absorption of water, and cheap-1-the Royal Mint-might, with an amount of "favour," and so far as that pleasant operation " ness" alone will not therefore do. If we are outlay upon new mechanical appliances and is concerned the saying is doubless just ; but wrong in this we shall be glad if Mr. Atherton fitments inconsiderable in comparison with why the privilege of coining the monies of the will show us where our error lies; but he must the advantages to be derived therefrom, be State is to be subject to the same rule it is not not forget that “ liquid fire” is as veritable a made quite equal to the task of which ministers easy to see. Perhaps in the course of two or means of offence as the Armstrong gun, and have assumed the responsibility. The four or three months, and when Parliament is sitting, has proved its efficacy quite as decidedly. Of five hundred tons of bronze coins which would some Member of the Government may cncourse we are quite aware that a solid substance have to be pressed into being before the old lighten us on the point. would not be set fire to by the mere lodgment copper could be entirely superseded would, At present, the fact that the initiation of a of a red-hot shot in it, with no other access for with little expense, in the course of less than new coinage on a vastly improved plan, and air save the hole by which the shot entered. three years, and without any interference with which is destined to form an era in the minting But the explosion of powerful shells within such the production of gold and silver coins, be annals of the country, is to be taken out of the a substance would be a very different matter, struck on Tower Hill. Why, we ask-and the guardianship of Her Majesty's coiners and put and would, we think, in most cases have the public no doubt will reiterate the question into those of a company of Birmingham coneffect of setting it on fire. There can be vo why are we to have a contractor in Birming-tractors, is the one to which we have felt it great harm in offering the premiums proposed “ham employed to do the Mint's work ?" proper to direct public attention, and in by Mr. Atherton if there is the least chance of obtaining a very light fire-proof and water-ble. There is no sort of manufacture conducted our own duty. We publish on another page 2

To us such an arrangement seems inexplica- omitting to do which we should have omitted proof solid material

, because such a material by Government which requires in all respects copy of the paragraph named, and have merely would be useful for many

purposes ; we have so much caution and care as that of money, and to say that the Manchester Guardian has been no desire, therefore, to obstruct the action of no manufacture, therefore, which should be totally misinformed in regard to the fact that the Society of Arts in this matter.

more jealously hedged in by restrictions and the firm referred to therein have "executed the But, having said this, it remains for us to reservations. But here, without any shadow of

copper coinage for this country for many say further that even if such a material as we good, pecuniary or otherwise, the carrying out they have done no such thing. The Parlia

years." We are in a position to assert that have spoken of should be produced, and placed of a great reform in the coinage is, to be enin Mr. Atherton's hands, we should be disposed trusted to hands whose interest is not to pro- from 1805-6, when the last coinage of copper

mentary returns will demonstrate the fact that to ask wonderingly-What will he do with it? duce pieces of money so perfect as to defy the and we think the Society of Arts should con- cunning labour of the counterfeiter, but such as took place at Soho, up to 1852, and from 1855 sider this question before they accept his advice shall return the greatest amount of profit to to :1859, the whole

of the copper coins for Great below the water-line where would he place the chequer has not thought sufficiently upon the exclusively at the existing Mint on Tower Hill. engines, coals, provisions, powder, and all those subject, or he would not have sanctioned so

If the other statements of the paragraph were other stores which now are stowed in the lower gratuitously dangerous a proceeding.

as inaccurate as this with regard to the producparts of the ship? We know not how to con- " have sanctioned” it

, because from the terms tion of copper coin, why, it might be treated ceive a plausible answer even to this question of the paragraph in question it appears that with silence; but there is, as we have said, Will Mr. Atherton kindly help us out of the sanction has positively been given to it. Let truth in the averment that new engines and difficulty? We hope he will, if possible, for not the singularly favoured and fortunate firm new coining presses are being prepared for his own credit's sake. It is easy enough for in Birmingham who have obtained, without Birmingham contractors, and we allow the paraany man to make propositions in the form in competition, at least the promise of being en- graph to speak for itself. which the present one comes before us ; but it trusted with the highly important duty of supwill not do for a gentleman who has taken a planting the worn-out copper with the new

THE GREAT SEAL PATENT OFFICE wrangler's degree at Cambridge, and made mixed metal coins, imagine that our remarks as

LIBRARY. himself prominent in scientific discussions, to to the profits to be made by the transaction What is to be done in the matter of the Great leave his propositions utterly undeveloped.' It are at all personal. That would be a great Seal Patent Office Library? Over and orer is, we think, incumbent upon Mr. Atherton to error; our criticisms are based on the laws again the manifest want of increased accommoshow us what the “new modification" of ships which govern contractors in general, and not dation, not only for the readers who frequent of war is to consist in, assuming that the mate- themselves in particular. They may, for aught it, but even for the very books, has been pointed rial which he asks for is supplied. We should we know to the contrary, be quite as disposed out by the London press, from the Times downbe heartily delighted to find that he has the to make themselves worthy of the great occa- wards, and yet nothing has hitherto been done. design of the unsinkable war-ship in his mind. sion as any other firm in the kingdom, but they At the present moment the wretched passage This, in our judgment, would be worth a very are subject to the commercial law which bids which is by courtesy deemed a part of the library handsome "premium,” and the Society of Arts them “make as much out of the job” as they itself is actually being blocked up with shelves, woald perhaps do well to offer one for it before can. It matters not to us whether it be Messrs. in order to afford standing space for the newlythey offer the others. They need not fear any A, B, C, or H, who undertake the task, we say arriving volumes. As the Commissioners of very extensive competition. Of course it is it is not one for contract at all, and that the Patents appear to be so entirely neglectful of quite possible to build enormous rafts, and call Government is in error in making it one. But inventors and others, who contribute goodly them by the new name of “ unsinkable ships”; we do not understand why (admitting for a sums annually to the State, we turn to Mr. Edbut these can hardly be what Mr. Atherton is moment that the Institution which

