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(From the French of Philippe Théolier.)
Didst thou linger in the country of our dreams,
When I was forced from thee and that dear land ?
Where every eve our future course we planned ?
Where happy hours we shared, dost ever sigh
Ah! they were bright, those dreams of days gone by!
Call back those years to mind: when, children both,
Our life ran on, all shadowed o'er with joy!
Shone through our heart in gleams without alloy !
Each feathered songster paused to drink thy lay:
How fresh they were, those flowers of childhood's day!
Oft through the forest's dim mysterious shade,
Tracking each bidden path, we loved to trip;
Thy dimpled dainty feet were wont to dip;
As 'neath the friendly boughs they sheltering lie:
METEORS AND SHOOTING-STARS.
BY RICHARD PROCTOR, B. A., F.R.S.
AMONGST the many surprising discoveries economy of nature as a rain-drop or a which have of late years rewarded the la- snow-flake-indicates the close of a career bors of astronomers, none perhaps are during which the mighty orbits of Jupiter more remarkable than those which relate and Saturn have been encircled, nay, often to the phenomena- 1-once thought so in the utmost limits of the known planetary significant-presented by “falling stars.' scheme overpassed by uncounted millions Ten years ago, though the thoughtful of miles. astronomer had become convinced that Even now, when the nature of these these objects really belong to the domain objects has been revealed to us, and some of astronomy, doubt still rested on that insight afforded us into the part which they theory of their nature. Men could perform in the economy of nature, it seems scarcely believe that the vast depths difficult to realize the full significance of amidst which the planets pursue their ascertained facts. The very aspect of the career around the Sun are the home of planetary scheme seems changed as countless bodies which rush with even more contemplate the results of recent labors than planetary velocity upon wide orbits in meteoric astronomy.
Kepler and round the solar orb. It seemed incredible Copernicus, could they revisit this world, that each of those faintly gleaming lights, and, mixing as of old among astronomers, passing with silent swoop across a star- inform themselves respecting the theories group-leaving no trace of their existence now upheld, would scarcely recognize the and seemingly as little important in the scheme of the universe so unfolded to their
view. Truly the harmony of the plane- It seems to me abundantly clear that tary system recognized by Kepler seems the contrary is the case. We have only strangely marred, ' as sweet bells jangled two means of judging of the richness out of tune and harsh' by these eccentric and importance of a meteor-system. One meteor orbits. These crowds of inde- is the observation of its apparent richness, pendent orbs, rushing disorderly around and the individual magnitude of the methe Sun, in no sort resemble the ' obedient teors belonging to it.
But the apparent family,' which Copernicus recognized in richness alone can be but a deceptive inthe solar system.
dication of the real richness of a stream of Many times during the last few years meteors. If we were sure that the Earth the history of those discoveries and re- plunged through the heart of each meteorsearches by which meteoric astronomy stream, we could indeed learn something has reached its present position has been in this way, precisely as we might compare recounted. It is not my purpose to de- the relative thicknesses of different cords scribes these matters anew. But it has by the resistance experienced in piercing seemed to me that the approach of the them through the middle with a needle. Earth towards that great stream of meteors But we have no assurance whatever that to which the November shower is due, the Earth passes through the heart of a will render a brief discussion of some of single meteor-system.
It may be that if the most striking facts lately discovered she did the results would not be altogether not unacceptable even to many who look pleasing or satisfactory to her inhabitants, on astronomy from afar off, and regard and certainly the chances are enormously astronomers somewhat as Indians regard against her doing so. The minuteness of their medicine-men.
