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ture of these stations, as reported, was much higher than that observed by themselves, at places not remote enough to account for the difference. Let us hope, at least, for a little amendment in this direction.

Since the foregoing was written, we have received a copy of the proceedings of the Literary and Philosophical Society of Manchester. From these it appears that Mr. Vernon, F.R.A.S., has forwarded a letter from Dr. Buys Ballot, of Utrecht, in which the writer calls attention to the fact that the system of issuing storm warnings* was first suggested and carried out by himself at Utrecht, and not by Admiral Fitzroy in London, as is generally supposed in this country. He says:

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I laid down my principles before the Dutch Acad. emy of Sciences in October, 1857: in the Comptes Rendus de l'Academie des Sciences de Paris in November, 1857. I made my first proposal to the Dutch Government on the 14th of November, 1859, and the system was commenced on the 1st of June, 1860, or nine months sooner than in England. Í communicated a paper on the subject to the British and night-lamps will be difficult to improve are clack valves, and serve respectively for Association at the Newcastle meeting, land I upon, regard being had to the desirability of the admission of the external air to be comwonder that my system has not been adopted in displaying the signal to as great a distance as pressed, and for its escape after having underEngland, the more so because I recommended it to possible without interfering with established gone that operation. The two first valves, Mr. Francis Galton in August last. It is not only signs. To announce the weather at one sta- those for the ingress and egress of the water, a right of priority that I claim; but I think my tion, as Utrecht, is quite a different affair to are regulated by two small machines acting system is much better, though it gives no particulars as to rain or snow, but only the direction of that of announcing it around three kingdoms. independently, termed aëromotors, very simithe wind for the next twenty-four hours almost So far as we are aware the cones, drums, and lar to a vertical steam engine; their force is without fail, and the force or strength of the wind lamps and their symbols are Fitzroy's ideas about 28-horse power. The motion of the with great probability. It is a fact above all doubt entirely. We believe that the characteristics three valves situated upon the vertical branch that the wind that comes is nearly at right angles to the line between the places of highest and lowest of his daily forecasts-the least valuable part of the imaginary siphon is the result of the barometer readings. The wind has the place of of his scheme-were entirely his own; and that difference of the pressures acting upon their lowest height at its left hand, and is stronger in he was ready to defend them inch by inch with surfaces. The valve of admission is in comproportion as the difference of barometer readings anyone. As a matter of actual fact, storm- munication with the atmosphere; that of is greater. If Portsmouth and Valentia rise much signals were originated years ago. Madras escape, or, as we may say, of exhaust, leads above Nairn, then I think you will have a gale and Mauritius have for years had a mode of into large reservoirs in the form of boilers. from the west, and you have to attend to the Oscillation of that difference of barometer readings. Warning ships out of port, upon the commence- They are ten in number, and their capacity The only question is, how many hours does that ment of cyclones. So far as our investigation is about 22 cubic yards. These reservoirs difference take place before the wind comes? Now, has extended the winds over our islands appear serve the purpose of storing up the comI propose to introduce an instrument that in allfour to pass at an angle of 45 degrees to the line pressed air to be used as may be required. ports will simply show the azimuth in which he between the places of highest and lowest baro- The pressure in them is maintained constant greatest difference of barometer readings prevails, meter, leaving the place of low pressure on the by a manometric column of water reaching and the amount of that difference. The sailor acquainted with the meaning of the signs will have left hand, except when calms and light airs to 160ft. in height from the bottom. This to look at that instrument at the same time as the prevail. The rule cannot be properly exempli- column will not compress to more than six barometer. It is a new instrument that may be re-fied by a single example, and that given by atmospheres, though the rams compress to garded as a differential barometer, showing the state Buys Ballot is not one of the best. The baro- ten, but by the application of a regulating of the atmosphere in the surrounding countries. For many years weather signals after my method meter may be very low at Valentia as com- valve this degree of compression is attained. have been exhibited every morning at nine o'clock at pared with Portsmouth, with a westerly gale The modus operandi is as follows:-The water Utrecht: the strength and direction of the wind in the Channel. We should like particulars admission valve being opened, the column of are observed every hour, and compared with the of the new instrument; in our ignorance, of water in one branch of the machine, about prognostics, so that I could say how mary times the course, we cannot appreciate it. These things 85ft. in height, falls upon a mass of water, rule has held good, and how many times it has failed. Why does not the British Government may be managed better in Holland; but then which acts as a cushion, and deadens the send a distinguished meteorologist to Utrecht, in why are we so benighted regarding Dutch pro- violence of the shock. The vis viva of this order to see what we have done? I do not pretend gress? Cannot Dr. Ballot treat us to an ex- column drives the mass of water up to the to have found the whole truth, and acknowledge position of his experience of the prognostics exhaust air valve, which opens and allows that the rule may admit of exceptions in other of gales and storms "all reduced to measures the compressed air to escape into the resercountries; but in Holland we have had more expe- and time?" If he deems himself the inventor voirs already described. Directly the blow or rience of the prognostics of gales and storms than of storm-warnings, let circumstantial proof be shock is given the water admission valve all other countries put together, for here all is reduced to measures and time; in England and France presented. But, supposing the verdict be closes, and the exhaust opens and lets the all is vague, and in general expressions. either way, the British nation will ere long water out. At the same time the exhaust air exult over the indefatigable Fitzroy, notwith-valve closes, the level of the water sinks, and standing that his reputation is now temporarily a vacuum is formed in the compressive column or branch of the machine. The pressure of the external air being now unbalanced, opens the

clouded.