we have, and munds, the Clerk to the Commissioners, who thinking of, since he talks of rendering " exist- which is kept up at a cost of some thirty odd must possess considerable influence in the “ing vessels” unsinkable, and since he must thousand pounds per annum, is incompetent to matter, and we ask him to see tbat something is know perfectly well that the time for abandon- the task), specifications should not be put forth speedily done. We know be has but little time ing real ships has not yet arrived. is he thinking of? We respectfully invite him breastplate-makers, stampers of gas-fittings, business as estate-agent in the north, coupled

What, then, to all and sundry engineers, button-makers, to give to the subject, because his large private to tell us.

&c., so as to give them also an opportunity of with his duties as Reading Clerk and Clerk for

competing for the coinage. That would appear Private Bills in the House of Lords (for u hich COINING BY CONTRACT.

to be a course so completely in order—when he receives but a paltry £1,500 a year), together It is not without an intense feeling of dissatis- once the question of contract or no contract is with other engagements, must necessarily abfaction that we have observed å paragraph answered affirmatively—that it is impossible to sorb much of his time and energy. But then,

going the round” of the newspapers intimat- understand why it has not been done as he receives £1,000 per annum from the fees ing, in terms too positive and plain to be mis- in this instance. When it was proposed of patentees, we have some claim upon bis attenunderstood, that the Government intend putting by Sir John Herschel, at the commence- tion, and would rather have his services bethe coinage of the new mixed metal monies ment of his mastership in 1852, to hand stowed upon the improvement of the library out to contract. Our readers are well aware over the entire plant of the Mint to contractors, than upon anything else. that the proposition for re-organising the in- who were to be bound under heavy penalties to For it is perfectly manifest that a public ferior coinage of England was first promul- produce coin of proper weight, standard, and library in connection with the Patent Office has gated at the commencement of the present finish, and to be always under the control of become indispensable. It is the only simple year–in the pages of the MECHANICS’ Maga- officers of the establishment appointed by the means which can be afforded to inventors for zine, and since that is the fact we naturally Treasury, the opportunity of undertaking the enabling them to act justly to themselves and assume to ourselves the right of comment upon contract was offered to the most eminent honestly to each other. There must be a place


in which they can make reference to the speci- | ence to them, especially as a company designed bear any required amount of strain without the fications of former patents, and to standard to carry them out is, we observe, in course of least possibility of injuring the insulation, works on scientific subjects. Moreover, the formation. Messrs. Wells and Hall-who, it either in the process of manufacturing, or by attendance at the present gloomy cavern proves should be remembered, have been engaged for elongation, or as it is being payed out from the how needful a library is felt to be.

many years in the manufacture and application vessel. Mr. Edmunds must see all this, and we ask of india-rubber in all its various forms-do

There are minor advantages in connection him to sct upon what he sees.

And we do so not themselves hesitate to pronounce pnre with this construction of submarine telegraph with the best of intentions, for we assure him rubber much superior to gutta-percha for in- cables of which it is not necessary here to speak, that his past inactivity in the matter is inducing sulating the conductors of submarine telegraph our object being simply to endeavour to get the people to believe that he is more than inactive cables. They tell us that, proceeding upon plan properly estimated. There are enormous —that, in fact, he is hostile to the very existence their own practical knowledge, they have interests at work in opposition to all great of the library. It is time, therefore, that he selected as their insulating agent pure india- changes in telegraph cable construction, and took action, and proved that he is neither a rubber, which has never before been used for nothing but the enlightenment of shareholders slothful nor a faithless servant of patentees. the purpose, and which is capable of bearing and the public will ever operate successfully in A thousand a year may seem a trifle to a gentle much severer tests than it is possible for gutta- favour of improvement. We sincerely hope man who has passed most of his life in a per- percha to sustain. “ It is a well-known fact,” that the apprehensions which many feel in conpetual glow of patronage, and enjoyed many of they say, “that gutta-percha is a very impure nection with the Government eontracts for calles the great gifts which Lord Chancellors and ex

gum, and has in it a very large portion of will be dissipated, and that the authorities will Lord Chancellors are able to bestow. But to

“woody substance, which must decay, and ulti- not fail to adopt a thoroughly reliable system plainer men a thousand a year seems a consider

“mately destroy the insulation. Moreover, of construction. able sum, and one which no man should put in

gutta-percha is liable to be very seriously inhis pocket until he has done something in return “jured by changes of temperature, which must

THE FOUNDER OF MECHANICS' for it. This is the kind of thing that patentees consequently affect the insulation to a very

INSTITUTIONS. are beginning to say, and it is only right that

“considerable extent. The patentees, therefore, the gentleman in question should know it. " consider that the use of pure india-rubber, as Mr. Carlyle tells us, and we all of course We appeal, therefore, to Mr. Edmunds.

