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his fathers many a year before the oc for the second transit. But, alas ! alas! currence of the transit from which he after eight years of weary waiting, a had prepared men to expect so much. little cloud effectually hid the phenomeAt length, in 1761, the looked-for time non from his sight, and Le Gentil had arrived. Now transits, which are of to return to France empty as he left it. very rare occurrence, when they do Poor Le Gentil! for him there is no happen, occur in pairs, at an interval of cross of honour in life, no national only eight years. Thus, when, after monument at death. He is like the anxious waiting, astronomers beheld the poor subaltern who leads the forlorn transit of 1761, they knew that in eight hope, and perishes in an unsuccessful years they should witness another. It
attack. Let us drop a tear to his was probably this circumstance of a memory and that of Green ere we prosecond transit to fall back upon that claim that the stronghold has fallen! rendered the observations of 1761 so The solar system is now measured. little worth. That date being past, and The distance of the sun is now ascertained the occasion lost, the succeeding transit with positive certainty. Seven different of 1769 was all that the world had to base-lines, a host of independent obserrely on for another century. Had this vations, all concur in giving the distance opportunity been again lost, what a dif of the sun from the earth (in round ferent position would our astronomy and numbers) as ninety-five millions of miles. our navigation have been in from that It is a grand era in astronomy. What which they now occupy! Happily, all would Copernicus, what would Tycho Europe was astir. Men were sent out have said? They, worthy men, great north and south, east and west, to make astronomers as they were, never dreamt the whole length and breadth of the that the sun is a tenth part as far away. globe available base - lines. England
England Even Halley, when he proposed this fitted out an expedition to the South most successful problem, laboured under Seas, and placed it under the command the delusion that he was some thirty of Captain Cook. Who has not read millions of miles nearer the sun than he Cook's first voyage? Most of us have actually was. devoured it, every part but the account Well, we have extended our yardof the observation of the transit, the measure to a pretty good length now. real object of the expedition. Possibly As the earth goes round the sun every it would have been otherwise had the year in an orbit nearly circular, the astronomer Green returned to tell his position we shall occupy six months own tale.
But it was not so to be. hence will be just a hundred and ninety His body was consigned to the deep millions of miles from where we now are. during the homeward voyage. But his And we can observe a star from both ends observation was made under favourable of this line, just as we observed a steeple circumstances, and is invaluable. In previously from the two ends of a field. this respect, Green was happier than Our measuring tape for the stars is a some of his fellow - labourers. The hundred and ninety millions of miles. Abbé Chappe erected his observatory Yet, great as this distance is, so inconin California, and died ere his work was ceivably far away are the stars, that all well complete. M. Le Gentil had been the refinements of modern science were sent out to Pondicherry to observe the unable, half a century ago, to deduce previous transit of 1761; but the winds anything about them but this negative and the waves detained him on ship- conclusion—that the nearest of them is board until after the event had taken at least a hundred thousand times as far place. But Le Gentil was a man of from us
as spring is from autumn, or spirit, not easily discouraged. Ac summer from winter-a hundred thoucordingly, he resolved to lessen the sand times a hundred and ninety milchance of a second disappointment, by lions of miles; no star nearer than remaining at Pondicherry until 1769 that! Yon cannot think of such dis
tances as these—the mind is unable to ago, was this negative fact. No star
Dobrizhoffer, the Jesuit nearer than the parallactic unit, as it is missionary, tells us that the Abipones called, of twenty millions of millions of of Paraguay, anongst whom he laboured, miles! Whether any were so near, have no
better mode of expressing or anything approaching the distance, numbers above a score or so, than by nobody could say. At length the questaking up a handful of sand or grass tion of distance was resolved. And and exhibiting it. They had to pass
here occurs one of those singular duplithrough a deal of schooling to learn cations--twins in the births of thought to count up to a thousand. The Pro -with which the history of science fessor at Angers, wishing to exhibit to abounds. The first determination of the his class the relative magnitudes of the distance of a star from the earth was sun and the earth, poured sixteen pecks worked out simultaneously by two men, of wheat on his lecture table. “This,” under circumstances which precluded said he,“ represents the sun, and one the possibility of mutual assistance; and of the grains represents the earth.” the results were presented to the world If we try a similar method, we shall not within a few days of each other. The succeed so well. Let us, however, try. memoir of Bessel, which announced a You have some faint idea of three sensible parallax for 61 Cygni, appeared thousand miles, from having painfully on the 13th of December, 1838. That measured it on the Atlantic, it may be. of Professor Henderson, in which the The thirtieth of an inch, on the other parallax of a Centauri was established, was hand, you can estimate well enough. It read to the Astronomical Society on the is the dot you place over the letter i, as 6th of January, 1839, and had of course
Well, suppose this dot to been in the hands of the Society some represent the distance between Liverpool days previously. There was no desire and New York; then will the actual on the part of either astronomer to distance—three thousand miles-re contest the claims of the other. Many present the interval, nearer than which years subsequently it was my good there is no fixed star. Three thousand fortune to unite with Professor Hendermiles of dots, when each separate dot son in entertaining his illustrious friend, stands for three thousand miles ! Or Bessel ; and it was a gratifying sight to you may help your mind, or cheat witness the warmth of affection with yourself into the belief that you do so, which these two good men welcomed by some such process as the following. each other as fellow-workers in the Light travels with such a velocity, that
They have both gone to it would fly round the earth, at the their rest—Henderson too early for equator, eight times in a second. Yet science ; Bessel at an advanced
age, and there is no star so near us, but that its full of honours. light occupies more than three years on The stars which Henderson and its journey to the earth. The whole Bessel selected were in one respect starry firmament, seemingly so bright, very unlike. That of Henderson is a may, for ought we know, have been bright star in the southern hemisphere; quenched in everlasting darkness, three that of Bessel is a faint inconspicuous years ago.