Now it appears to us that there is nothing tangible in this letter from Dr. Buys Ballot. Assertion is left unsupported by any reference to proof. Several persons may well claim the honour of having originated the idea and shown VENTILATION OF THE MONT CENIS two clack valves, which admit a fresh supply

the possibility of telegraphing the weather as a problem, and of forecasting weather as a

corollary, among whom may be named Ball, Herschell, Martins, Leverrier, Buys Ballot, Maury, Fitzroy, in the order of succession. Leverrier, in France, was the first who actually organised a grand system of meteorological telegraphy. Buys Ballot, in Holland, soon followed, and possibly was the first who deduced forecasts of weather from telegraphed data. It is not known to us, however, that he either established or suggested a system of storm-signals in any way resembling the great scheme so quietly effected by Admiral Fitzroy, for nearly the whole of the British coasts. Neither the one nor the other first suggested storm-warnings; but Fitzroy was certainly the first who carried them out as a national service. He was well versed in all methods of signals; and had been a member of the committee which devised the "Commercial Code of Signals" now rapidly coming into general use among maritime nations. His cones, drums,

More likely forecasts of weather.

TUNNEL.

of air ready to undergo compression. All the water being discharged from the machine, the compressive column is again filled with atmoclosed, that of admission reopens to allow of spheric air; the water discharge valve is the descent of the 85ft. column of water, and the operation is repeated as before.

N N order to ensure to the miners and other lengthened enterprise the necessary amount workmen engaged in this stupendous and of air, and also to effectually ventilate the tunnel in its progress, two descriptions of machines for compressing air are in use, the The pump machine is set in motion by the other on that of a pump. To prevent con- water acting upon a number of pistons. The one being on the hydraulic ram principle, the direct effect of a certain head and quantity of fusion, and to employ simple language, we compression of the air is effected up to six will call the first the ram and the other the atmospheres by means of six hydraulic wheels at the French or Modane end of the tunnel, as of a little over 2ft. and a stroke of almost pump. The former has not yet been worked and twelve pump barrels, having a diameter the local circumstances are more favourable to exactly 5ft. The wheels are provided with the employment of the other description of buckets, and receive each a motive force of machine. The rams, ten of which are arranged 70-horse power nominal, which enables them along each side of the face of the Bardonnéche to send into the storage reservoirs 55 gallons end of the tunnel, resemble an inverted of air per minute, at a pressure of six atmosiphon in shape, and are furnished with two spheres. The whole six wheels are, however, valves, one for admitting the water which is in order to allow for waste, leakage, and to set the machine in action, and the other for its escape after it has done its work. In the vertical branch of the supposed siphon three other valves are placed, two of which

every other possible cause of diminution, only considered as supplying per hour 785 cubic yards of air, which gives per day of eighteen hours 105,686 cubic yards at the

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above pressure. The total supply of air capable of being sent into the tunnel is 113,000 cubic yards every twenty-four hours. In a former number we have entered into a detailed calculation, demonstrating beyond a doubt that the safety and health of the workmen are fully ensured by these means, and that a large margin is left over and above to provide for any contingency in the matter of ventilation that human foresight could guard against.