the space actually passed through by the We may take the November shooting- Earth on her course round the Sun-at stars as typical of a class of meteor-sys- least the minuteness of this space by comtems, which must undoubtedly be very parison with the dimensions of the solar numerous. It is true that as the Earth system—is not commonly appreciated. If sweeps on her wide orbit round the Sun
we represent the sun as a globe about as she encounters few such streams as that large as a billiard-ball, the space along to which the November meteors belong. which the Earth pursues her course would As she reaches certain critical parts of that be represented by a thread or twine formorbit she is exposed, indeed, year after ing a circle nearly eight yards in diameter. year, to a species of cannonade of greater Now conceiving such a circle, and regardor less intensity; and occasionally the ing the meteor-systems as oval hoops round weight of metal with which she is thus as- the central ball, which happen to cross saulted is far heavier than any which she this fine circular thread, it is scarcely conhas to encounter during the second week ceivable that in one case out of a thouin November. But for a systematic and sand the thread would pass centrally continuous downpour of missiles the No. through the substance of one of the hoops. vember stream is unsurpassed by any, ex- We can therefore infer little or nothing cept perhaps the August meteor-system. from the apparent richness of meteorIf we could count the total number of streams as to their real importance, bemeteors which have been rained upon the cause we do not know whether our Earth Earth during the past five or six centuries, passes through the core of any particular and assign each individual meteor to its stream or merely grazes its surface. proper system, I have very little doubt that We may learn something from the avethe November stream would be found to rage dimensions of the meteors belonghave supplied a full tenth part, though the ing to a system, though our inferences total number of systems which our Earth may not be altogether reliable. So far as encounters is known to exceed one hun- this point is concerned, the November dred.
meteors would seem relatively inferior to This being the case, it may be worth many others. They are too small to pene. inquiring whether the November system is trate through the atmosphere, so as to in reality richer than the others—whether reach the surface of the Earth, not one there is anything in what we know about instance being on record of a November this stream to lead us to suppose that it is meteor affording any tangible evidence of more important than the rest.
its existence; and from the researches of Professor Alexander Herschel, it would it has been (beyond all question) associated, seem that on the average the November is so faint and small that it has never yet meteors weigh but a few grains each. been discerned by the unaided eye. In a When we compare this with the fact that powerful telescope it appears but as a faint bodies belonging to other systems have nebulous light, nor is it even adorned with been found to weigh many pounds, some the ordinary appendage of respectable even being several tons in weight, the re- comets—a tail. Taken apart from the lative insignificance of the November significance of what we know respecting system in this respect will be clearly it, this comet is certainly one of the least recognized.
striking objects which the telescope has But there is a second method by which ever revealed to astronomers. in comparatively recent times it has be- On the other hand, the August meteors come possible to guess at the importance are associated with a comet of distinction of different meteor-systems.
— with a comet which has been watched The surprising discovery that many by many millions of human beings as the meteor-systems are associated with comets harbinger of some uncanny event, and has not hitherto been fully interpreted. has been recognized even by men of We know quite certainly that along the science as worthy of respectful attention. orbits of certain comets there travel Indeed, if its approach had been antimyriads of tiny bodies-meteors—which cipated and its course known, but the we assume to be solid. But what con- hour of its arrival uncertain, it is far from nection there may be between the gaseous unlikely that men of science would have comet and its solid attendants, whether looked forward with some dread to the the comet gave birth to the meteors, or possible effects of its arrival. For it was whether the meteors in some way or other one of those comets—few, indeed among combined along one part of the system to the larger sort-whose track crosses the form the comet, has not hitherto been ex- Earth's, and had it come but a few months plained. It may be regarded indeed as earlier or later, we should by this time one of the most mysterious facts ever have had the means of answering that discovered by astronomers that any asso- long-vexed question whether the Earth ciation whatever should exist between would suffer injury were she to come into bodies seemingly so different in their nature direct collision with a large comet. So as comets and meteors. But there the re- that if we judged of the relative importance lation is, let us make of it what we will of the August and November meteorNo doubt rests on the reality of the systems by a reference to the relative discovery; no one who understands the importance of their comet companions, we nature of the evidence can believe for a should undoubtedly conclude that the moment that the relationship is merely August meteors are far the most imapparent, and the coincidence of orbits portant. It would follow from this that, merely accidental. So that, in fact, it has since the November meteor-system procome to be gravely questioned whether duces showers quite as striking as any seen any meteor-system exists without in August, we do not in reality see the full cometic nucleus, and whether any comet splendor of the August meteors, but, exists without a meteoric train.
