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ON THE AURORA BOREALIS AS A

back to the poles, in the higher regions of the Sir John also speaks of the waving motion being

atmosphere. This general circulation is, no doubt, accompanied by a very perceptibly audible sound. WEATHER PROGNOSTIC.*

much modified nearer the surface of the globe, by This may be aided by the known property of BY MR. MURRAY GLADSTONE.

large islands, chains of mountains, and more highly condensed air to transmit sound to unusual T is upwards of thirty-six years since my especially by extensive continents, as they are distances; and I have a strong impression of

attention was directed to the aurora borealis heated or cooled down by the comparative pre- having myself heard a sound similar to that proas a weather prognostic. I was then residing in sence or absence of the sun's rays. But where not duced by the waving of a flag, when the aurora Chesbire, having frequently to cross the river influenced by such cases, and in those latitudes was playing actively. Mersey, and ride or drive several miles after where they have room to expand and find uninter As far as it is known, the identity of the light dusk, which gave much opportunity of observing rupted course over a wide and unbroken extent of flickering clouds, above described as seen by day, the aurora, and of remarking the nature of the ocean, the unvarying direction and perennial and of the aurora as visible at night, is å new weather which accompanied and followed its ap- nature of the N.E. and S.E. trade winds appears to observation ; and the following opinions, expressed pearance. I think it was generally seen when the prove the fact of a constant flow of air from the by men of great eminence in meteorological wind, if any, was light; and in winter inclined to poles towards the equator. On their approaching science, while in no instance identical with the be northerly, with a tendency to frost ; and when the equator, these winds, as might be anticipated theory here proposed, may, it appears, be not the corruscations were vivid, and particularly if enter a zone of frequent calms, and are lost. This unfairly adduceri in its support. Beccaria, in the extending towards the zenith, or showing much constant supply of air, poured from both poles last century, offered a suggestion that there was a motion, I remarked that the aurora was almost towards the equator, must find vent in some way ; constant circulation of the electric fluid between invariably followed by a gale of wind, with rain, and while running down the N.E. trade winds on north and south ; but he gave an explanation from S.W.-within from forty-eight hours to four a voyage to India, I have repeatedly observed, different from the foregoing of the manner in days. The more brilliant and lively the appearance through the intervals of the lower clouds, detached which he conceived it might take place. Herschel and motion of the aurora, the earlier the gale thin ones moving at a great elevation towards the states his idea, in general terms, that the northern which followed took place, and the greater was its north, and directly against the course of the trade lights are produced by the electric fluid ; and severity. Slighter manifestations of the northern winds and of the much lower but heavier stratum Admiral Fitzroy, in his report referred to above, lights were not followed by any appreciable change of vapour carried along with them.

“On the Polar and Equatorial Air Currents," has of weather.

At the changes of monsoons, the opposite winds the following passago :-"We find here that the One of the most striking appearances of the are found charged, respectively, with negative and main currents, polar and equatorial, have very aurora I ever witnessed was at Corrimony, on positive electricity, and heavy storms of thunder different electrical characteristics—one, the polar November 18 , 1848. It was of a deep ficry red and lightning result on their meeting; and the being always plus, the other, always minus :-if colour, and extended all over the heavens; even

same is observed in a minor degree when easterly pure, unmixed with the polar.” There is, besides, from the zenith down to the summits of the southern and westerly winds meet. Magnetism, so powerful the well-known experiment of passing an electric hills ; and within two days it was succeeded by in the higher latitudes, is weakened towards the spark, in vacuo, through a glass tube, when it preone of the most violent storms of wind and rain equator; and if it may be inferred that, in like sents the appearance of the aurora borealis, even from the S.W., I ever witnessed in that part of the manner, the positive electricity brought by the with its play. kingdom. I was only within the last four or five atmosphere from the poles is discharged on I would only further advert to the fact, men. years that I met with an extract from a news- approaching the equator and becomes negative, an tioned above, that the remarkable aurora in paper-published, at the time, in one of the mid- explanation would be afforded of the cause and November, 1848, was not followed by rain, where land counties of England-in which reference was nature of the aurora borealis. This is distinotly seen in England; while within two days after its made to the same appearance of the aurora borealis ; given as his opinion by the late Admiral Fitzroy, occurrence, there was a perfect deluge of rain, and on the same date, and about the same hour in the in his report of 1864, on the Polar and Equatorial almost a hurricane, in Invernesshiro. If, on evening, eight or nine o'clock. It gave a similar Air Currents.*

reaching a few degrees further north, the column description as to colour, extent over the visible

When a larger body than usual of light air from of air from the south had come into contact with horizon, &c., but added that it was not followed, the south begins to descend upon the upper surface that from the north in sufficient force to drive it " as usual,” by westerly wind and rain. I would of the stream from the north, as those opposite back on the surface of the earth ; in other words, call attention to this fact, as it sorves to illustrate a

currents in the atmosphere come into close had proceeded so much farther downwards on its theory I would offer in explanation of the pheno- proximity, their negative and positive electricities course to its ultimate depression near the pole, as menon generally.

