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too small; the astronomers of Milan gave creased. On the 11th of January, 1787, the planet a diameter more than twenty he detected two satellites, though several thousand miles too great; and Mayer of days elapsed before he felt justified in anMannheim was even more unfortunate, for nouncing the discovery. At intervals, he assigned to the planet a diameter ex- during the years 1790-1798, he repeated ceeding its actual diameter of thirty-four his observations; and he supposed that he thousand miles, by rather more than fifty had discovered four other satellites. He thousand miles. It will be understood, expresses so much confidence as to the therefore, that Herschel might well leave real existence of these four bodies, that it unattempted the task of comparing the is very difficult for those who appreciate different diameters of the planet. This his skill to understand how he could have task required that he should estimate a been deceived. But he admits that he quantity (the difference between the great- was unable to watch any of these satelest and least diameters) which was small lites through a considerable part of its even by comparison with the errors of his path, or to identify any of them on difformer measurements. ferent nights. All he felt sure about was that certain points of light were seen which did not remain stationary, as would have happened had they been fixed stars. No astronomer, however, has since seen any of these four additional satellites, though Mr. Lassell has discovered two which Herschel could not see (probably owing to their nearness to the body of the planet). As Mr. Lassell has employed a telescope more powerful than Herschel's largest reflector, and has given much attention to the subject, no one has a better right to speak authoritatively on the subject of these additional satellites. Since, therefore, he is very confident that they have no existence, I feel bound to represent that view as the most probable; yet I am unable to pass from the subject without expressing a hope that one of these days new Uranian satellites will be revealed.

But, besides this, a peculiarity in the axial pose of Uranus has to be taken into account. I have spoken of the uprightness of Jupiter's axis with reference to his path; and by this I have intended to indicate the fact that if we regard Jupiter's path as a great level surface, and compare Jupiter to a gigantic top spinning upon that surface, this mighty top spins with a nearly upright axis. In the case of Uranus the state of things is altogether different. The axis of Uranus is so bowed down from uprightness as to be nearly in the level of the planet's path. The result of this is that when Uranus is in one part of his path his northern pole is turned almost directly towards us. At such a time we should be able to detect no sign of polar flattening even though Uranus were shaped like a watch-case. At the opposite part the other pole is as directly turned towards the earth. Only at the parts of his path between these two can any signs of compression be expected to manifest themselves; and Uranus occupies these portions of his path only at intervals of forty-two years.

Herschel would have failed altogether in determining the pose of Uranus but for his discovery that the planet has moons. For the moons of the larger planets travel for the most part near the level of their planet's equator. We can, indeed, only infer this in case of Uranus (for even the best modern measurements cannot be regarded as satisfactorily determining the figure of his globe), but the inference is tolerably safe.

The four known moons travel backwards; that is, they circle in a direction opposed to that in which all the planets of the solar system, and all the moons of Jupiter and Saturn, as well as our own moon, are observed to travel. Much importance has been attached to this peculiarity; but in reality, the paths of the Uranian moons are so strangely situated with respect to the path of Uranus, that the direction in which they travel can hardly be compared with the common direction of the planetary motions. Imagine the path of Uranus to be represented by a very large wooden hoop floating on a sheet of water; then, if a small wooden hoop were so weighted as to float almost For six years Herschel looked in vain upright, with one half out of the water, for Uranian satellites. His largest tel- the position of that hoop would represent escopes, supplemented by his wonderful the position of the path of one of the eyesight and his long practice in detect- planet's satellites. It will be seen at once ing minute points of light, failed to reveal that if we suppose a body to travel round any trace of such bodies. At length he devised a plan by which the light-gathering power of his telescopes was largely in

the former hoop in a certain direction, then a body travelling round the latter hoop could scarcely be said to travel in

lighter materials than the earth. Our earth would outweigh almost exactly six times a globe as large as the earth, but no denser than Uranus. It is to be noticed that in this respect the outer planets resemble the sun, whose density is but about one-fourth that of the earth. It seems

the same direction, whether it circled one | its substance has been ascertained. It way or the other. Or, to employ another has been thus discovered that, like Jupiter illustration, if a watch be laid face up- and Saturn, Uranus is constructed of much ward on a table we should correctly say that its hands move from east through south to west; but, if it be held nearly upright and the face rather upwards, we should scarcely say that the hands moved from east through south to west; nor if the face were tilted a little further forward, so as to be inclined rather down-impossible that the apparent size of any wards, should we say that the hands move from east through north to west.