passing only through its edge, recognize Be this, however, as it may, we are at but the scattered outliers of the system. least justified in comparing together such But this being so, those who remember meteor-systems as are known to be asso- the magnificent display of November ciated with comets, and inferring the metors in 1866, will consider with amazeprobable importance of such meteor- ment how grand the August system must systems from the observed brilliancy of be if it is really capable of supplying a their comet-chief.
far more splendid shower. We remember Now, judging in this way, we should be how the stars seemed to fall continuously, led to conclude that the November stream, so that at every instant (at least during a notwithstanding the wonderful magnifi- certain interval) shooting-stars could be cence of the star-showers observed when seen in some part or other of the heavens. the Earth passes through the system, is in And we know, also, from the accounts of reality one of the least important of the Humboldt and Bonpland that, sixty years meteor-systems. The comet with which before, there had been a yet grander dis
play. If a meteor-system associated with actual contact with her that her inhabiso insignificant a comet as that of 1866 tants can have direct cognizance of the can produce these wonderful showers, how existence of such bodies. Let us follow inconceivably magnificent would be the out this illustration. Suppose a blind scene if the Earth passed through the man walked a distance of ten miles, and heart of the August meteor-system, asso- during the whole continuance of his walk ciated as that system is with a comet of felt rain falling upon him. Would it be a considerable splendor!
reasonable conclusion on his part that the But similar considerations may fairly rain had fallen precisely along the track he be extended to all the meteor-systems which had followed, and nowhere else? Would the Earth encounters. These are counted he not conclude, on the contrary, that the by the hundred, and though most of them extent of country on which the shower had seem insignificant compared with the fallen extended probably, at least, as far August and November systems, yet we from right to left as he had found it to have seen that no opinion can hence be extend in the direction of his walk ? Most formed of their real importance. Some of assuredly he would not conclude that a them may as far exceed the August system narrow strip, ten miles long and perhaps a in importance as that system probably yard wide, had been rained upon, but exceeds the November system. Nay, we rather an area several miles wide. In have two excellent reasons for feeling some other words, he would conclude that, indegree of assurance in this respect; for stead of an area of a mere fraction of a one of these less noted systems has been mile in extent, a range of forty or fifty associated with the comet of 1861-an square miles, at least, had been visited by object not inferior in splendor to Donati's the shower. comet—and some of the recognized sys- It is equally reasonable to conclude tems occasionally sent us visitors in the that the track of the Earth is not the only form of massive aërolites, compared with part of the Sun's domain which is crossed which the tiny bodies forming the August by meteor-systems. There is no conceivand November meteors are as small shot able reason why that particular hoop of to the Whitworth bolts. Startling, how- space should be visited rather than regions ever, as are the considerations thus sug- lying around it. And precisely as our gested, it is when we pass in imagination illustrative blind man, had he stepped to beyond the confines of the Earth's orbit the right or to the left of his actual path, that the true significance of what we know would have been visited by other rain-drops respecting meteors and meteor-systems than those which actually fell upon him, so becomes apparent.
we may reasonably conclude that if our We have seen that our Earth really Earth's orbit were changed so that she visits but a minute proportion of the solar travelled a few millions of miles further domain. The space actually traversed by from or nearer to the Sun than she actually our globe as it circuits round the Sun, does, then she would encounter meteorthough enormous compared with any of systems altogether different from those our ordinary estimates of size—nay, though which now assail her with a shower of exceeding fiftyfold the volume of the Sun “pocket planets.' To come to the point -is yet but the minutest fraction of that for which I have been making all along,vast sphere over which the Sun exerts the whole of the solar domain is alive with supreme sway.