produce corruscations. The rarity of the atmo- thereby (in consequence of its necessary contact I would only further notice an observation some- sphere and the great elevation probably prevent with the colder northern atmosphere) to condense what different in kind, and made during the day; at least, for the most part), any sound or thunder and discharge the vapour with which it was itsel it was mentioned by my griove, soon after I went being heard ; and the former cause, joined with loaded, but which it was too high up to get rid of to reside in Elen Urquhart, 26 years ago ; and he tho manner in which the currents approach each when seen in the centre of England ; if this were was one of the most observant and intelligent men other, may probably occasion the shooting, flicker- the case with that remarkable aurora borealis, may of his class I ever met with. On a brilliant after-ing movements of the aurora, and of the clouds it not likewise, without unfairness, be deemed å noon towards the end of summer, I happened to formerly mentioned as being seen by day. The corroboration of the theory suggested ? remark to him, how very fine the weather had arches of boreal light frequently seen stretching been and was, when, shading his eyes from the from E. to W., may be produced by large masses of

BALLOON OBSERVATIONS. sun, and looking up over head, ho replied that air, charged with opposite electricities, meeting

(N a communication addressed to the Aca my notwithstanding, there would be rain in three days, each other and feeding the flame, quietly and con" for he saw it in the sky;" adding, he found this tinuously, on an extended front; while the mover of the phenomena he observed during a late scienalmost always right. On'inquiry, and looking up ments of light occasionally occurring throughout tific ascent in an air-balloon. in a similar way, I discovered that what he saw the length of these archos, may arise from the he states that its intensity is propagated to a con

As regards sound, was a faint streaky cloud, nearly in the zenith, masses of vapour coming more actively into considerable height in the atmosphere. Thus, he heard with a shooting and sort of wavy motion towards tact at particular points, and lighting up a corrus- the whistle of a steam-engine at an altitude of its southern margin. This prediction was verified cation, which, like a running fire, passes along the

3,000 metres; whole line.

the noise of a railway train passing, in the instance here referred to; and as often, afterwards, as I happened to remark the same

at 2,500 metres; the barking of dogs, at 1,800

When the corruscations are more than usually appearances, but my attention was never so much, vivid, or violent in their motion, it would indicate metres; the report of a gun, the same; the cries the nocturnal phenomenon ; and I do not, from my air from S. or S. W., which, in a shorter or longer and the music of an orchestra, at 1,400 metres ; nor from its nature, so often directed to this as to a larger arrival than usual of negatively electric of a large crowd, the crowing of cocks, and the own experience, speak of it with the same con- time, according to its strength, first checks, and the rumbling of carriages on a stone pavement, at fidence-but I cannot resist the conclusion that it then overpowers the N. or N.E. wind generally 1,200 metros; the human voice, at 1,000 metres is the same meteor, only presenting a different blowing when the aurora is seen. appearance as soon at night, and in bright sun- perature of the atmosphere, cooled down by the (5-8ths of a mile); the croaking of frogs, 900; light.

recent northerly wind, condenses the moisture and the chirping of a cricket, at 800 metres. It From the frequency with which the aurora was borne by that from the warm south, and precipi- is not so in the case of a descending sound; for at one time brought before me, I was gradually led tates it in showers; or, in more extreme cases, in the voice of the aeronaut, at an altitude of 100 to form some theory explanatory of its nature, and storms of rain. If I do not mistake, Sir John Ross metres cannot make itself heard distinctly. The of the weather changes I had observed to succeed describes the aurora in high northern latitudes, in clouds offer no impediment to an ascending sound. it, which I here submit, with diffidence, for con- winter, as being frequent, almost constant, as well is about 310 metres. T'ho quiet waters of a lake

average velocity por second in the latter case sideration. I would first notice a remark made, if as very near the earth. The cause of this seems I recollect aright, by Sir John Ross, the Arctic to be the opposing currents being then close to the echo the sound best upwards. While the balloon

moves in obedience to the current, its shadow navigator, that the aurora was confined to the point where they must necessarily come into conlower (or lowest) regions of the atmosphere. That tact, and where even the smallest portion remain sweeps either the earth or the clouds. It is genethis should be tho case in very high northern lati-ing of the opposite electricity must be discharged. rally black, but it sometimes happens that, falling

upon a darker spot than itself on the country, it tudes, would be quite in accordance with the theory I have formed. That the reverse is the case

* " We have also found the telegraph wires much assumes rather a luminous appearance. In this

disturbed when these main (principal) currents were case, examined through a telescope, it is found to in our own country may be inferred from the ap- beginning to act positively in force. No great tempesta consist of a dark central nucleus surrounded by pearances in Invernesshiro, and in England in November, 1848 ;-and, I believe, from many graphists say); and I am led by these, with other con. forest it appears yellow. On the clouds, when they

1860 without more or less wire disturbance (as the tele- luminous penumbra. On the green trees of a similar phenomena being observed, at the same comitant facts, and examination of numerous sea records, are white, and at the moment of issuing again into times, over wide ranges of the lower latitudes. as well as registers on land, to believe that such electric the pure sky with the sun shining, the air balloon But this, if correct, is equally in accordance with magnetic storms, sedulously watched now at mavy is minutely depicted with all its details, and of a the theory.

observatories, are results of atmospheric storms, some greyish hue. When it has reached an altitude of In explanation, I will suppose it may be where in one hemisphere or other, instantaneously felt 3,000 metres, the sky appears' dark and impeneassumed that the air passes from the poles through the air, however remotert on .conduction in the trable, in proportion as there is a diminution of towards the equator; where, being rarefied, it middle of a deep ocean, even the South Pacific.” The moisture. The light of the rising sun appears to rises, and, in considerable degree, at least, returns Rev. P. Secchi, Director of the Roman observatory, in penetrate through every terrestrial object, while

writing of magnetie currents in a wire in the magnetic that of the moon, which is always red, seems only

meridian, states that disturbances in it indicate the ap-
* Literary and Philosophical Society.
proach of storms as well as the barometer,

to glide over them.