one of the outer planets can truly indicate the dimensions of its real globe. An atmosphere of enormous extent must needs surround, it would seem, the liquid or solid nucleus which probably exists within the orb we see.

In the case of Jupiter or Saturn, the telescope has told us much which bears on this point; and, as I have indicated in these pages, and elsewhere, there is an overwhelming mass of evidence in favour of the theory that those orbs are still instinct with their primeval fires. But in the case of Uranus, it might well be deemed hopeless to pursue such inquiries, otherwise than by considering the analogy of the two larger planets. Direct evidence tending to show that the atmosphere of Uranus is in a condition wholly differing from that of our own atmosphere, cannot possibly be obtained by means of any telescopes yet constructed by men. Some astronomers assert that they have seen faint traces of belts across the disc of Uranus; but the traces must be very faint indeed, since the best telescopes of our day fail to show any marks whatever upon the planet's face. Even if such belts can be seen, their changes of appearance cannot be studied systematically.

The great slope or tilt of the paths is undoubtedly a more singular feature than the direction of motion. Implying as it does that the planet's globe is similarly tilted, it suggests the strangest conceptions as to the seasonal changes of the planet. It seems impossible to suppose that the inhabitants of Uranus, if there are any, can depend on the sun for their supply of heat. The vast distance of Uranus from the sun, although reducing the heat-supply to much less than the three-hundredth part of that which we receive, is yet an insignificant circumstance by comparison with the axial tilt. One can understand at least the possibility that some peculiarity in the atmosphere of the planet might serve to remedy the effects of the former circumstance; precisely as our English climate is tempered by the abundant moisture with which the air is ordinarily laden. But while we can conceive that the minute and almost starlike sun of the Uranian skies may supply much more heat than its mere dimensions would lead us to expect, it is difficult indeed to understand how the absence of that sun for years from the Uranian sky can be adequately compensated. Yet in Uranian It is, however, on this very subjectlatitudes corresponding to the latitude of the condition of the planet's atmosphere London the sun remains below the hor--that the discovery I have now to deizon for about twenty-three of our years scribe throws light. in succession. Such is the Arctic* night of regions in Uranus occupying a position cosresponding to that of places in our temperate zone.

But the most important results of the discovery of the satellites has been the determination of the mass or weight of the planet, whence also the mean density of

Faint as is the light of Uranus, yet when a telescope of sufficient size is employed, the spectrum of the planet is seen as a faint rainbow-tinted streak. The peculiarities of this streak, if discernible, are the means whereby the spectroscopist is to ascertain what is the condition of the planet's atmosphere. Now, Father Secchi, studying Uranus with the fine eight-inch * It has been remarked that there is some incon- telescope of the Roman Observatory, was gruity in the name Arctic planets which I have as- able to detect certain peculiarities in its signed in my Other Worlds" to Uranus and Nep- spectrum, though it would now appear tune, when considered with reference to the theory that (owing probably to the faintness of I have enunciated that these planets still retain an enormous amount of inherent heat. Many seem to the light) he was deceived as to their eximagine that the term arctic necessarily implies act nature. He says: The yellow part cold. I have of course only used the name as indicating the distance of Uranus and Neptune from of the spectrum is wanting altogether. In the green and the blue there

the sun.

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are two

bands, very wide and very dark." But he was unable to say what is the nature of the atmosphere of the planet, or to show how these peculiarities might be accounted for.