PR

ORACTICAL trials, and experiments on an extended scale, have demonstrated beyond all doubt that petroleum is admirably adapted, as a substitute for coal, for the purpose of generating steam. But notwithstanding the convincing proofs we have had of this fact, we have not yet an example of an independent practical application. It is true the question of petroleum as a steam fuel is a comparatively young one, and in such a case it is always a hard matter to find anyone who will take the initiative. Besides, there are prejudices to be overcome, and conflicting interests to be disposed of, and until the way is clear in this respect, the most perfect method of effecting an improvement in any department of applied science, is not likely to progress very rapidly. But the question which meets us at the outset in the present case is, Have we arrived at to the furnace except tapping a hole or two be expected the different combinations of the most perfect method of burning liquid over the fire-door, and placing a sheet of iron parts and their manner of working present fuel! There are various systems by which it is proposed to effect this object, and there ratus could be cleared away, and the furnace time to time the subject of numerous patents. on the fire-bars. In half an hour the appa- almost endless variety and have formed from has been some deep thinking and hard be made ready for burning coal. working about the matter. But, although The action of a steam crane is exceedingly excellent results of the working of petro- the combustion was of the most perfect cha-power, which acts almost directly in winding In the trials we witnessed with petroleum simple, the essential feature being the motive leum furnaces have been recorded by us, it racter. An intensely brilliant violet flame and unwinding a drum to which the hoisting is only within the last few days that we filled the space beyond the bridge, indicating chain is connected. In all machinery the have felt an honest conviction that our ques- the thorough decomposition of the constituents great object at the present time is to utilise tion was answerable in the affirmative. This of the fuel, whilst the entire absence of smoke every square inch of material and make each conviction has been induced by a careful in- and unconsumed carbon added further testi- separate part do as much duty and in as many vestigation of the working of a new method of burning petroleum in the furnace of a steam mony to the soundness of the principle upon different ways as possible. It is not sufficient boiler, at a large works in Lambeth. The of the experiment, which lasted about two act sometimes as a strut if required, and it is The result for a rod or bar acting as a tie to be unable to apparatus with which these trials are now being hours, was the evaporation of 194lb. of therefore counterbraced to endow it with the carried on--which we need hardly observe forms the subject of a patent-is the invention water by every pound of oil used. During necessary strength and rigidity. In all cranes of Messrs. Wise and Field, of the Adelphi, 35lb. pressure to the engines driving the sidered as supported partly by the direct boiler supplied steam at hitherto constructed the weight may be conand Mr. Aydon, and, like most inventions possessing real utility, is very simple oil used was of the cheapest kind; in fact, the arm or tie. The strains developed in The action of the strut or jib and partly by that of in its character. The principle consists in the use of petroleum or any other liquid requires but very little attention, and is mately resisted by the post, but they form we believe, only refuse. The apparatus consequence upon these members are ultifuel for raising steam by injecting it, by means of superheated steam, into the furnace. This completely under control, the flame being in- the medium of conduction or transference. It creased or diminished in intensity almost in- is not absolutely necessary that there be any steam. We know what the maximum evapo- feature is wanting; but there must in all cases ration obtained from the best coal is, and be some equivalent resistance-a heavy weight when we find it more than doubled, as in the will answer-to counteract the tendency of present instance, by the application of petro- the load to pull the whole crane bodily over. a coal-burning furnace, what In many of the steam cranes this point may we not expect when the principle is de- d'appui is formed by the weight of the boiler boiler? It is early times yet with the inven- crane post. veloped in a specially constructed furnace and and its accessories, and there is virtually no tors, but they have succeeded in thoroughly mastering the principle of perfect combustion with, to a certain extent, imperfect apparatus. They have already achieved a success in burning petroleum in an ordinary furnace far beyond anything we had previously witnessed. Considering, therefore, the many advantages petroleum offers as a steam fuel, we may predict that with a perfect development of the principle, and with a modified form of boiler, its application must rapidly become general.

which the invention is based.

the trial the

various machines on the works.

is effected in such a way that it is vaporised stantaneously by regulating the flow of oil or post to the crane, as in many instances that

and dispersed over the surface of the fire, and its combustion completely effected.

The determination of the strains upon the various members of an ordinary crane is performed without much difficulty by the aid of a few simple formula. Thus, let W represent the weight of the load in tons to be hoisted or lowered, let L = the length of the crane post, and the angle of inclination of the jib with the horizon. Putting S for the resulting strain upon the jib, we have S =

It will be seen from the engraving on page 78 that the construction of the apparatus used in carrying out this invention is by no leum to means complicated. We show a section of the injector, to which the superheated steam is admitted through the pipe i. The admission of steam is regulated by a plug 1 passing the adjustable nozzle 22. The petroleum is admitted to the injector by the adjustable pipe j. A suitable quantity of air is mixed with the steam and petroleum in their passage though the pipe k2 to the furnace. This air is admitted through the opening k, and its amount can be regulated by means of the disc , which can be raised or lowered at will. We have thus a stream or jet of superheated Similarly steam, air, and petroleum, which is forcibly sin. 0° injected into the furnace through a pipe just if S, represent the strain upon the arm or tie above the fire-door. This jet impinges upon a W we find its value to be S, The bridge of fireclay placed a couple of feet or so tan. e' from the door. The fire-bars are covered with strain upon the crane post will be greatest at an iron plate, and on this a shovelful of live coal is placed for the purpose of igniting the the ground line and will equal the horizontal jet of petroleum spray. The air required for tion with the Thames Embankment, to con- which is the length of the post. Consequently the combustion of the petroleum is admitted vince one how general the employment of if S2 be this strain we find S, = W XL

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STEAM CRANES.

T only requires a visit to the works of new

through openings in the fire-doors, there being portable steam cranes is becoming. Wharf no upward draught through the fire-grate. In cranes, ship cranes, winches, and in fact the present instance the apparatus is fitted to nearly every mechanical appliance used for an ordinary single-flued Cornish boiler; its hoisting and lowering weights, can be now, if attachment, however, involves no alteration desired, worked by steam power. As might

=

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W

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The

post is evidently in the same situation as a cantilever with a load at its extremity. In this instance it must be borne in mind that the arm or tie is supposed to be horizontal, that is, the

the jib we find S=

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A very ingenious application of steam to the above purposes has been recently made by M. J. Chrétien, represented in the cut (p. 79). It has been employed for several months at the harbour of Villette, unloading vessels of merchandise and miscellaneous cargoes.