ON COMBUSTION UNDER PRESSURE.* manifestly impossible that this substance should temperature in this case is probably greatly inferior BY PROFESSOR FRANKLAND.

exist in the solid form at the temperature of the to that produced by the combustion of phosphorus THE author commenced by stating that the phosphorus flame, which far transcends the melting in oxygen. We have not all the necessary data point of platinum.

for calculating the temperature of these flames, but from observing the way in which candles burned

For these reasons, and for others which the according to Andrews, phosphorus burnt in oxygen at the top of Mont Blanc, and the law deduced speaker had stated in a course of lectures on coal gives 5,747 heat units, which divided by the weight therefrom was that the diminution of illuminating gas, delivered in March, 1867, and printed in the of the product from one gram of phosphorus, gives power was exactly in proportion to the diminution incandescent particles of carbon are not the source it gives only, according to the same authority,

** Journal of Gas Lighting," he considered that 2,500 units. When phosphorus burns in chlorine, some years ago, while he was on the summit of of light in gas and candle flames, but that the 2,085 heat units, which, divided as before by the Mont Blanc at night, he was struck with the want luminosity of these flames is due to radiations from weight of the product, gives 470 units. It is of illuminating power in the candles burnt in the dense but transparent hydrocarbon vapours. As a therefore evident that the temperature in the latter tent in which they stopped for the night. He had further generalization from the above-mentioned case must be greatly below that produced in the observed similar results in other elevated regions. experiments he was led to the conclusion that dense former, unless the specific heat of phosphoric The diminution of the illuminating power was, in gases and vapours become luminous at much lower anhydride be enormously higher than that of phosall probability, due to the reduction of atmospheric | low specific gravity; and that this result is to a found that if the temperature of the flame of phos

temperatures than æriform fluids of comparatively phorus trichloride. The speaker had, in fact, pressure. If they took an ordinary gas flame, and placed a

great extent, if not altogether, independent of the phorus, burning in chlorine, be raised about 500deg. piece of paper with writing on it against the flame, that the gases of low density, which are not that extent, the flame emitted a brilliant white

nature of the gas or vapour, inasmuch as he found Cent. by previously heating both elements to read the writing as well or nearly as well as if the luminous at a given temperature when burnt under light. flame were not there at all.

common atmospheric pressure, become so when To return to ordinary luminous flames, the The commonly-received opinion was that we

they are simultaneously comprossed. Thus, mix- argument of the necessity of solid particles to. must have incandescent solid or liquid substances amit but little light when thoy are burnt or ground; and a closer examination into the evidenco

tures of hydrogen and carbonic oxide with hydrogen explain their luminosity obviously falls to the in order to produce a white light in gaseous flames. exploded in free air, but exhibit intense luminosity of the existence of these particles reveals its exIn following out this subject he had been brought when exploded in closed glass vessels, so as to treme weakness. Soot from a gas flamo is not into contact with a number of flames which emitted a considerable amount of light, but which did not prevent their expansion at the moment of com- elementary carbon ; it always contains hydrogen. contain any solid matter whatever.

One was
bustion.

The perfect transparency of the luminous portion metallic arsonic, burnt with oxygen gas. It emitted

In a communication just made to the Royal of flame also tends to negative the idea of the prean intense and brilliant white light. Bisulphide of Society, the speaker had described the extension sence in it of solid particles. The continuous carbon also einitted a very intense light; indeed, so

of these experiments to the combustion of jets of spectrum of gas and candle flames does not require, intense that it had been employed to take instan- hydrogen and carbonic oxide in oxygon under a as is commonly supposed, the assumption of solid taneous photographs. This was produced without pressure gradually increasing to twenty atmo- particles. The spectra of the flames of carbonic the possibility of a solid or liquid matter existing spheres. These exporiments, which were conducted oxide in air, of carbonic disulphide, arsenic, and in the flame while the light was being evolved. If in the laboratory of the Royal Institution, wero phosphorus in oxygen, are continuous, and so, as oxygen and hydrogen were enclosed in a soap with a thick glass plate of sufficient size to permit oxygen under a pressure of ten atmospheres. It is

made in a strong wrought-iron vessel furnished we have seen, is that of hydrogen burning in bubble or other light envelope, and exploded, there of the optical examination of the flame. was scarcely any light produced, but if they were