Recently, however, the Royal Society placed in the hands of Dr. Huggins a telescope much more powerful than either the Roman telescope or the instrument with which Dr. Huggins had made his celebrated observations on sun and planets, stars and star-cloudlets. It is fifteen inches in aperture, and has a light-gathering power fully three times as great as that possessed by either of the instruments just mentioned.

in the atmosphere of Uranus. It will in-
deed be readily inferred that this must be
the case, when the fact is noted that no
signs whatever of the existence of nitrogen
can be recognized in the spectrum of
Uranus, though it is difficult to suppose
that nitrogen is really wanting in the
planet's atmosphere. Dr. Huggins also
notes that none of the lines in the spec-
trum of Uranus appear to indicate the
presence of carbonic acid. Nor are there
any lines in the spectrum of Uranus cor-
responding to those which make their ap-
pearance in the solar spectrum when the
sun is low down, and is therefore shining
through the denser atmospheric strata.
Most of these lines are due to the presence
of aqueous vapour in our atmosphere, and
it would seem to follow that if the vapour
of water exists at all in the atmosphere of
Uranus its quantity must be small com-
pared with that of the free hydrogen.

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As seen by the aid of this fine telescope the spectrum of Uranus is found to be complete, "no part being wanting, so far as the feebleness of its light permits it to be traced." But there are six dark bands, or strong lines, indicating the absorptive action of the planet's atmosphere. One of these strong lines corresponds in posi- Admitting that the line seen by Dr. tion with one of the lines of hydrogen. Huggins is really due to hydrogen Now it may seem at first view that since fact of which he himself has very little the light of Uranus is reflected solar light, doubt - we certainly have a strange diswe might expect to find in the spectrum covery to deal with. If it be remembered of Uranus the solar lines of hydrogen. But that oxygen, the main supporter of such the line in question is too strong to be re- life as we are familiar with, cannot be garded as merely representing the corre- mixed with hydrogen without the certainty sponding line in the solar spectrum; indeed, that the first spark will cause an exploDr. Huggins distinctly mentions that "the sion (in which the whole of one or other bands produced by planetary absorption of the gases will combine with a due porare broad and strong in comparison with tion of the other to produce water), it is the solar lines." We must conclude, there- difficult to resist the conclusion that oxyfore, that there exists in the atmosphere gen must be absent from the atmosphere of Uranus the gas hydrogen, sufficiently of Uranus. If hydrogen could be added familiar to us as an element which appears in such quantities to our atmosphere as to in combination with others, but which be recognizable from a distant planet by we by no means recognize as a suitable constituent (at least to any great extent) of an atmosphere which living creatures are to breathe.* And not only must hydrogen be present in the atmosphere of Uranus, but in such enormous quantities as to be one of the chief atmospheric constituents. The strength of the hydrogen line cannot otherwise be accounted for. If by the action of tremendous heat all the oceans of our globe could be changed into their constituent elements, hydrogen and oxygen, it is probable that the signs by which an inhabitant of Venus or Mercury could recognize that such a change had taken place would be very much less marked than the signs by which Dr. Huggins has discovered that hydrogen exists

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spectroscopic analysis, then no terrestrial
fires could be lighted, for a spark would
produce a catastrophe in which all living
things upon the earth, if not the solid
earth itself, would be destroyed. A single
flash of lightning would be competent to
leave the earth but a huge cinder, even if
its whole frame were not rent into a mil-
lion fragments by the explosion which
would ensue.

Under what strange conditions then
must life exist in Uranus, if there be in-
deed life upon that distant orb. Either
our life-sustaining element, oxygen, is
wanting; or, if it exists in sufficient quan-
tities (according to our notions) for the
support of life, then there can be no fire,
natural or artificial, on that giant planet.
It seems more reasonable to conclude that,
as had been suspected for other reasons,
the planet is not at present in a condition
which renders it a suitable abode for liv-
ing creatures. RICHARD A. PROCTOR.