meteors. This is the legitimate conclusion Now, since the meteors are not indi- from the evidence acquired during the vidually discernible save when they enter last few years. So long as it was thought the Earth's atmosphere, all our direct in- that the meteor-systems are nearly circuformation respecting the condition of the lar, there was an escape from this startling interplanetary spaces is derived from the conclusion. It was conceivable that the actual contact of the Earth with bodies meteor-systems might affect the neighborbelonging to those spaces. We obtain hood of the Earth's orbit, much as the our information respecting the planets asteroidal family affects the space lying through their visibility, but as respects the between the orbits of Mars and Jupiter. meteors our Earth may be compared to a
But So as Adams and Leverrier, blind man in a shower. It is only when Schiaparelli, Tempel, and the rest, had the meteors or meteor-systems come into made it abundantly evident that the me
New Series.-VOL. XVI., No. 5
teors travel in very eccentric orbits, there London, and concluding that just that remained no escape from the conclusion number and no more had fallen on the that the intersection of these orbits with whole city. the Earth's path is to be regarded as a It is this conclusion which gives so merely accidental circumstance. The great an interest to the researches of Earth has absolutely no power adequate Adams, Leverrier, and others on the Noto force these meteor-systems to cross her vember meteor-system. If we were sure orbit. We could undertand the orbit of that that meteor-system was the only one Jupiter or Saturn being crossed by many of its kind, or had but few fellows, we meteor-systems, because we know that if could attach no great importance to its a family of meteors were passing close by peculiarities. They would have a certain Jupiter on a course which would carry interest
, doubtless, precisely as the discovthe family far away again into space, the ery of an asteroid has a certain interest; mighty attractive force of Jupiter or Saturn but they would involve no results of would (ordinarily) suffice to force the cosmical significance. Under the actual members of that meteor family to come circumstances, what has been proved reclose to the planet before they could speed specting the November meteors opens a again on their course towards the Sun's field of conjecture of almost boundless neighborhood. Whenever such an en- extent. Whence come these uncounted counter as this took place, the meteor millions of bodies, rushing through space family would, for the future (and until with inconceivable velocity? What puragain disturbed by the planet), travel on a pose do they fulfil in the economy of the path crossing or very closely approaching solar system? Do any of them pour the planet's. But the Earth is far too upon the Sun, as has been supposed, a small to influence in this way the motions hail of cosmical material, replenishing his of meteoric families. Those which ap- fires and recuiting his energies? Has the proach her speed onwards with a velocity mighty attractive influence of the Sun, altogether beyond her control, so that, which guides the planets on their wide unless already travelling on a re-entering circuits, this further work to perform, of orbit passing close by the Earth's, they gathering from out of space the material could never be forced by her attraction to by which his own fires are fed? Or do enter on such a track. A body coming these myriads on myriads of cosmical from the stellar depths towards the Sun bodies, with all the vital forces represented could no more be forced by the Earth's by their velocity, subserve no purpose disturbing attraction to follow a closed whatever in the economy of our system? curve round the Sun, than a swiftly-rushing Are they the chips in the great workshop railway train could be caused to leave the .of Nature, the sparks which have flown rails by the attraction of a toy magnet. from the mighty grind-stone, the shreds
Since, then, those meteor-systems which of clay which the giant potters Attraction cross the Earth's orbit are chance visitors, and Repulsion have cast aside as useless ? as it were, not drawn to their present paths by any attraction the Earth can exert, but coming of their own accord This paper was accompanied by the past her track, it follows that there must following note :be for each recognized meteor-system un- Our readers may be desirous of learning counted thousands which are unknown to what are the chances that the display of us because they do not approach the November meteors will this year be worth Earth's track. There is no escape from observing. In 1866, it will be remembered, this conclusion. The laws of probability the great display lasted but a few hours. will not permit us to believe that, out of a Had it occurred either a few hours sooner moderately large number of meteor-systems or a few hours later, we, in England, in no way attracted to the Earth's orbit, should not have witnessed it
. In the a large proportion would traverse that former case we should have been on the particular track in space. To judge the sheltered part of the Earth—to leeward, number of meteor-systems as no greater so to speak, of the meteor storm; in the than the number enccuntered by the latter, though the meteors would have Earth, would be like counting the rain- fallen upon portions of the atmosphere drops which fall upon a window-pane in above our horizon, it would have been full