The to the behaviour of hydrocarbons under the inenclosed in a strong vessel and exploded by means appearance of a jet of hydrogen burning in oxygon fluence of heat that we must look for the source of an electric spark, at the moment of their com- under the ordinary atmospheric pressure was of luminosity in a gas flame. These gradually

exhibited. bustion the light would have an increased lumi

On increasing the pressure to two lose hydrogen whilst their carbon atoms coalesce nosity to the extent of ten times above that in the atmospheres, the previously feeble luminosity was to form compounds of greater complexity, and conprevious case. Ignited gas emitted light in pro- ten atmospheres pressuro, the light omitted by a gas, c# 4, becomes acetylene, C 2 H 2, and the

shown to be very markedly augmented, whilst at sequently of greater vapour density. Thus marsh portion to its density. The increase of luminosity jet about one inch long, was amply sufficient to density increases from 8 to 13. Again olefiant gas, in flames the professor considered to be due to the enable the observer to read a newspaper at a dis-C, H4, forms napthaline, C10H8, when the vapour presence of dense hydrocarbon vapours. One of the most interesting experiments shown was that tance of two feet from the flame, and this without density augments from 1'! to 64." These are some of sending an electric spark first through air under any reflecting surface behind the flamo. Examined of the dense hydrocarbons which are known to ordinary pressure, and then through air under by the spectroscope, the spoctrum of this flame is exist in a gas flåme, but there are doubtless others doubled pressure. The result was that the light bright and perfectly continuous from rod to violet. still moro denso ; pitch, for instance, must consist of the spark due to combustion of the air was very carbonic oxide in oxygen becomes much more carbons, for it distils over from the retorts in the

With a higher initial luminosity the flame of of the condensed vapours of such heavy hydromuch increased. The spark was sent also through luminous at a pressuro of ten atmospheres than a process of gas making. Candle flames are similarly many other gaseous and vapourized substances, flame of hydrogen of the samo size and burning constituted. The direct dependence of the luminosity showing most conclusively that the greater the under the same pressure. The spectrum of car- of gas and candle flames upon atmospheric pressure atomic weight of the bodies the greater was the bonic oxide burning in oxygen under a pressure of also strongly confirms tho view that the light of luminosity of their flames when submitted to com-fourteen atmospheres is very brilliant and perfectly these flam-s is due to incandescent dense vapours, bustion by the electric spark,

continuous. The speaker then proceeded to investigate a

This inquiry cannot be confined to terrestrial number of different flames. He showed that thero If it be true that dense gases emit more light objects. Science seeks alike for law in the meanest are many flames possessing a high degree of lumi-than rare ones when ignited, the passage of the and grandest objects of creat on. From questioning nosity which cannot possibly contain solid particles. electric spark through different gases ought to a candle she addresses herself to suns, stars, nebulæ, Thus the flame of metallic arsenic burning in produce an amount of light varying with the and comets; the same consideratione which have oxygen emits a remarkably intense white light, density of the gas; and the speaker showed that just been applied to gas and candle flames are and as metallic arsenic volatilizes at 180deg. Cent., 1 electric sparks passed as nearly as possible, under equally pertinent to these great cosmical sources and its products of combustion, arsenious anhydride, similar conditions, through hydrogen, oxygen,

of light. at 218deg. Cent., whilst the temperature of incan-chlorine, and sulphurous anhydride, emit light, the descence in solids is at least 500deg. Cent., it is intensity of which is very slight in the case of

SHAW AND JUSTICE'S PATENT DEAD obviously impossible here to assume the presence hydrogen, considerable in that of oxygen, and very

STROKE POWER HAMMER. * of ignited solid particles in the flame. Again, if great in the case of chlorine and sulphurous anhycarbonic disulphide vapour be made to burn in dride. On passing a stream of induction sparks By MR. JAMES FLETCHER, JUN., OF MANCHESTER. oxygen, or oxygen in carbonic disulphide vapour, through the gas standing over liquefied sulphurous TN introducing this improved power hammer, the an almost insupportably brilliant light is the result; anhydride in a strong tube at the ordinary tempera writer thinks it would not be out of place to now fuliginous matter is never present in any part ture, when a pressure of about three atmosphores observe that many and varied attempts have been of this dame, and the boiling point of sulphur was exorted by the gas, a very brilliant light was made at different times to produce a power ham(440deg. Cent.) is below the temperature of incan- obtained. A stream of induction sparks was passed mer that can be driven by a strap from a line shaft ; descence, so that the assumption of solid particles through air confined in a glass tube connected with and still possess all the essential qualities of a in the flame is here also inadmissible. If the last a condensing syringe, and tho pressure of the air steam hammer, viz., to strike light or heavy blows experiment be varied by the substitution of nitric being then augmented to two or three atmospheres. (one or more at a time), to run quick or slow, to oxide gas for oxygen, the result is still the same ; a very marked increase in the luminosity of the be perfectly under control, and capable of being and the dazzling light produced by the combustion sparks was observed, whilst on allowing the con- stopped instantaneously. of these compounds is also so rich in the more re-densed air to escape, the same phenomena were

The oldest form of power hammers, the helve frangible rays that it has been employed in taking observed in the reverse order.