Were such a catastrophe star in the northern. But the stars conceivable, the lamps of heaven would have one thing in common-both have go out, one by one, to mortal eyes, large proper motions. They are not year after year, and century after century, fixed stars, in the strict sense of the until, some two thousand years hence, word ; they move on by a few seconds the faint light of stars of the sixth and annually. And this circumstance of a seventh magnitude would alone hold on proper motion was an argument in the its journey.
minds of the astronomers, that those All that was known about the dis stars are in close proximity to our tances of the stars thirty or forty years system. This fact, and not their size,
was the ground on which they were The conclusion may be stated in a selected. Professor Henderson com single sentence. The star selected by menced his calculations with a different Henderson is only a little beyond the object, and only diverted them into the parallactic unit (twenty millions of channel of distance when he ascertained millions of miles); that selected by the amount of proper motion which the Bessel is about three times as far away. star has.
His observations were not Other stars have been reached, but undertaken with a view to this question; these two are the nearest known. With they were ordinary meridian observa a trembling and uncertain hand, astrotions. And it is not to be wondered at nomers have stretched out their line that astronomers were very cautious in to one or two stars ten times as far admitting results so obtained, when it away as the farthest of these. But the is considered that observations of this great host of heaven lie incalculably kind are beset with such numerous farther back. Shall we
ever reach sources of error, in refraction, aberration, them? Judging from present appearand the like. The method adopted by ances, we are compelled to answer in Bessel, on the other hand, obviates those the negative. The stars, as we gaze sources of error. It has some analogy into the sky, seem to defy us.
For to the method of obtaining the distance what do we see there? Close around of the run by means of a transit of us we see bright lamps pretty equally Venus, inasmuch as the observations are distributed over the vault of heaven. not those of the absolute position of one They twinkle and dance before us, as body, but of the relative positions of two. though conscious of the close proximity The basis on which the operations are of our gaze.
But let us look again. conducted is this :- Certain stars are so Clasping the whole vault of heaven, we nearly in the same direction in the see a belt of faint light, some twelve deheavens as not to be easily separated. grees in breadth. This is the milky way, Some of these are in reality double the galactic circle. To the ancients, it twin stars revolving about each other was part of the milk which washed the at any rate, physically connected. Others purple stains from the lily; to the have no such connexion; and it is argued moderns, it is the universe itself-the that, in certain cases, the smaller of the stupendous whole, of which the brighter two is likely to be at an enormous dis stars are but the portions which lie tance behind the other. When such is nearest to this little spot of earth. You actually the case, there will be a change may understand this if you bear in mind of the relative positions of the two as that the spherical appearance of the viewed from different parts of the earth's heavens is a necessary consequence of orbit, and the amount of that change vast and unknown distance. There is will depend on the proximity of the no reality in this appearance. The nearer star to our system, in precisely the arrangement of the stars is somewhat same way as a tree will shift its place like an extended sheet of cardboard, of more or less rapidly, with respect to a small thickness. Or, rather, you should distant hill, as the spectator is carried imagine a vast plain planted with orange along in his journey.
It is on stars so trees, all loaded with yellow fruit. circumstanced that observations with the These oranges in countless myriads are view of detecting a parallax were in the stars. We are situated near the stituted by Bessel. No absolute measures
centre of this grove. Our sun is a of position of either star are required ; small orange; the earth and the planets simply the relative distances and direc are tiny buds grouped around it. The tions of the one with respect to the neighbouring branches are thinly supother. Thus all sources of error due to plied with fruit, and few fruit-stalks refraction, aberration, and many other bear more than a single orange.
But causes, which equally effect both stars, the grove is of boundless extent. Loukare got rid of.
ing on every side, the eye takes in
myriads of golden balls, extending away What imagination shall wing its flight right and left, until individual oranges
to those still more shadowy groups are no longer distinguishable, except by which constitute the unresolved nebulæ ? the glow of light which they send to The yard-measure is too puny; the the eye. This glow is the milky way. hand of man is too feeble. An angel's Looking upwards, or downwards, from hand must grasp the rod that shall the milky way, there is no such pro mete out the length and breadth of fusion of scattering. Much bright fruit this golden grove. Man has gone up does, indeed, cluster on the upper and through the immensity of space and lower branches; and an unpractised eye strained his line till it will bear no is deceived into the belief that the
Other generations may mount number is infinite. But the
higher, but only to find the vast circles astronomer, armed with proper instru ever widening beyond. The position ments, finds it far otherwise. He can which we have reached is a lofty one; count the stars; he can gauge the but, lofty as it is, future ages shall use heavens; and the conclusion to which it as their point of departure. It is an he will arrive is, that the number ennobling thought to console us amid which the eye takes in diminishes our many failures.