"applied according to their method of insula- believe, that "no lie can live.” A lie is repug

We are tired of appealing to Sir Richard Bethell

; " frequent failures which occur in the insulation forces of the universe will war with it when

* tion, is the only permanent remedy for the nant to nature—age, to God, and all the natural Sir Henry Keating, and their colleagues, although they really ought to support us cordially in this in its pure state has," they continue, “ many great may be its origin, or how strong its sup,

of submarine cables. The india-rubber used ever they encounter it. It does not matter how matter. "Sir John Romilly, above all, being the advantages which gutta-percha does not porters; it must, sooner or later, be blotted only permanent Commissioner, ought to do his best for us. But Mr. Edmunds is the executive possess. It is perfectly free from grit and every out. officer. We turn to him in this emergency, and and capable of bearing without injury a very at Newcastle-on-Tyne that old and dismal error

other impurity; it is also permanently elastic Lord Brougham has this week been repeating we shall continue to look to him until something high degree of temperature, which is a most of his about the founding of mechanics

' instituis done. We shall not cease to urge our claims essential quality for all cables that have to be tions. George Birkbeck, he again says, was the upon his attention until our legitimate and press- forwarded to various parts of the world. Tele- author of them. “We seconded him, and no more. ing demands are complied with.

graph companies are therefore assured that the “We laboured as hard as we could, bat he becables manufactured by them will not be

gan it. He began it twenty years before he SUBMARINE TELEGRAPH CABLES. destroyed either by the process of paying out or

“established it in London. He began it at GlasIt is useless to conceal the fuct that submarine by lying in the holds of ships while proceeding “gow, where he delivered a course of lectures to electric telegraph cables, as hitherto constructed, to hot climates

. “The method of applying the working men. This was the origin of mechanics have been to a very great extent failures. There “india-rubber according to the patent of “institutions. He then transferred it to London is great reason to doubt whether their insula- “Messrs. Wells and Hall, admits of no defects

"for the sake of greater extension, and as being a tion has ever been perfect even when they have “in construction, but insures a certainty of more important place for large support. He it left the manufactories ; in many instances they electrical integrity which is altogether unex

was that propounded it in London also, and not have been greatly injured in transport from the sampled.” This is the language of the paten-only proposed it and furthered is, but spent works to their destinations ; they have very tees themselves, and will therefore, of course,

"large sums of money upon it, which his family frequently sustained great damage in the pay- be of little value of itself; but we must admit

"have never been repaid. These were the services ing-out process; and, finally, they have been they have grounds for their statement. By

“of Dr. Birkbeck, and he it is that we must call far too susceptible to injury even after submer- winding on successive ribands of the pure

"and always treat as the founder of mechanics' gence. All these things, of course, entail great rubber, the whole process of manufacture can

"instituies. He laboured, we seconded him, no expense and loss upon the proprietors of the be watched at every stage, and it is difficult to

doubt, according to our means in our different cables--who are generally the shareholders of see how any sort of defect can occur ; while, by

capacities. We were his fellow-labourers, but he companies-and it is not at all surprising that laying the successive ribands on partially over effectual remedies have been sought. each other, and in opposite directions, even if “step in social progress.”

was the first and the originator of this great With these facts before them, some persons a defect should occur in one fold it would be

These are Lord Brougham's present statehave leaped to the conclusion that gutta-percha, effectually neutralized by the next. These suc- ments. He is not insensible to our late stricwhich has been used as the insulating material cessive layers of india-rubber being again tures, for, in the words which we have put in in most of these failing cases, is not a suitable covered by a close-laid elastic cord, become so

italics first, he endeavours to avoid Mr. Robertmaterial for the purpose ; but we are by no pressed and amalgamited as to form one person's claim to be the founder by pushing the means prepared to go this length with them, fectly sound and impervious insulator.

origin of mechanics' institutions back to the because we know that much of the mischief has The external coverings of the cables thus time of the Glasgow lectures to working men. arisen froin causes not at all assignable to the insulated may be of various descriptions- In the second italicised sentence, however, he intrinsic qualities of the insulator. At the same either all of wire or in part wire, or in part a makes the distinct assertion that Dr. Birkbeck time, whatever there may be to say in favour mixed covering of prepared hemp and wire, as first propounded the London Mechanics' Instituof gutta-percha, it appears beyond question that may be desired. The coverings hitherto tion. The assertion is false—distinctly, unquespure india-rubber is, to say the least, in all re-adopted have usually been made upon the tionably, demonstrably fatse! We have before spects equal to it in this respect. Pure india- spiral principle. The consequence is, they have shown why it is so, will Lord Brougham atrubber properly applied is, in fact, a perfect a strong rendency to stretch and to kink, which tempt to show the contrary? Assertion, even insulator. Its proper application is, however, sooner or later destroys the insulation. These from him, and, although repeated a thousand a matter of immense importance. How, then, evils are entirely obviated by the covering pro- times, is not proof. Mechanics' institutions may this be effected ?

cesses adopted by Messrs. Wells and Hall, in sprung from the MECHANICS' MAGAZINE, and We honestly confess that we know of no which the coverings are braided on in a new originated in the brains of its first editors, Mr. method by which this is to be done with the and peculiar manner. The machinery employed Robertson and Mr. Hodgskin. If there were no same certainty of a good result as is secured by for this purpose (and which has been made with taint in Lord Brougham's noble nature he would the system lately introduced by Messrs. Wells great care and skill by Messrs. Easton and Amos) say the same. and Hall

. We have, on a former occasion, di- is constructed upon the general principle of rected attention to their plans ; but, as we have double hollow tube braiding machines, and so lately had occasion to inspect the machinery perfectly encases the insulated portions of the building the Temple Church is again open (free)

We are requested to state that that very beautiful completed for them by Messrs. Easton and cable that the whole tensile strain is brought every day froin ten till four. Divine Service on Amos, we think it desirable to repeat our refer- on the external covering which can be made to Sundays at eleven and three.