and tilt, havo proved themselves, and are still coninstantaneous photographs and for exhibiting the Way's mercurial light was also exhibited as an sidered, extremely useful for a variety of purposes, phenomena of Auorescence. Lastly, amongst the instance of intense light produced by the ignition especially for shingling, forging blooms, round chemical reactions celebrated for the production of of the heavy vapour of mercury.

shafting, railway axles, and tilting steel; but as dazzling light, there are few which surpass the The gas and vapours just mentioned have the their speed, or weight of blow, cannot be altered, active combustion of phosphorus in oxygen. Now following relative densities :- Hydrogen, 1; air, they are ill adapted for heavy forgings, or general phosphoric anhydride, the product of this combus- 14:5; oxygen, 16; sulphurous anhydride, 32; smithwork, and consequently for these purposes tion, is volatile at a red heat, † and it is therefore chlorine, 35:5; mercury, 100; phosphoric anby- have been superseded by the steam hammer. dride, 71 or 142.

Many spring and atmospheric hammers bave been * Read before the British Association.

The feeble light emitted by phosphorus when made mostly with a cam motion to compress the Davy mentions this fact in connection with his view burning in chlorine seems, at first sight, to be an spring or air contained in the cylinder, but as these of the source of luminosity in flames, and endeavours to exception to the law just indicated, for the density arrangements absorbed a great amount of power, "Since this paper has been written, I have found that of the product of combustion (phosphorus tri- the steam hamıner being much more manageable, phosphoric acid volatilizes slowly at a strong red heat, but chloride) 68.7, would lead us to anticipate the evolu- and having as few or less working parts to get out under moderate pressure it bears a white heat, and in a tion of considerable light. But it must be borne in of order, has been used in preference, even when it flame so intense as that of phosphorus the elastic force mind that the luminosity of a Alamo depends also must produce the effect of compression."—"Davy's Works," vol. vi., p. 48.

upon its temperature, and it can be shown that the * Read before the Manchester Institution of Engineers.

SH AW AND JUSTICE'S PATENT D E A D STROKE POWER

HAMMER.

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has been necessary to place it in a very incon- W is provided with a quadrant and lock handle Y lover is lowered it relieves the cam from the brake venient locality, on account of being near a boiler. to fix it in any desired position.

and presses the pulloy against the strap, thus The hammer of which the writer is about to give A A is a lever for starting, stopping, or varying tightening it upon the driving pulley and setting a description is the invention of Messrs. Shaw and the speed, and has a cam B B forged upon its boss the hammer in motion, the pressure put upon the Justice, of Philadelphia, and is one of those peculiar which, when the lever A A is depresse d, raises strap by the pulley regulating the speed of the and simple inventions, so many of which have the brake C C against the fly-wheel F. This hammer by allowing the strap to slip when runemanated from our cousins across the Atlantic. lover is koyed on the shaft DD which passes ning slowly, and tightening it as the speed is to be Its principal feature is the application of a semi- through the framo, and has on its other end a cam increased. circular spring betwoen the crank pin and the tup E E, which is for the purpose of raising or lower The writer will now draw your attention to the or upper moving hammer, to which it is attached ing the lever F F and weight G G, which is fixed principal features of this hammer, namely, the by a leather band. Diagrams 1 and 2 are front and upon the stud H H, having a steel tail pin on a action of the spring. When the hammer is at rest, side elevations of the hammer. A is the driving joint at its upper end, and is for the purpose of and the crank pin on the bottom centre, it will be pulley, driven from any line or countershaft most pressing the friction disc C against the friction observed from the model and diagrams 1 and 2 convenient; B is the shaft ; C is a circular friction pulley D. The two cams being keyed on the shaft exhibited, that the face of the upper hammer does disc, or plate of iron truly turned on its face, and D D are simultaneous in their action. Thus, when not touch the anvil block. In the model, the top supported by brackets projecting from the main the lever A A is raised the cam B B relieves the of which is only 2lb. weight, there is a clear space casting of the hammer ; D is a friction pulley' brake C C from the fly-wheel F; at the same time of nearly gin., and in one of lịcwt. there is 3in. to covered with leather, uprn which the disc c is the cam E E lets the lever F F and weight GG 3 in. When the hammer is running the moment pressed when the hammer is in action ; E is the down, the tail-pin pressing upon the hardened the crank pin passes the bottom centre it plucks shaft carrying the fly crank wheel F, and also steel end of the shaft B, thus putting the hammer or snatches at the tup through the spring and revolves in bearings cast in the main framo; G is in motion by the contact of the friction wheels; loather band, but the tup being in a state of rest the crank pin, which raises and lowers the tup; and whon the lover A A is depressed the cam B B cannot necessarily be so suddenly raised as it H is a connecting rod made in two parts, and puts on the brake, whilst the cam E E raises the would were it directly attached by a connecting capable of being lengthened and shortened by lever F F and the weight G G, and releases the rod to the crank pin ; but the spring giving way, means of the tube I and set screw K. The lower pressure from the friction disc or pulleys, allow- as will be understood, it moves slowly at first, and part of the connecting rod H is attached to the ing the brake to arrest the motion of the hammer gradually increases its upward speed by the comspring by means of the cramp plate L, and two instantaneously when in any position. The cam bined action of the spring and crank pin, the bolts which grip the centre or thickest part of the EE is made flat on its upper end, as shown on former of which is endeavouring to stretch or pull spring M. This spring is of semicircular form, and diagram 1, fig. 2, so that the action of the lever the leather band in a straight line. By the time consists of a number of steel platos put together in F F and weight G G holds the lever A A up when the crank pin has arrived at the top contro the the same manner as a coach spring. The ends of the hammer is not in action, and dispenses with a spring has extended itself, but the tup having the outside or upper plate, projecting a little below quadrant and catch or other fastenings. By only gathered so much impetus declines to stop, and the other platos of the spring, are formed in the partially raising the lover A A the weight upon still going upwards it is met by the downward shape of a hook, and fitted with brass bushes N, the friction disc can be regulated so as to run at action of the crank pin, which again collapses the through which the pin 0 passes, connecting the any speed required or give the roquisite weight of spring, when the tup, assisted by the spring, crank links P to the brass bushes Q, round which the blow.