The

angle between its direction and that of the jib arts and in manufacture. Hitherto it can cell as before. The magnesium battery was is equal to 0. The more usual case, however, hardly be said that any really established use continued in action for sixty consecutive hours, occurs when the tie is inclined to the jib at a has been found for it. Even as a light-giving and maintained a deflection on the galvanodifferent angle than 0, and the calculations material its become a little more complicated. Making 0, that may be mainly owing to the fact that zinc was then put in action; the greatest deuse is not yet established, but meter ranging from 40 deg. to 28 deg. The to equal the angle between the tie and jib, we there has been no suitable apparatus to burn it in. flection given by it was about 30 deg., and in have for the strain upon the former, S, Mr. Larkin's lamp, so far as it has been tried, twenty-four hours the zinc plate was corroded W x sin. (90° — 0) is apparently the best apparatus yet invented into holes and had lost full one-half its orisin. For the strain upon for that purpose; but it is still far from per-ginal weight, whilst with the other battery W × sin. {90° + (9-0)}fect, as may well be supposed, seeing that it is a the magnesium plate had lost in sixty hours new invention, and its defects have to show only 43 grains, the loss of the zinc being about for in detail. Apparently the gravest diffi- times as much zinc was consumed as magnethemselves in actual use, and to be provided | 2oz. That is, in equal times, more than forty culty now to be overcome is the disposal of the sium. This is an extraordinary result, and, if volatilised magnesia, or rather the magnesia it be borne out in the trials that are now which is produced in impalpable powder on being made, tells marvellously in favour of the combustion of the magnesium, and much magnesium as a positive electric element. But heated magnesia smoke, as it may be termed, law established by Faraday has been too often resembles volatilised matter. This highly- we do not see how that can be possible; the condenses on the glass of the lamp, and con- verified to be so far at fault. siderably diminishes the light given out by of the positive element decomposed in all cases An equivalent the burning metal. Of course so brilliant a gives an equivalent of electric force, which will light can afford some diminution when thereby decompose an equivalent of any other elecsoftness is obtained, and that is the effect ob- trolyte, or re-deposit an equivalent of any tained by the condensed magnesia-it causes it other metal; so that if this be true, and we the newspaper correspondents at the Notting- ters at present doubts it, except perhaps Mr. to give a moon-like radiance, as described by think that no one conversant with these matham meeting of the British Association, but Rowland, we do not see how it is possible that this condensation must go on till it gets beyond there can be more than three of zinc to one of that, when it must absorb a great portion of magnesium decomposed, providing they are the light, and it is by no means a cheap light both precisely under the same condition, and to afford such waste, nor can it ever be, whilst no comparison would be trustworthy unless th metal is produced by means of sodium. they were. What is wanted is some kind of an exhaust, in addition to the chimney of the lamp, the exactitude of their experiments, and are to draw off the magnesia as it is formed pursuing them with great hope, so much so However, these gentlemen are confident in either into the open air or into a condensing that they think that electricity can be proall we can say to that is, we hope it can; but nesium that it can be by the use of zinc. Well, duced at one-tenth the cost by the use of magwe do not at present see how Faraday's law of equivalents is to be evaded. However, leaving

utility of the invention and the method of working will be apparent on explanation. In thus applying the direct action of steam power to the raising of loads the inventor kept in view the desirability of attaining the following results :-A rapidity of motion, facility of working, small consumption of fuel and expenditure in every sense, and the possibility of indicating the weight of the load at the time of its being hoisted, which is a novelty in machines of this description. The principal feature in the design is the long cylinder E, which is enclosed within, in fact constitutes the lower portion of, the iron jib F of the crane. Inside this cylinder works the piston, which is connected at the upper extremity with a pair of pulley's H, to which is attached the hoisting chain, which is fixed to the jib, as shown at K, near the intermediate pulley I. The slides for the admission and exhaust of the steam are represented at N. The boiler is indicated by A, and the tender, as it may be termed, carrying the coal and water, is shown by the letter B. It will be seen that one end of the double tie-bars G is

chamber.

light-giving material for domestic purposes
This material can hardly be introduced as a
by means of this lamp, as it requires some one
to manage it who is more competent than ser-
vants generally are; but, for special purposes,

attached to each side of the boiler, and, there- there is no doubt of its success. For the use of that about which we with many others are

fore, it, together with the tender, acts the part this lamp the magnesium is powdered, and for of a post, and counterbalances the moment of the the use of photographers it is made into load. The lever for regulating the action of ribbon and wire, and these are all the the steam is shown at D. The dynamometer

is indicated by T, and the rest of the diagram is self-explanatory. The crane we have just described has been brought, after many trials and disappointments, to a high state of perfection, and more than forty of various sizes and power have been ordered for different localities. The idea of converting the lower or other part of a hollow jib into a piece of mechanism inherent in the machine is not

new.

sceptical, we think there is an advantage in the use of magnesium over zinc, leaving out of the question the cost, though we do not think metal. The small quantities required for imagine; for in the best-arranged batteries not uses that have yet been found for the the difference would be so great as some analytical purposes cannot be reckoned in a more than half the zinc consumed produces a useable alloy, and by itself it cannot be used impure and much is consumed by local curuseful current of electricity, for zinc is always commercial point of view. It will not make a as aluminium can, simple moisture turning it rents on the plate itself. Still the difference facturers have been turning themselves in aforesaid is correct. There would be no local quckly into magnesia. Necessarily the manuin cost must be considerable under the most favourable circumstances-providing the law many directions for an outlet for their commo-action with the magnesium, for it is perfectly We believe that a water crane has been stood high as an electro-positive element; but pure, and for a single fluid or water battery dity. It has long been known that magnesium constructed in which this arrangement is its great positivity has been considered as a carried out in a very similar manner, but we bar to its use; any considerable surface of it zinc, providing the expense of each were magnesium would be infinitely superior to are not aware that steam power has ever been so treated before. being exposed, even to common water, Independently of the equal. would saving of space and the increased simplicity of causing not only the stoppage of the current, soon oxidise itself out of the water, thence action it is evident that a double duty, so to but also much waste of a very expensive maspeak, is got out of the jib of the crane. It not only performs the usual function of Owen Rowland to varnish the magnesium plate teral. But it has occurred, we believe, to Mr. sustaining a considerable share of the load, but or rod when used as an electro-positive elevirtually becomes the agent for setting the load in motion. At the same time it is not exposed to the solution. This metal being ment, leaving only the end of the plate or rod deprived of any appreciable amount of strength, for since all iron crane jibs and posts only is requisite to produce a sufficiently such a powerful element, a very small surface are, or ought to be, of a hollow form, it powerful current for ordinary purposes, that virtually amounts to an utilisation of space the sectional area of plate or rod is sufficient. which otherwise is turned to no account. By this means a large positive element can be There is no doubt that the jib has to be made introduced to ensure endurance of battery, and somewhat stronger when performing this double duty than if it had simply to act in its at the same time any desired surface can be ordinary capacity; but a slight increase in the brought in contact with the solution. thickness of metal would amply suffice to endow it with the necessary amount of extra strength. In mines, railways, harbours, wharfs, magazines, and in nearly every situa tion where a quick working and easily managed crane is required, we think that the one in question is likely to afford much satisfaction.