Ind. h. p.

ON THE TRANSMISSION OF HEAT OF Nature in the following way: a source of heat, the lime light, the power of crpssing an atmo. DIFFERENT

having a temperature of about 300° C., was placed sphere; but, when the heat is absorbed by QUALITIES THROUGH

at one end of the tube, and a thermo-electric pile the planet, it is so changed in quality that the GASES OF DIFFERENT KINDS.

at the other—a large deflection was the conse- rays emanating from the planet cannot get with The following is an authorised abstract of a quence. Round the astatic needle, however, a the same freedom back into space. Thus the lecture recently delivered at the Royal Institution second wire was coiled, thus forming a so-called atmosphere admits of the entrance of the solar under the Presidence of H.R.H. the Prince Con- differential galvanometer; a second pile was con- heat, but checks its exit; and the result is a tensort, by Professor J. Tyndall, F.R.S.:

nected with this second wire, so that the current dency to accumulate heat at the surface of the Some analogies between sound and light were from it circulated round the needle in a direction planet. first pointed out : a spectrum from the electric opposed to that of the current from the first pile. In the admirable paper of M. Pouillet already light was thrown upon a screen---the spectrum The second pile was caused to approach the source referred to, this action is regarded as the cause of was to the eye what an orchestra was to the ear- of heat until both currents exactly neutralised the lower atinospheric strata being warmer than the different colours were analogous to notes of each other, and the needle stood at zero. Here, the higher ones; and Mr. Hopkins has shown the different pitch. But beyond the visible spectrum then, we had two powerful forces in equilibrium, possible influence of such atmospheres upon the in both directions there were rays which excited and the question now was whether the removal of life of a planet situated at a great distance from no impression of light. Those at the red end ex- the air from the tube would djstnrb this balance. the sun. We have hitherto confined our attention cited heat, and the reason why they failed to ex. A few strokes of the air-pump decided the to solar heat; but were the sun abolished, and cite light probably was that they never reached question, and on the entire removal of the air the did stellar heat alone remain, it is possible that the retina at all

. This followed from the experi- current from the pile at the end of the tube pre- an atmosphere which permits advance and cuts ments of Brücke and Knoblauch. These obscure dominated over its antagonist from 40° to 50°. off retreat, might eventually cause such an accurays had been discovered by Sir Wm. Herschel, On re-admitting the air the needle again fell to mulation of small savings as to render a planet and the speaker demonstrated their existence by zero; thus proving beyond a doubt that the air withdrawn entirely from the influence of the sun placing a thermo-electric pile near to the red end within the tube intercepted a portion of the ra- a warm dwelling-place. But whatever be the of the spectrum, but still outside of it. The diant heat.

fate of the speculation, the experimental fact needle of a large galvanometer connected with the The same method was applied with other gases, abides—that gases absorb radiant heat of different pile was deflected, and came to rest in a position and with most remarkable results. Gases differ qualities in different degrees; and the action of about 45 degrees from zero. A glass cell, con probably as much among themselves with regard the atmosphere is merely a particular case of the taining the transparent vitreous humour of the to their action upon radiant heat as liquids and inquiry in which the speaker was at present eye of an ox, was now placed in the path of the solids do. Some gases bear the same relation to engaged. * rays: the light of the spectrum was not percepti. others that alum does to rock-salt. The speaker bly diminished, but the needle of the galvanome- compared the action of perfectly transparent coal. THE GREAT EASTERN AND STEAM-SHIP ter fell to zero, thus proving that the obscure rays gas with perfectly transparent atmospheric air.

ECONOMY. of the spectrum, to which the galvanometric de. To render the effect visible to the audience, a TO THE EDITORS OF THE “MECIANICS' MAGAZINE." flection was due, were wholly absorbed by the large plano-convex lens was fixed between two uphumours of the eye.

Woolwich Dockyard, 1st Nov., 1859. right stands at a certain height above a delicate Reference was made to the excellent researches galvanometer. The dial of the instrument was

GENTLEMEN,— With reference to Mr. Cheverof Melloni. In a simple and ingenious manner he illuminated by a sheaf of rays from an electric ton's objection (MECHANICS' MAGAZINE, No. 44,