pin, and its own weight, comes down with great strap R is stretched.

Another method of varying the speed and blow force. The tup, when going at full speed, traThe tup S is composed of Bessemer steel, having has been extensively used in America with much verses about double the throw of the crank. In a slot in the upper end, through which the leather success. In this case it is necessary that the consequence of the spring being placed between band R passes.

In the bottom there is a dove- driving pulley should be immediately over that the crank pin and the hammer the weight comes tailed slot, so that different shapes or forms of on the hammer, making it sometimes necessary to gently upon the crank pin, causing very little swages or dies may be introduced. The anvil employ a countershaft. The pulley is made with strain. The connecting rod H being in two parts, block T is koyed in a groove planed in the main a flange on each side to prevent the strap, which through which all the strain passes, is held togeframe, the bottom or front part of which is cast is left so long and slack that when the hammer is ther by only one steel scrow. The weight of the solid, forming an anvil block to resist the action not in motion it runs loosely between the flanges blow is entirely dependent upon the speed at of the hammer. The levers W X (the latter hav- without touching the body of the pulley. The which the hammer runs, striking a light blow ing brass clips at the upper ends working in a same brake motion and stopping and starting lover when running slowly and a heavy one when rungroove turned in the boss of the friction pulley D) are employed as previously described, but instead ning quickly. are for the purpose of bringing it nearer or further of friction pulleys and the weight, lever, and cam This hammer possesses a great many advantages from the centre of the friction dise C, so as to alter motion a lever is fixed on the back of the framo, 'orer all others. It can be fixed in any desired the maximum speed of the hammer. The lover carrying a guide or pressure pulley. When the situntion whereror there is a driving shait, and is

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a steam hammer would drive, by means of an en- / the " Stier" to Holland, Lieutenant Bogearts being has boen only partially carried out, but partially

independent of boilers. " It takes less power than Captain Hugenholtz, of the Dutch Royal Navy, who CRYSTAL PALACE SPECIAL EXHIBITION. any other hammer. The writer has no doubt that has come round in the "Buffel," another armour-plated

THE laudable intention of the managers of the gino, at least three of these hammers, each doing “Stier" outside the harbour to try the guns, slides, &c., only from no shortcoming on their part. The in

charge. Afterwards, Captain Hugenholtz took the the same amount of work. It has very fow work and the turret gear, all of which were in charge of, tention was to afford space for a display of the ing parts, is not at all liable to get out of order, and worked by, the officers and crew of the ship, and articles-English products, manufacturos, and and the cost in repairs is merely nominal. There several rounds were fired, first from each gun singly, othors--which had been exhibited at the Paris aro no cylinder, valve rods, or joints ; no packing and afterwards both guns simultaneously, they being Exposition of last year. The chief difficulty in required, or any attention after working hours; the loaded with the full charge of 431b. of powder, and carrying out this intention has arisen from the bearings are brass, and made very long. It is so filled shell weighing 3001b. The turret was worked fact that the articles exhibited, and especially those simple to work and easy to control that no instruc- entirely by the steam gear whilst the firing was tions are necessary, and any boy in the smithy can going on, and it was found thoroughly under control, which took prizes, have been disposed of, and the manage it. It is self-contained, and requires but a coinplete revolution being made in thirty-five owners are indisposed to incur the trouble and little foundation. For tilting steel it will be found seconds; and all the gun gear worked very satis- cost of producing duplicates. The series of exan excellent substitute for ordinary tilt hammers factorily. Captain C. P. Coles, R.N., O.B., was on hibitions, notwithstanding this bindrance, has been with wooden shafts, which are constantly break the arrangements of the ship. After the trial of her be expected to be very attractivo, if well supplied

board, and expressed himself well pleased with all very interesting, and the two that still remain may ing. In this case it may be further simplified by guns, the “Stier" returned Birkenhead dock to by exhibitors, The first of these, which combeing driven by a pair of cone pulleys, and thrown complete her coaling, &c., and will leave for Holland mences on the 26th current, will include agriculout of gear by means of a clutch box or friction in a few days.