1

From The Spectator.
MR. GLADSTONE AT GREENWICH.

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speech nevertheless. Its whole tone leaves on us the impression of a man who

MR. GLADSTONE has reconquered is entirely undaunted by the storm of obGreenwich, and under the circumstances loquy poured on him during the Recess, that is a great deal to have accomplished. who has nothing to apologize for or extenThe victory proves that the Premier has uate, who has confidence in his past peras yet lost little of his almost magical in- förmances and his future plans, and who fluence over the ordinary British elector, perceives amid all the turmoil that the over those "common masses who do not country is still upon his side. On one read the Pall Mall Gazette, but do elect subject indeed he showed weakness of an the House of Commons. The immense unexpected and very annoying kind. It crowd which assembled to hear Mr. Glad-is not for the Premier of Great Britain to stone on Saturday was at least as preju- express pleasure because von Blumenthal diced against him as any crowd in Eng- has patted the British Army on the back; land is at all likely to be. It was the only but that one slip excepted - a slip due, crowd which had personal grievances we conceive, to the fact that von Blumenagainst the Premier, which had suffered thal's approval weighed heavily with Mr. from his policy of honesty in the Dock- Gladstone as evidence about a matter on yards, which felt keenly about Naval mis- which he himself is no expert, the Prem management, which had been irritated, ier was lofty to serenity, as sure of his and not unjustly irritated, by apparent course as man may be who knows that his ulpersonal neglect. Greenwich is of all timate foothold is nothing more stable than boroughs the borough in which all causes opinion. His argument that his majority of disaffection seemed before Saturday to had already outlived previous majorities, be concentrated. It was before an assem- had in it a tinge of pride, pride such as blage more than half hostile, prejudiced Englishmen like; while his allusion to the against and not for him, that Mr. Glad- social movement, the alliance of Workmen stone appeared on Saturday; with which and of Peers, was full of a kind of playhe maintained for the first half-hour a fulness which seldom bubbles up in his mental struggle, which, as his speech speeches, except when discussing a subject went on, rose to him, warmed to him, upon which his mind is untroubled by the poured out towards him in renewed confi- mental debate which on some subjects dence and affection, till when he ended, goes on so incessantly within it. suspicion and irritation and hostility had pledge to carry the Ballot was given in disappeared, and a burst of thundering the tone of a man who saw his way, and' approval, renewed and renewed to show was himself utterly convinced, however that it was given to the man as well as to recently the conviction might have come, the orator, told the world that Mr. Glad- that secrecy was essential to the free exerstone was still the Minister and the Mem-cise of the political power involved in the ber desired by the mass of the population. right to vote. We do not believe that, The personal loftiness of the man, the nobleness of his character and purposes -always the sources of Mr. Gladstone's hold over the people had once more revealed themselves to the electors, and discontent disappeared in enthusiastic acclamation. There is not another man in England, unless it be Mr. Bright, who under such circumstances could have achieved so complete a popular triumph; and be the merit of the speech what it may, its reception at least showed that the head of Her Majesty's government is still in full rapport with the majority of her subjects, is still trusted by them, has still behind him the immense force of the popular approval. That is a great fact in the politics of the hour.

The speech itself does not appear to us, who are unaffected by the charm of the orator's voice and bearing, so great as its success, but it is a very considerable

His

but that to any man who does believe it the Ballot must seem a matter of transcendant political moment appears to us almost self-evident, as self-evident as the absurdity of declaring it less important than a Bill for protecting Miners. The power to make horseshoes properly to all future time is surely more important to the smith than the fate of any individual horse, and in this case the English people is the smith. Upon the three other great topics of the hour the Premier is equally plainspoken. He believes in his Army reforms and in his War Minister as a man who "has done much for the efficiency of the Army; states distinctly what he wants, namely, a body of officers who can handle an army scientifically as well as encourage the men to "stand like a brick wall," and who recognize that "war has become one of the most highly-developed of the arts practised by mankind;" and though he abused the alarm