V3 DI had proved the law of inverse squares to be true lamp, the sheaf being sent through a solution of p. 284) “ that the formula

does not do of radiant heat passing through air, and the emi. alumn to sift it of its heat, and thus avoid the fornent Italian inferred from his experiments that mation of air-currents within the glass shade of justice to the performance of the Great Eastern for a distance of 18 or 20 feet the action of air the instrument. Above the lens was placed a in the aspect of commercial excellence, namely, upon radiant heat was totally inappreciable. looking-glass, so inclined that the magnified image speed in conjunction with great transport capaThis is the only experimental result now known of the dial was thrown upon a screen, where the bilities and economic employment of power,” and regarding the transmission of radiant heat from movements of the needle could be distinctly ob. inviting my re-consideration of the subject, I beg terrestrial sources through air ; with regard to its served by the whole audience. Air was first ex

to refer Mr. Cheverton to pages 15, 16, 17, and transmission through other gases it was believed amined, the currents from the two piles being 18 of the appendix to the second edition of my that we were without any information. equilibrated in the manner described; the tube

“Essay on Steam Ship Capability," where he will It was, however, very desirable to examine the was exhausted, and a small but perfectly sensible find the superior dynamic capabilities of large action of such media--desirable on purely scientific deflection was the result. It was next arranged ships, as compared with smaller vessels, in a mergrounds, and also on account of certain specula. that the current from the pile at the end of the cantile point of view, fully recognized and demontions which had been based upon the supposed de- tube predominated greatly over its antagonist. strated by five tables devoted to that subject, portment of the atmosphere as 'regards radiant Dry coal-gas was now admitted into the tube, and namely: heat. These speculations were originated by its action upon the radiant heat was so energetic, Table No. 1, showing the SUPERIOR CAPABILITY Fourier, but it was to M. Pouillet's celebrated the quantity of heat which it cut off was so great, of large ships as indicated by a progressively inMemoir, and the recent excellent paper of Mr. that the needle of the galvanometer was seen to creasing rate of speed corresponding to a proHopkins, to which we were indebted for their move from about 80° on one side of zero to 80' on gressively increasing size of sbip, the ratio of chief development. It was supposed that the rays the other. On exhausting the tube the radiant displacement to power being constant. from the sun and fixed stars could reach the earth heat passed copiously through it, and the needle Table No. 2, showing the SUPERIOR CAPABILITY through the atmosphere more easily than the rays returned to its first position.

of large ships as indicated by the progressively emanating from the earth could get back into Similar differences have also been established in reduced ratio of power to displacement correspace. This view required experimental verifica the case of vapours. As representatives of this sponding to a progressively increased size of ship, tion, and the more so, as the only experiment we diverse action, the vapour of ether and of bisul. the speed being constant. possessed was the negative one of Melloni, to phide of carbon may be taken. For equal volumes, Table No. 3, showing the SUPERIOR CAPABILITY which reference has been already made.

the quantity of heat intercepted by the former is of large ships as indicated by the progressively The energetic action of the solid and liquid enormously greater than that intercepted by the increasing distance capable of being steamed compounds into which the element hydrogen latter.

without recoaling at a given speed, and with a enters, suggested the thought that hydrogen gas To test the influence of quality, the following given per-centage of the displacement appiomight act more powerfully than air, and the fol. experiment was devised. A powerful lime light priated to cargo. lowing means were devised to test this idea. A was placed at one end of the tube, and the rays Table No. 4, showing the SUPERIOR CAPABILITY tube was constructed, having its ends stopped air. from it, concentrated by a convex lens, were of large ships as indicated by the reduced contight by polished plates of rock-salt held between sent through the tube, having previously been sumption of fuel per ton of cargo at which goods suitable washers, which salt is known to be trans- caused to pass through a thin layer of pure water. will be conveyed a given distance, without reparent to heat of all kinds; the tube could be The heat of the luminous beam excited a thermocoaling, at a given speed. attached to an air-pump and exhausted, and any electric current in the pile at the end of the Table No. 5, showing how soon the admitted required gas or vapour could be admitted into it. exhausted tube ; and this current being neutralised advantages which result froin increased size A Thermo-electric pile being placed at one end of by the current from the second pile, coal-gas was become neutralised if on the strength of increased the tube, and a source of heat at the other, the admitted. This powerful gas, however, had no size alone, we undertake OBLIGATIONS which inneedle of an extremely sensitive galvanometer con- sensible effect upon the heat selected from the volve, on the part of the large ship, an increased nected with the pile was deflected. After it had lime light; while the same quantity of heat, from rate of speed combined with an increased distance come to rest, the air was pumped from the tube, an obscure source, * was strongly affected.

without recoaling. and the needle was carefully observed to see The bearing of this experiment upon the action

The investigations above referred to, as comwhether the removal of the air had any influence of planetary atmospheres is obvious. The solar on the transmission of the heat. No such influ heat possesses, in a far higher degree than that of that Dr. Franz had arrived at the conclusion that an absorp

• While correcting the proof of this abstract, I learned ence showed itself-the needle remained perfectly

tion of 3-54 per cent. of the heat passing through a column steady. A similar result was obtained when hy- • The quantity of heat is measured by the amount of of air 90 centimeters long takes place ; for coloured gases drogen gas was used instead of air: the galvanomettic deflection which it produces; its he finds the absorption greater ; but all colourless gases he

assumes show no marked divergence from the atmosphere. Thus foiled, the speaker put his questions to quality of passing through media may be taken as a test of

--Poggendorff's Annalen, xciv. p. 337.





municated by me to the Institution of Civil En- ; dynamic performance with reference to indicated / glass jar—the second of the kind which I al gineers, and published in April, 1851, present horse-power, and of her dynamic duty with re- tried, and which would not hold its charge for results conclusively demonstrative of the SUPERIOR ference to her consumption of fuel.