tural, chemical, and farinaceous products; perclutch. By driving it this way, the speed can be The more we see of these Dutch monitors the more fumery, condiments, vegetables, and fruits. The varied according to the size of steel required to convinced are we that sooner or later pur Govern- exhibition following, which will be the last of the be tilted, and the hammer would run at a regular ment will be compelled to adopt similar ones for speed. The diagrams 1 and 2 represent a ljcwt. coast defence purposes in preference to forts. They series, ought to be the best, including, as it hammer which the writer has had at work for some easily mancu vred, and in the brierent possible space and lighting, sewing, telegraphy, agriculture, time with the most gratifying results. It is quite of time are able to concentrate on any given point a chemistry, mining and metallurgy, civil engineeradequate to work 4.in. steel, round or squaro, and most destructivo fire, remaining themselves nearly ing, and machines and apparatus in general its maximum speed is 200 blows per minute.

impervious to shot and shell. The gunners in the very wide designation. The exhibition now on turrets suffer no inconvenience whatever from the foot is of “portable woapons," and, although the explosion, and what little smoke there is rapidly exhibitors are not numorous, is interesting in the

clears off through the gratings. Such a vessel as the variety of broech-loading riflos exhibited. A single THE DUTCH MONITOR “DE STIER." WF E have from time to time noticed in our columns Mersey, and with impunity do millions worth of firm, Messrs. E. M. Reilly and Co., show almost the several ironclad rams and monitors which damage in a very short time.--"Liverpool Albion."

erery variety known, including the Snider patont the Dutch Government has been building in this

adopted by the English Government, the French country for the defence of their coasts and harbours.

Chassepot, the Belgian Albini, the Austrian The last of these, "De Stier," has just been completed

A NOVEL RAILWAY.

Sedehl, the patents of Reeves, Sharp, Prince, Her dimensions are as follows :-Length, 205ft. ; breadth, A lington, 0. is now in romuirsofo Mconstruction: ley Richards, Green Brothers, Spencer Repeater, 38ft.; depth 19ft. ; tonnage, 1,326 tons. armour-plated with fin, plates from 3£ft. below the level of the sea, and the road when complete will be the revolving breech, solf-capping, and circular

She is The station at the starting point is 2,700ft. above the Fosbory, and others. There are also specimens of water-line up to the gunwale, for the greater part of two miles and 260 rode long, rising in that distance hammer breech-loaders, of the Reilly-Comblain her length, the plates tapering slightly towards the 3,600ft. to the Tip-Top-house, which is 6,800ft. -an improvement on the rifles of the various ends. The armour rests on a backing of 10in. teak, above the level of the sea. and this again on an inner skin of lin. supported by track is 1,280ft. to the mile, but in some parts of the elephants, tigers, deer, wild fowl, rooks, and rab

The average grade of the governments--and of rifles and guns for shooting the framing of the ship. Her turret, which is cylin, line the grade is increased to 1,760ft, to the mile, or bits; with air guns, walking-stick guns, revolvers, drical, and constructed on Captain Cowper Coles' one foot in every three. On this portion of the road, and divers other instruments for offence and deprinciple, is protected all round by armour-plating, workmen, notwithstanding the sharp spikes in their fence. This exhibition remains open till the 23rd which in no place is in thickness less than Sin., in- shoes to prevent them from falling, could only build creased to 1lin. round the ports, the plates resting 25ft. per day. The track consists of three rails, the

current. upon a teak backing of 13 inches, with an inner iron one in the middle being of wrought iron, with cogs skin of lin. The turret carries two 300-pounder riflo guns, having a range of fire from 10deg. of the line The train consists of the locomotive with a tender

or pins corresponding to cogs in the driving wheel. COMPOUND ENGINE AT THE LONDON of keel forward and 6deg. aft, so that she can in and one passenger car. The locomotive of 35-horse

JUTE WORKS. rapid succession deliver her fire at almost all points; power is built with its boiler suspended, so that it is THE engine which forms the subject of our while the facility with which her twin screws enable always level ; it weighs four tons, and pushes up the

THErgos ingravings fons web presents many her to turn will make her very handy in action. Her train before it. The driving wheel is 18in. in dia- points worthy of notice. port sills are arranged at a height of 6ft. bin, above meter, Thero is a similar cog wheel on the tender, Canal Basin Boundry Company, Glasgow, for the

It was made by the water. The turret, in addition to the usual apparatus and another on the passenger car, each strong for working by hand, is fitted with steam gear, which enough to hold the entire train. Frietion rollers, London Jute Company, Ponder's End, is under the control of the captain of the turret, the running under the edges of the middle rail, hold the gino, taken as a whole, has four cylinders, or, starting gear being led up to the sighting platform, train down upon the track. The central rail pro- more strictly speaking, will have fou when comOn the main deck is a shot-proof pilot tower, and a jects about lin. on each side beyond the beam on pleted, two being found sufficient for the prepoop and forecastle fitted with supplementary cabins, which it is laid. To the locomotive there are attached sent to drive the mill, although the complete bedin addition toexcellent accommodation for officers and one steam brake and one hand brake, either of which plate has been put down. As the engines are crew below the main deck, under the protection of can stop the train in a moment, and, in ascending, a the armour. By the arrangement of hatchways: strong wrought-iron dog works into the cogs of tho will suffice to speak of a single pair of cylinders

exact duplicates of each other in every respect, it which are carried above the main deck, excellent driving wheel to prevent " back sliding." In descendlight and ventilation for the below-deck cabins are ing, the steam is shut off, and the engine is eased

here. secured ; and ample accommodation is reserved below down by using compressed air. An experimental