Man rises by the gradually from the galactic circle up aid of that Divine faculty which pertains wards or downwards. And this dimi to him alone of all created beings—the nution is not only regular, but is very faculty of accumulating stores of knowgreat indeed. From such considerations ledge, of working in succession, of as these, conjecture has ripened into acting on intelligence transmitted from conviction, that the solar system is a age to age. The great English philosopart of the milky way ; that the scat pher, Bacon, describes man as the “intered bright stars are those parts of the terpreter of nature.” But this is not same which lie in our immediate neigh- his highest, not his characteristic desigbourhood ; and that the whole group nation ; for, are not the beasts, are not forms a vast, extended, rolling prairie of the birds, are not the very insects stars. The milky way is, therefore, to interpreters of nature? It is as the human apprehension, nothing less than interpreter of man, the interpreter of the uniyerse itself. True, there may be man's records, that man stands disother galactic systems, other prairies, tinguished. Herein reason transcends other orange groves, as far separated instinct, that its gifts are transmissive from ours as the prairies of America are and cumulative. Mind does not stand from the groves of Europe. Some of the supported by the mind which exists remarkable nebulæ seem to hint at the around it, not simply, not mainly. possibility of the thing. On such a There is a higher and a broader support. subject it is premature to speculate. The minds of the great of bygone ages Now, it is only those oranges
that live and work in the breasts of their cluster round us, those which grow on
The old Greeks, I suppose, the same branch with our sun, that we knew this, and embodied it in the fable have succeeded in stretching out our of Athene, the goddess of knowledge, hand to. What arithmetic shall suffice who sprang into existence not as to count the distance of those which lie naked, helpless child, but as a grown-up on the remoter trees of our grove, the being, clad in complete armour, from the faintest groups of the milky way? head of Zeus.
RA VENSHO E.
BY HENRY KINGSLEY, AUTHOR OF
alarmed. William would come someCHAPTER XLIV.
times and sit quietly behind Marston, or Lord Saltire, watching the game.
In ANOTHER MEETING.
short, they were a very quiet pleasant LORD Ascot had been moved into party indeed. South Audley Street, his town house, One night-it was the very night on and Lady Ascot was there nursing him.
which Adelaide had lost her hat in the General Mainwaring was off for Varna.
no whist. Marston But Lord Saltire had been a constant had gone down to Oxford suddenly, visitor, bringing with him very often and William came in to tell them so. Marston, who was, you will remember, Lady Ascot was rather glad, she said, an old friend of Lady Ascot.
for she had a friend coming to tea, who It was not at all an unpleasant house did not play whist; so Lord Saltire and to be in. Lord Ascot was crippled — Lord Ascot sat down to picquet, and he had been seized with paralysis at
William talked to his aunt. Epsom ; and he was ruined. But every “Who is your friend, Maria ?” asked one knew the worst, and felt relieved by Lord Saltire. thinking that things could get no worse “A Mr. Bidder, a minister. He has than worst, and so must get better. written a book on the Revelations, which
In fact, everyone admitted to the you really ought to read, James; it family party about that time remembered
would suit you.” it as a very happy and quiet time indeed. They both laughed. Lord Ascot was their first object, of “ About the seven seals, hey ?” said course; and a more gentle and biddable
Lord Saltire ; " • septem phocæ,' as I invalid than the poor fellow made can remember Machynleth translated it at hardly be conceived. He was passion Eton once. We called him • Vitulina' ever ately fond of reading novels (a most
after. The name stuck to him through reprehensible practice), and
life with some of us. A capital name easily amused. Lord Saltire and he for him, too! His fussy blundering in would play picquet; and every evening this war-business is just like his old there would be three hours of whist, un headlong way of looking out words in til the doctor looked in the last thing, his dictionary. He is an ass, Maria ; and and Lord Ascot was helped to bed.
I will bet fifty pounds that your friend, Marston was always set to play with the minister, is another.” Lord Ascot, because Lord Saltire and “How can you know? at all events, Lady Ascot would not play against one the man he brings with him is none." another. Lord Saltire was, of course, one
« Another minister ?” of the best players in Europe ; and I “Yes, a Moravian missionary from really believe that Lady Ascot was not Australia.” the worst by any means.
I can see the “ Then certainly another ass, or he party now! I can see Lady Ascot lay- would have gone as missionary to a less ing down a card, and looking at the abominably detestable hole. They were same time at her partner, to call his all burnt into the sea there the other day. attention to her lead. And I can see Immediately after which the rivers rose Lord Saltire take out his snuff-box seventy feet, and drowned the rest of thereat, as if he were puzzled, but not then.'