half a day). I found from 131° to 14° of torsion CAPABILITIES of large ships in the commercial I am, Gentlemen, yours very obediently,

required to bring the index to zero when urged point of view to which Mr. Cheverton now revives


aside by the electromotive force of ten zinc-copper attention; in fact, these papers were written by

water-cells. The Leyden phial held so well, that me when the keel of the Great Eastern was being

the sensibility of the electrometer measured in laid, and when scientificand speculative enthusiasm Proceedings of Societies.

that way did not fall more than from 13.3° tol were at their height, not merely to confirm the

in three days. The atmospheric effect ran use of, but to caution the pul lic as to the misuse

from 30° to above 420° during the four d which then appeared to me to threaten the intro

which I had to test it—that is to say, the electroduction of leviathan ships. If Mr. Cheverton will QUARTERLY MEETING. Oct, 18th, 1859.- William motive

force per foot of air measured horizontally now prosecute these investigations, taking, as he Fairbairn, Esq., F.R.S., &c,, President, in the from the side of the house was froin nine to one suggests, the simple displacement as the factor chair. The President announced the formation hundred and twenty-six zinc copper water-cells. and not the power thereof,” the result will, I of a Mathematical and Physical Section in con

The weather was almost perfectly settled, either venture to say, be the reverse of what he antici- nexion with the Society. Dr. F. Crace Calvert calm, or with slight east wind, and in general an pates as respects doing justice to the commercial presented, in the name of Mr. Arnaudon (from easterly haze in the air. The electrometer twice capabilities of the Great Eastern. But this

Turin), a paper, and samples of green colours within half an hour went above 420°, there being leviathan is now atloat, ready to test the truth or

used in painting and printing, and especially at the time a fresh temporary breeze from the fallacy of the theories that have been advanced, is a new compound, corresponding to the monohy. the effect of east wind was amply confirmed.

referred to two new cbrome greens, one of which east. What I had previously observed regarding respects the mutual relation of displacement

, drate of sesquioxyde of chrome Cr2 O HO. The Invariably the electrometer showed very high power, speed, and coal have not yet been conclu- author commences in his work to point out the positive in fine weather, before and during east wind. sively determined, it appears from the data of her qualities which a good green ought to possess, in it generally rose very much, shortly before a slight passage from the 'Bill of Portland to Tuscar order to be suitable for painting. (MECHANICS". Magazine, No. 42, p. 242 and 252) reviews in a few words the different greens which puff of wind from that quarter, and continued that with a displacement of (say) 17,500 tons, the are found at present in the market, together with high till the breeze would begin to abate. I

never once observed the electrometer going up distance, 400 nautical miles, was performed in 32 the nature and properties of the same. Begin- unsually high during fair weather without east hours with a consumption of fuel at the rate of ning with the history of the works already pub- wind following immediately. One evening in 250 tons per 24 hours, or 208-3 cwts. per hour, lished on this subject, he next gives the descrip- August I did not perceive the east wind at all, being at the average speed of 124 knots per hour, tion of his process for preparing his monohydrate when warned by the electrometer to expect it; with a consumption of fuel at the rate of 16-66 of sesquioxyde of chrome, and which consists in but I took the precaution of bringing my boat up cwts. per knot. These data give a co-efficient of exposing the bichromate of potash mixed with

to a safe part of the beach, and immediately dynamic duty with reference to coal (by the phosphoric acid and any desoxydizing agent (for found by waves coming in that the east wind must V3 Di

example, ammonia) for some time to the action of be blowing a short distance out at sea, although formula -), equal to 6326.

heat." The soluble salts are then removed by it did not get so far as the shore. I made a

washing On this assumption that the steaming speed of

slight commencement of the electro-geodesy which

The green so prepared has not only a beautiful I pointed out as desirable at the British Associa124 knots per hour requires 250 tons of coal per day; 13 will require 281 tons per day;

shade, but like that of Mr. Guignet (made by tion, and in the course of two days, namely, 14

decomposing the borate of oxyde of chrome by October 3rd and 4th, got some very decided water) possesses the curious property of remain results.

Macfarlane, and one of my former it is, however, to be hoped that the construction ing green under the influence of artificial light. laboratory and Agamemnon assistants, Russel, of the engines and boilers of the Great Eastern Dr. Calvert also presented some muslins printed came down to Arran for the purpose. Mr. Russel is such as admits of the introduction of modern by M. Camille Kæchlin, of Mulhouse, with and I went up Goatfell on the 3rd inst. with the improvements, whereby the consumption of fuel fuchsine, a product obtained from the aniline of portable electrometer and made observations, with reference to speed may be greatly reduced. coal tar. This colour was very remarkable from while Mr. Macfarlane remained at Invercloy,

It may be observed that on the passage to the exquisite bloom of the pink shade abtained constantly observing and recording the indications Holyhead, the engines were not continuously when fixed with albumen.