nesium with saline solutions, we do not think From experiments we have made with magthat a solution of sulphate of magnesium is the prefer a solution of salammoniac, one of best to use as an exciting fluid. We should saturated solution of salammoniac to twenty of sulphuric acid, or water slightly acidulated water, but common water with a few drops of fluids for magnesium. In fact, water slightly with common vinegar, are very good exciting acidulated with any fruit acid is sufficiently strong for this metal when used as an electropositive element; but perhaps common water will be found the most suitable exciting fluid when currents of small quantities and of long continuance are required, and the best negaof the magnesium works, have been making believe that these negatives are about to be Mr. Rowland and Mr. Mellor, the manager tive is platinised silver or graphite; and we experiments with a battery composed of mag- experimented with. nesium and copper, arranged as a Daniel's so good an electro-positive element as we exIf magnesium be found battery; a plate of magnesium about 2in. by pect it will-though we do not anticipate that 4in., well coated with varnish, except the its advantages will be anything like what bottom of it, in the outer cell; and a plate of the afore-mentioned gentlemen do-yet, if it copper inside the porous cell (this, of course, prove as good as we think it may, the demand with a solution of sulphate of copper), and in may be such that its price may be considerthe outer cell, a solution of sulphate of mag-ably lessened; and it will need to be before it THE MAGNESIUM VOLTAIC BATTERY. nesium, one part of the saturated solution of can come into general use, for at present, acINCE the production of magnesium on a work in comparison with this was arranged in equivalents, they stand in relation of price to the salt to thirty-two parts of water. To cording to our knowledge of electro-chemical have been the efforts to find a use for it in the 2in. by 4in., with copper negative and porous pence. forty-eight

The Action of Heat on Hydrocarbons-The
Origin of Petroleum and Bitumen.

NOTES ON RECENT SCIENTIFIC DIS- is the result of purely mineral reactions. at any instant be taken off the main drum, by a COVERIES AND THEIR PRACTICAL Starting with the hypothesis of Daubrée, who handwheel relieving the friction strap of the APPLICATIONS. believes that the alkaline metals exist in a free suspended weight by which it was tightened. state in the interior of our globe, M. Berthelot Two of these main winding drums were pro shows that by the action of these on carbonic vided as a precaution, but only one of them was A acid, and even earthy carbonates, at a high actually employed in laying the cable. N our number for December 14, some ac- temperature, acetylides of the alkalies are pro- necting the winding drum through spur gearing coupling arrangement was also provided for conIN count was given of M. Berthelot's expe- duced. These coming in çontact with the to a pair of trunk engines, so that the drum could riments on the synthesis of organic compounds. vapour of water, acetylene would be set free. be employed at any time for hauling in the por The author has mainly occupied himself with But as hydrogen and steam must also be tion of the cable already paid out, should any the study of those various compounds of carbon present, and all at a very elevated tempe- fault occur requiring such an operation; and this and hydrogen which are found among the pro-rature, the acetyline is unable to subsist, and constituted one of the most important improve ducts of the destructive distillation of coal in in its place we obtain the products of its con- ments over the arrangements of 1865, when it the manufacture of gas and oils; and the facts densation, and also the products of the reac- had been necessary to hand the cable along the he has recently arrived at seem to promise im- tion of hydrogen upon it. For example, he side of the ship from the paying out machinery portant results in these great industries. They says, hydrogen, reacting upon acetylene, forms in the stern to the picking up machinery in appear to indicate that the time may soon come ethylene and hydride of ethylene. A new re- the bow, on any occasion of requiring to haul in when we shall be able to form at will any one action of hydrogen, either upon the polymers the cable; and it was during this hazardous of the compounds, instead of a mixture which of acetylene or those of ethylene, will form process that the cable was broken and lost in the On leaving the winding gives the chemist infinite trouble to separate hydrocarbons of the marsh gas series, the former expedition. into its constituents, and which involves unne- same, in fact, which constitute American petro- drum, and before passing over the stern into the cessary loss of material to the manufacturer. leum. An almost unlimited diversity in these sea, the cable was carried over a pair of wheels, M. Berthelot has shown that the various hydro-reactions is possible, varying only according to midway between which was a weighted pulley carbons are produced under variable conditions the temperature and the bodies brought in bearing upon the top of the cable and guided in a vertical framing; this formed the dynamometer, of heat and pressure; and this point being contact. Thus, it would appear that all that indicating upon a scale the tensile strain on the reached, it only remains for these conditions to is necessary for the formation of the natural cable at each moment by the degree of deflection be accurately ascertained in order that the carbides of hydrogen is the intervention of of the cable under the loaded pulley. The total manufacturer may produce the compound he heat, water, alkaline metals, and carbonic acid. length of cable paid out was 1,851 miles, and the wants, and avoid the production of those he time occupied in making the distance of 1,669 does not require. miles from shore to shore was fourteen days.