Each engine consists, then, of a high and lowthe water-line, for magazines, store-rooms, coal. trip was recently made on the part of the road already pressure cylinder ; the diameter of the former is bunkers, &c. The ram-stem is of iron and of great completed, and the locomotive is described as work? | 24in., of the latter 36in., the stroke of both being strength, projecting about five foet at such a depth ing with a steady motion. There was no jarring or

5ft. The cylinders, throttle-valvo chest, and under the water as to enable her to strike an enemy's rocking, but merely a slight trembling, like that of jackets, are cast in one piece, and, from personal ship below her armour-plating. This formidable a steamer under the stroke of its engines. The inspection, we can pronounce them a thoroughly weapon of offence is built solid into her framework, ascent from the starting point to the second station, good job. The cylinder covers are also jacketed, and is so constructed as to resist the shock of the 5,500ft. above the level of the sea, was accomplished all the spaces being supplied with steam direct collision. Her machinery, which has been made at in 1 hour and 20 minutes, including'two stoppagesffor from the boiler by a distinct pipe. There is but the same works, consists of two pairs of surface-con- water. The descent occupied 38 minutes. A passen- one connecting rod for each pair of pistons, widely densing direct-acting engines, each of 175-horse ger ear holding fifty persons now runs up to the forked at the tail so as to grasp the crosshead as power, giving 350-horse power collectively, and are second station. so arranged as to work to a very high indicated

near the rods as possible, in order to avoid the power, each pair of engines driving a screw under

chance of side strain. The valve chests are arthe counter of about 12ft. diameter. Her boilers are STEAM FIRE-ENGINE FOR BUENOS

ranged on the upper sides of the cylinders, and the fitted with super-heaters, and the machinery generally

AYRES.

valves driven by a single eccentric through the is made in accordance with the new Admiralty specifications for engines of this class. The “Stier" made

THE Western Railway Company of Buenos medium of a rocking shaft, as will be seen at a her official trial trip about ten days since, the Dutch Messrs. Merryweather and Sons, of London, a me- pally takes place in a horizontal enlargement of The vessel was complete in every respect, having dium size steamfiro-engine, of the same pattern as the waste pipo on its way to the air pump, the her guns and ammunition and full amount of coals the "L'Imperatrice," one of the engines for which injection water entering just at the elbow and and stores on board ; her mean draft of water was this firm was awarded the first prize and gold flowing with the uncondensed vapour to the con15ft. 0 in., the displacement on this draft being 2,025 medal at the Paris Exhibition of last year, with a denser, which is not immersed in a tank. The tons. The speed was tested at the measured mile large quantity of hose and reels, so as to enable air pump is actuated by a rocking shaft beneath at the entrance to the Mersey, and six runs at full- the engine to draw water from the river. The the floor of the engine-room; an arm from this boiler power gave a mean speed of 12-458 knots, the engine has a horizontal steam cylinder Sin. dia- shaft also drives the feed pump. The remaining engines making. 92revolutions, and the indicated meter, with 18in. stroke of pistons. It was re- details will be easily gathered from our engraving: horse power being 2,257. Two runs at half boiler cently tried in the presence of the engineer of the We may state that the fly-wheel drives the mill power gave a mean speed of a10:778 knots, with 77 company, and gave very satisfactory results. through the medium of a spur wheel on a shaft tevolutions and 1,234 indicated H.P. The turning Steam of 1001b. pressure was raised from cold lying about the same level as the crank shaft outfound to make a complete circle, at full speed, in 44 water in nine minutes, the engines playing a side the wall of the engine-room, through an aper

We minutes, the diameter of the circle being very small; 14in. stream 170ft. high, and two fin. streams the ture in which the spur wheel comes. the rudder, which is fitted on the balance principle, same height, and a lfin. stream 160ft. high. The have omitted the wheel in our engraving from can be put hard over at full speed by three men. steam pressure was easily maintained with the want of space. The engine runs at a speed of 400ft. Since this trial the "Stier" has been handed over to fire-door open.

per minute.

The en

[subsumed][subsumed][merged small][merged small][graphic]

At the first glance it might be assumed that, it must be borne in mind, first, that a back pres- at each end of the crosshead. It is quite certain owing to the arrangement of the cylinders, an in- sure equal to the positive pressure on the large that no crilence of twisting strain is perceptible jurious tvisting strain would be brought on the piston has to be deducted from the strain on the while the engine is in motion, and engines similar crossheads, but this is not the case. Steam from small piston end of the crosshead, while the much in every respect have been running for five years the small cylinder exhausts directly into the valve- larger area of the low-pressure piston tends still without requiring one farthing of outlay for rebox of the large cylinder by the shortest possible further to bring about an equality. If steam is pair. It is difficult to see by what other arrangeroute ; and although the pressure in the small cut off at about one-third of the stroke of the ment of compound engine as much power can be cylinder is much higher than in the large cylinder, high-pressure piston the strain is about the same provided in a limited space and at a moderate cost,

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