of the house electrometer. On the 4th inst. the worked up to their full power, and, therefore, that The following extract of a letter received from

same process was continued to observe simulthe capability of the ship for continuous high Professor W. Thomson, F.R.S., Honorary Member taneously at the house and at one or other of speed was not fully developed. This considera of the Society, &c., was read by Dr. Joule. several stations on the way up Goatfell. I have tion, however, will not materially affect the co- “I have a very simple domestic' apparatus by not yet reduced all the observations, but I see efficient of dynamic duty above deduced, for the which I can observe atmospheric electricity in an enough to leave no doubt whatever but that cloudconsumption of fuel per hour when working at easy way. It consists merely of an insulated can less masses of air at no great distance from the full power would be increased in about the same of water to set on a table or window-sill inside, earth, certainly not more than a mile or two, proportion as the cube of the speed would be in and discharge by a small pipe through a fine influence the electrometer largely by electricity creased, and, consequently, the co-efficient of nozzle two or three feet from the wall. With which they carry. This I conclude because I find dynamic duty by the above formula remains very only about ten inches head of water and a dis

no constancy in the relation between the simulnearly constant at whatever speed the ship may charge so slow as to give no trouble in replenish- taneous electrometric indications at the different be driven, so long as the displacement is not ing the can with water, the atinospheric effect is

stations, Between the house and the nearest materially altered.

collected so quickly that any difference of station the relative variation was least. Between The circumstances of the passage to Holyhead do potentials between the insulated conductor and the house and a station about half way up Goat. not appear to have admitted of exact data being the air at the place where the stream from the fell, at a distance estimated at two miles and a obtained as to the rate of consumption of fuel per nozzle breaks into drops is done away with in my half in a right line, the number expressing the indicated horse-power per hour by the screw and apparatus at the rate of five per cent. per half ratio varied from about 113 to 360 in the course paddle-wheel engines respectively; but it being second, or even faster. Hence a very moderate of about three hours. On two different mornings understood that the screw engines were worked degree of insulation is sensibly as good as perfect, the ratio of house to a station about sixty yards with steam partially superheated, it is probable so far as observing the atmospheric effect is con- distant on the road beside the sea was 97 and 96 that the consumption may not have exceeded 34 lbs. cerned. It is easy, by my plan of drying the at respectively. On the afternoon of the 4th inst., per indicated horse-power per hour, and on this mosphere round the insulating stems by means of

during fresh temporary breeze of east wind, assumption the co-efficient of dynamic perfor. pumice-stone moistened with sulphuric acid, to blowing up a little spray as far as the road station, mance with reference to displacement and power insure a degree of insulation in all weathers, by most of which would fall short of the house, the would be about 200. This is a low co-efficient for which not more than five per cent. per minute ratio was 108 in favour of the house electrometer a mercantile steam-ship, but it is about as high as will be lost by it from the atmospheric apparatus —both standing at the time very high-the I have ever known to be realized by any vessel of at any time. A little attention to keep the outer house about 350°. I have no doubt but that this which the ratio of mean draught to breadth was part of the conductor clear of spider lines is was owing to the negative electricity carried by 80 small as in this case of the Great Eastern, necessary. The apparatus I employed at Invercloy the spray from the sea, which would diminish namely, only 23 to 84, or 1 to 3-65. It may be stood on a table beside a window on the second relatively the indications of the road electroexpected to improve as the vessel shall be loaded floor, which was kept open about an inch to let meter." down to a deeper draught. The question involv. the discharging tube projeet out without coming

A paper was read by Mr. Hopkins, entitled ing, as it does, the merits of the type of form of in contact with the frame. The nozzle was only “On Irregularities in the Winter Temperature of the ship, is of great importance, and it is to be about two feet and a half from the wall, and the British Islands.” hoped that the Great Eastern will not be nearly on a level with the window-sill. The allowed to go to her moorings at Southampton divided ring electrometer stood on the table without having gone through the usual ordeal of beside it, and acted in a very satisfactory way (as forwarded a telegram to J. R. Stebbing, Esq., to the

The Chairman of the Great Eastern Company has a trial by repeated runs over the measured knot I had supplied it with a Leyden phial consisting effect that the great ship sailed from Holyhead on in Stokes Bay, in addition to her sea-trials for of a common thin white glass shade, which insu. Wednesday at 18 30 for Southampton, where she may determining the present co-efficients of her lated remarkably well, instead of the German be expected this evening (Friday).

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DR. SAMUEL NEWINGTON, of Ridgway Ticehurst Sussex, has just completed a patent for the ap- seed or manure is placed inside the hopper, and T', worked from the foot-plate by the connection paratus for distributing seeds and manure repre- attached to the moveable side a', and holes are D, which being separate from the connection B, sented in the annexed engraving. This apparatus formed through the side a' near its lowest edge, it will be seen that one or both of the retarding is applicable for distributing guano, lime, and all and through the box containing the seed, and as forces may be used at pleasure. The steam from kinds of dry pulverized manure, and for dis- the machine moves forwards the seed or manure the pipe C passes to cylinder E, actuating the tributing corn, grass, and other like seeds broad. is shaken out through these holes into funnels piston H and levers K, &c., and break-blocks N, cast. a is the hopper, to the upper part of which carried from the fixed ends of the hopper, and is which may be applied to all the wheels if desired, the shafts 6 b are attached. The side a' of the by them guided into the furrows, or the seed or but by preference they are shown attached to the hopper torns at its upper edge on the hinge c, so manure may fall on the platform I, and be guided leading and trailing wheels only of passenger that the lowest edge of the side a' can be moved into the furrows by pieces of wood screwed on the engines. On the steam being released, the weight to or from the lower part of the side a”; to the board at intervals. The holes in the side a' and of piston, rods, and levers will free the break-blocks lower part of the moveable side a' are bolted in the box are kept clear by means of wires; from the wheels. projecting pieces d d. A vibratory motion is com- these wires are fixed to a bar passing along the By partly closing (more or less) the throttlemunicated to the side a' by projecting blades, or upper part of the hopper, and pass down through valve, trains may be controlled when passing down teeth, e, on the axis f. On this axis there are the seed or manure to the holes, and as the side steep inclines io any desired speed, leaving in two ratchet wheels, into which pawls (turning on a' is moved to and fro, the wires enter and leave reserve in the case of heavy goods trains pins fixed to the bosses of the wheels i) are the holes, and so keep the holes free. Proper ap- especially) a great surplus of break-power to bring pressed by means of springs, which are also fixed paratus for forming the furrows may be attached the train to a stand quickly on any incline to the bosses of the wheels, so that the axis f is to the front of the machine.