We should state that an important practical application of the fact had been made by Mr. J. Young, jun., before the publication of M. Berthelot's results. Mr. Young has patented the distillation of the heavier hydrocarbon oils under pressure, whereby he states that these heavy oils are converted into lighter ones, possessing a higher commercial value. We have never seen any scientific account of Mr. Young's results, the publication of which would have much interest.

INSTITUTION OF MECHANICAL
ENGINEERS.

HE twentieth anniversary meeting of the
THE
members of this Institution was held on
Thursday, the 31st January, in the Lecture
Theatre of the Midland Institute, Birmingham;
John Penn, Esq., President, in the chair.

The Secretary (Mr. W. P. Marshall) having read the minutes of the previous meeting, the annual report of the Council was then presented, which showed the very satisfactory progress of Mr. Young practically (at least his patent the Institution during the past year, and its states so) effects his distillation at a pressure highly prosperous condition, with a large increase somewhat higher than 20lb. to the inch, in the number of members; referring also to the which indicates no great elevation of tempera-large and important annual meeting held in ture. At this stage it would appear that the Manchester last summer. more condensed hydrocarbons are broken up into lighter compounds. M. Berthelot, on the contrary, operating at very high temperatures, finds that the lighter hydrocarbons (gaseous and liquid) yield more and more condensed products, until, as the final result, he arrives at the complete dissociation of the carbon and the hydrogen.

As an example, we may quote what happens when light carburetted hydrogen-such a large constituent of our common illuminating gas-is exposed to heat. The first result is the production of a small amount of acetylene, a gas possessing far higher illuminating qualities. At a higher temperature, a bright-red heat, much more acetylene is formed, but at the same time naphthaline and some tarry matters are produced. Thus it would seem probable that while higher illuminating power might be given to gas exposed to heat, a more than equivalent loss of material might be sustained. We are writing, however, merely to indicate to the gas manufacturer a direction in which possibly highly valuable results might be arrived at by experiment. But we should say that beyond doubt a very high temperature would be prejudicial to gas. The acetylene we have mentioned as giving great luminosity is itself destroyed at a red heat, furnishing benzol and hydrogen.

The annual election of officers then took place, John Penn, Esq., being elected President of the Institution for the ensuing year. A number of new members were also elected.

The first paper read was a "Description of the Paying-out and Picking-up Machinery employed in laying the Atlantic Telegraph Cable;" by Mr. George Elliot, of London. The objects aimed at in the Atlantic telegraph cable expedition of 1866 were, firstly, the laying of a new cable across the Atlantic, and secondly, the recovery and completion of the one commenced and lost in the unsuc. cessful attempt of the previous year. The cable to be laid was coiled in three circular wroughtiron tanks built on the main deck of the "Great Eastern," and was kept covered with water during the whole time of the laying, so as to prevent depreciation of the gutta-percha coating, and afford an effectual means of constantly testing its electrical condition. In paying out the cable, it was passed first over a series of six deep grooved carrying wheels, called the jockey gear, and was pressed down into the grooves of the wheels by weighted jockey rollers, the wheels and rollers being all fitted with friction breaks. The whole of the jockey rollers could at any moment be simultaneously lifted off the carrying wheels, so as to let the cable slip freely through the grooves, in the event of its ever being necessary to let the cable run in order to ease the tensile strain upon it. The jockey gear thus served the purpose of giving a preliminary frictional hold The problem how to obtain from coal the upon the cable during the paying out; and the largest amount of gas possessing the highest cable then passed to the main friction drum, illuminating power is one far from being satis-round which it was coiled four times for obtaining factorily solved; and we believe these researches a firm hold upon the cable. On the shaft of the of M. Berthelot may greatly assist in the solution. For the scientific reader we may mention that the author's paper on the action of heat on hydrocarbons will be found at length in the December number of the Annales de Chimie et de Physique.

About the origin of coal there is no question, but geologists have been at a loss to account for the formation of petroleum, bitumen, and other natural hydrocarbons. On this point the researches of M. Berthelot throw considerable light, and he is led to conjecture that petroleum

drum were the two main break wheels, rendered
self-adjusting in their action by the arrangement
invented by the late Mr. Appold, and employed
in each of the previous expeditions of 1865 and
1858; a weight is suspended from the friction
strap, and the two extremities of the strap are
attached to a lever at different distances from the
fulcrum, so that whenever the friction strap is
carried round in the slightest degree by increased
friction of the break, thus overliftiag the weight,
the obliquity of the lever slackens the strap and
allows the weight to fall back to its proper posi-
tion. The whole effect of the friction break could

After

The new cable having been successfully laid, the next object was to recover the end of the cable lost in the previous year; and after splicing it to the additional length of cable brought out for the purpose, to complete the laying of the old cable. The picking-up machinery in the bow of the ship was made of much greater strength than the paying-out machinery, on account of the extraordinary weight and strength of the grapnel-rope employed for raising the lost cable, the breaking strength of the rope being as much as thirty tons. The exact line of the sunk cable having been marked by a couple of buoys, placed at a considerable distance apart by nautical observation, the ship was then made to pass slowly across the line of the cable, dragging the grapnelrope; and the hooking of the cable in a depth of two miles of water by the large five-pronged grapnel at the end of the rope was ascertained with sufficient certainty from the increase of strain indicated by the dynamometer. several unsuccessful attempts to recover the cable, in one of which it had been actually raised to the surface of the water, it was again hooked and raised 900 fathoms from the bottom, and then buoyed there; after which the "Great Eastern" hooked the cable again a few miles to the westward, and at the same time the "Medway" hooked it still further west. Both vessels then began hauling the cable up, and the "Medway" broke it at a depth of about 300 fathoms, so that the "Great Eastern" had then a loose end for raising to the surface, and the strain on the cable was much reduced immediately. The recovered cable having then been tested and spliced, the laying of the remaining 680 miles required to finish the original cable was proceeded with and successfully accomplished. Drawings were exhibited to the meeting of the several machines employed in the paying out and picking up; and also specimens of the new cable of 1866, the recovered cable of the previous year, and the grapnel-rope, together with the original charts of the laying and picking up, which were lent for the occasion by the kindness of Captain Sir James Anderson.

The next paper was "On the Composition and Durability of Locomotive Boiler Tubes in reference to Coal Burning," by Mr. George A. Everitt, of Birmingham. The question of coal burning in locomotive engines, and its conse quent action on the copper fireboxes and brass tubes, although one upon which great diversity of opinion prevails, has drawn attention to the importance of ascertaining the best alloy of brass for the tubes, and also to the necessity of overcoming the difficulties so often experienced from the copper firebox plates being of hard or brittle quality. A simultaneous deterioration has also been noticed in the quality of copper sheathing of ships' bottoms, the durability of which at the present time is far inferior to what it was several years previously. The explanation in each case appears to be that the quality of copper known as best selected, which is obtained by skimming off

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the upper surface or purest portion of the melted metal in the smelting process, has of late years been so much in demand that the skimming is now carried too far; whereby the cake copper left behind, from which the copper firebox plates for locomotives and the sheathing for ships' bottoms are made, is seriously deteriorated in quality. Recently a system of testing the best selected copper has been introduced with advantage by the Admiralty, and also adopted in the manufacture of locomotive tubes, a prescribed alloy of the copper with zinc being required to come up to a fixed standard of tensile strain, and to exhibit a fracture presenting a silky appearance in texture, which cannot be obtained with any but a superior quality of best selected copper. The practice has also been adopted for several years on the French railways, and to some extent in this country, of employing an alloy of brass for the boiler tubes containing a higher proportion of copper than formerly, which is believed to be beneficial as regards the durability of the tubes, particularly in resisting the action of sulphur in coal-burning engines with bad coal. The increased ductility arising from the larger percentage of copper may be expected to admit of some reduction in the thickness of tubes, and consequently in their first cost, without diminishing their durability; and the thinner tubes, offering less rigidity, will have an advan. tage in reference to the difference of expansion between the iron boiler shell and brass tubes of locomotive or marine engines. Specimens were exhibited of brass boiler tubes flanged over cold, to show the ductility of the metal containing the higher proportion of copper now employed for the purpose; and also samples of the standard test bars that had been subjected to the prescribed test of tensile strength, and showed the required silky appearance in the fracture when broken

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an extensive Government factory; it was evident, | obtained, and has since been examined chemi
however, that the manufacture of enamelled iron
vessels was one of the most profitable portions of

the establishment.

The actual production of the iron at these works is small as compared with the quantity used in the manufacture of machinery, &c. The blast furnaces, built according to the directions of the celebrated mining chemist, Karsten, are similar in construction to the largest furnaces in this country, and are excellent specimens of furnace building. The charges of ore, fuel, and flux are conveyed up shafts to the mouth of the furnace by hydraulic power in the case of two of the furnaces, and by mechanical power in the other cases. Hot air is used, and the blast is supplied by a very well-constructed engine of 50-horse power, which had been made at Gleiwitz.