namely, that of the steam-break herein described, only caused to rotate when the machine is drawn

and also that of the tender and van-breaks. In forwards; the rotation of the axis f causes the

illustration of this, an experiment, not included projecting blades e upon it to strike in succession AN IMPROVED METHOD OF, RETARDING in the table, resulted as follows:-On an incline against the projecting pieces d fixed to the move

of five miles, the gradients averaging 1 in 80 (de· able side a' of the hopper, and so give to it a vi

By ALEXANDER ALLAN, Engineer, Perth.

scending), and with a gross load, estimated at 200 bratory motion. The moving the side a' towards In the prevention of collisions, and their conse. to 210 tons, the throttle valve alone controlled and away from the side az allows the seeds or quently serious results, a few seconds are most the train from a starting speed of thirty miles manure to fall on to the blades e on the axis f, valuable: the danger also is, in most cases, first per hour to fifteen miles per hour over the whole and as the axis rotates, the seeds or manure fall scen by the man in charge of the engine. The distance. on to the board l, and the vibratory motion of the object of these improvements is, therefore, to give The partial closing of the valve may also be side a' also keeps the manure in the hopper the driver increased power of controlling the speed made to prevent violent slipping, as the wheels agitated. The board l at one edge turns on the of, and in stopping the trains ; and for this pur will only revolve in proportion (i.e., the traction hinge m, and a vibratory motion is communicated pose, and in order that the whole break power of will oniy be equivalent) to the quantity of steam to this board by its being connected by the chains any train may be brought into requisition in the allowed to escape from the exhaust-pipe, and this n to the vibrating side a' of the hopper, and the shortest possible time, it is recommended that, in may be regulated to any extent by the valve, seed or manure will thus be shaken off this board addition to the apparatus to be hereinafter de which can be worked with greater ease and nicety on to the land. The hinge c, upon which the scribed, a cord shall be placed within convenient than the regulator. moveable side a' turns, can be raised or lowered reach of the men on the engine, communicating With regard to reversal, it is known to be ex. by screwing or unscrewing the nut c', and the with a bell fitted up in the first break-van, by tremely difficult, if not impossible, to reverse an distance between the end of the side a' and the which means the guard may be apprised of his engine at speed, but it will be seen that, with full lower part of the side a’ can thus be varied, and assistance being required at the van-breaks. steam on the pistons, the closing of the throttle. by this means the amount of seed or manure dis The improvements consist of two distinct parts. valve, which is not effected by speed, produces a tributed on to the land can be varied. When it is 1st. By inserting a throttle or other valve in the result quite equal to that of reversal, whilst redesired to stop the seed or manure from de exhaust-pipe of the engine at A, so that by means versal itself is facilitated by a greater equalisation scending from the hopper, the end of the side a' of a connection B the driver can fully or partially of the pressure on both sides of the valves, and an can be drawn against the side a’ by depressing close the valve A. By the table of experiments increased break-power is obtained (see Table) the long arm of the lever o. A greater quantity appended, it will be seen, that by the closing of without the usual objectionable results of reversing of seed or manure may be allowed to fall from the this valve (the regulator being at the same time the engine whilst in motion. hopper by turning the pieces d d, so that they are open), a retarding force is opposed to the engine The combined effect of these appliances may not acted on by the teeth e on the axis f; the of equal power with the tender breaks, and for all further be shortly stated to be,teeth e will then strike against the end of the ordinary stoppages this can be used to bring the 1st. By the throttle-valve alone a power is exmoveable side a' of the hopper. A still greater train almost to a dead stand-the tender break erted equal to that of the tender breaks. amount of seed or manure may be allowed to fall being applied only for say the last dozen yards, 2nd. By use of the tender-breaks in combinafrom the hopper by raising the side a’ of the thus effecting a great saving in the permanent tion with the above, a doubling of this power is. hopper away from the blades on the axis f; for way, tender-tyres, and break-blocks.

obtained this purpose the side a’ is carried by hinges which The second part of the improvements consists of 3rd. By using the engines' steam break-blocks, can be raised or lowered in a similar manner to steam break to work in connection with the the throttle valve, and the tender breaks together, the side a'.

above valve in cases of great danger. The steam a retarding power equal to triple that of tho In arranging the apparatus for distributing is taken from the exhaust pipe by means of the tender breaks alone is brought out. seeds or manure in furrows, a box containing the pipe C which is supplied by a stop.cock or valve 4th. In addition to the above, by reversing,

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