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The whole arrangements connected with the tion of the metal under the most favourable conditions. The product of the furnaces was stated, however, to be ridiculously small compared with that usually obtained from blast furnaces of similar size in other countries. This circumstance is alone accounted for by an examination of the ore worked at Gleiwitz. It is an argillaceous, brown hematite ore, somewhat similar in appearance to yellow ochre, and containing sel. dom more, though frequently less, than 26 per cent. of iron. The greater proportion of it is in an earthy or pulverulent state; a small quantity of a somewhat better description of ore, containing about 30 per cent. of iron, and obtained in a less disintegrated condition, is added to the other ore. Small quantities of zinc, lead, cobalt, manganese, and arsenic were found in some specimens of the ore which have been submitted to analysis. The first-named metal occurs very generally, and frequently in considerable abundance in the upper Silesian ores. The coal obtained in Silesia, and used at these works, is also of an inferior description, crumbling to dust in the furnace, and yielding, only at very high temperatures, a hard, dense, difficultly combustible coke, which, however, though tolerably rich in sulphur, does not furnish more than 3.5 per cent. of ash or mineral matter-an important redeeming feature.

cally. The specimen was of a lighter grey than the generality of grey pig, and exhibited a closegrained but well-defined structure. It was found to contain a rather excessive quantity of silicium, and a considerable quantity of manganese, in which respect it is similar to other specimens of Silesian metal examined on a former occasion. The following numbers represent its percentage composition:-Iron, 91-93; carbon, as graphite 2:11; combined carbon, 0:15; silicium, 294; phosphorus, 0.34; sulphur, 0.03; manganese, 2:48; arsenic, copper, titanium, cobalt, traces. The principal portion of iron manufactured at Gleiwitz is refined in the gas-finery furnace already alluded to, and is then employed only for the best kinds of work. The quantity of metal to be refined is not sufficiently great to keep the furnace constantly at work; it is, therefore, only used at intervals of a month, and, when not

the foundry. Silesian iron, supplied from other works, is also used at Gleiwitz; a very large quantity of Scotch iron is, however, employed to make up deficiencies. It appears that while advantage is taken by the Prussian Government of the facilities afforded for the production of iron at the Gleiwitz works, by their vicinity to sources of coal and iron ore, they are principally maintained for the manufacture of steam engines and other machinery required by different Gov. ernment establishments, such as that at König. shütte, the manufacture of enamelled iron utensils and ornamental castings being added as a source of profit.

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trated the construction of the Silesian gas reverberatory furnaces in use at the Government smelting works at Gleiwitz and Königshütte in Upper Silesia, and in the following number we described the method adopted in working them. A considerable amount of interest has been evinced in the matter and several correspondents have desired further particulars, a recent one especially asking for a longitudinal vertical section. Through the kindness of Mr. James Anderson, of the Machinery Department at Woolwich, we are enabled now to place the desired section and further particulars before our readers. Our engraving represents a longitudinal section of Eck's furnace, and must be taken in conjunction with the previous description already referred to, a perusal of which, or a comparison of the present with the former engravings, will make the matter clear. The additional particulars, for which we have been asked and which we now give, have reference to the details of the working, and the results of these and other furnaces at Gleiwitz and Königshütte. The works at Gleiwitz comprise four large blast furnaces, with puddling and finery furnaces (one of these, a reverberatory furnace, being constructed upon Eck's principle), cupolas, rolling-mills and smitheries, extensive workshops, with lathes of the largest dimensions for turning and planing pieces of machinery (many of these being worked by The circumstances under which iron is smelted water power); foundries for shells and small at Gleiwitz cannot but be considered as very castings; ; ranges of coke-ovens, with the necessary unfavourable; the pulverulent state of the ore bearrangements for applying the waste heat to the ing alone an important obstacle to the proper generation of steam; kilns and mills for prepar- management of the furnaces. Nevertheless, says ing the ingredients used for enamelling cast-iron Mr. Abel, in his report, the quality of the product utensils, of which a great number are made; was most highly extolled by the experienced enamelling furnaces, and other requisites of this Director, M. Kalide, and the appearance of the branch of manufacture; workshops for the pre- slag, of the fracture exhibited by the pig-metal, paration of models and moulds (a variety of small and of the castings made from it, confirmed in ornamental castings, such as railings, figures, great measure the high opinion he entertained of candlesticks, &c., being also made for sale); and it. M. Kalide stated that two or three guns had extensive store-rooms for the exposition of the been cast at Gleiwitz, some years since, of the manufactured articles. It will be seen from this iron manufactured there, and that the proofs to enumeration, that a great variety of work is done which they were subjected had shown the metal (2-94) is higher than that usually existing in good at this establishment, some of which is of a nature to be well adapted to the manufacture of ord-grey iron, but in the Königshütte iron that which one would scarcely expect to meet with at nance. A sample of the Gleiwitz pig-iron was amount is exceeded by more than one-half. The

The Royal Ironworks at Königshütte are far more extensive than those at Gleiwitz, and differ essentially from the latter establishment in being exclusively devoted to the manufac ture and refinement of iron, the production of railway and other bar iron, and the smelting of zinc ores. It appears that the ores worked at Königshütte are than those at Gleiwitz, in fact, even worse, the percentage of iron being very small, and the mineral, from its peculiar pulverulent nature, difficult to enrich or purify by levigation, or to work in the blast furnace. The coal is of a very inferior kind, containing much sulphur and ash, and furnishing a hard, difficultly-combustible coke. The product of the blast furnaces is as small as that at Gleiwitz-and the pig-iron obtained, to jndge from the results of analysis of a fair sample which was procured, is very inferior to the Gleiwitz iron. Its colour is light grey, its structure close, and very small-grained, and it is so brittle as to be easily pulverised. Its fracture and physical properties were those of an iron rich in silicium; and that this is the case is seen from the numbers, representing the percentage composition of the metal:-Iron, 9122; carbon, 2-06; silicium, 466; sulphur, 004; phosphorus, 0'56; manganese, 146; copper, titanium, traces. The amount of silicium in the Gleiwitz iron

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