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ists most unmercifully-forgetting that events, is as definite as that of any Tory geese should be reverenced if their cackle who ever lived, and it is always the same, saves Rome - he admitted that to defend -to sweep away every obstacle which England a new army, a larger and a better prevents "the English father from being had become a necessity. As to the Peers, he the father of a happy family and the cendeclared plainly that while believing that tre of a united home," which prevents the constitution of the Upper House might him, that is, from realizing his own reasonbe improved, he should think once, twice, able ideal, an ideal which the hearty cheers even thrice before he eliminated the hered- of the multitude showed that they underitary principle, for which, as he showed stood. We cannot conceive of a speech by two most amusing stories, the English uttered by a man responsible to a nation people had a sort of instinctive kindness. for every word which, within its limits, Even when protesting against the exclu- could be more definite or consistent, nor, siveness of a Cabinet they entrusted their we would add, one which, always withprotest to a Lord, and when workmen in those limits, deserves more heartily wanted social reforms they were strongly the approval and support of all good attracted by the reported adhesion of a Liberals. group of men of whom "one only was a Of course the defect of such a speech as commoner." On Education he averred, in this consists, and must consist, in its omisterms which, cautious as they are, cannot sions. To us, and as, we believe, to a vast be mistaken, that the Education Act was majority of Englishmen, the dignity and a vast stride on the road of progress, that the strength of the State, of the nation inreason and common-sense required us to corporated, its power and its disposition to utilize existing schools, and that State perform its duties abroad as well as at home, money raised by rate or otherwise "should its action and place in the world as well as not be expended on subjects on which un- at the fireside, appear elements vital to the happily religious differences prevail; " that happiness and still more vital to the nobleis, that no payment to any school should ness of character of the individual citizen. be granted or refused on account of its re- Mr. Gladstone disregards this too much, ligious instruction; that, in short, he ap- or rather allows his pity for the people, proved and intended to support Mr. Fors- for the mass whose progress upwards is so ter's Act. And finally, he told the work- choked with obstacles, to fill his mind so men that as to their special demands, they completely, that he forgets to think of the had, as a class, been relieved and raised State as well as of the units which commore than any other in the past thirty pose it; and some day or other, perhaps years had been exempted, for instance, soon, he and the nation and the Liberal from all but self-imposed taxation that party will all alike suffer for this forgetthey had received political power, and fulness. But we cannot have out of a man were about, through the Ballot, to receive what is not in him, least of all on an occafreedom for its exercise; that means had sion when, if the quality had been there, been found for their education, some- its display might have seemed incongruous times at the expense of their wealthier or inconvenient. The speech at Greenneighbours; that the road to the highest wich was a speech to constituents as ignoeducation, and therefore the highest ca- rant of foreign politics as of logarithms, reers, had through the abolition of tests and even Lord Palmerston would proband the action of the Endowed Schools' ably have avoided any reference to a topic Commission, been cleft open for them; on which, of all others, knowledge in the and that for the future the first questions audience as well as the speaker is essential for them would be the decrease of intoxi- to edification. That Mr. Gladstone was cationi.e. some moderate but effective probably grateful for the opportunity of Licensing Bill a reform in the position avoiding a subject distasteful alike to his of women as regards property and earn- intellect and his convictions is, in our ings, ie., the "removal of the social," not judgment, a misfortune, but one which the political "inequalities under which arises naturally from the special characthey labour," and the securing to labour ter of the mind that on so many other its due respect in the world, that the sides is of such inestimable service to the poor be no longer despised," but the country. When tasks so great have been idle. It is open to any man to say that performed within a space of time so small, on any or all of these subjects the Pre- when one man has, as he and we believe, mier is wrong, but it is not open to him redressed the grand wrongs of Ireland, to say that he is either feeble, or in- abolished a Church which had defied jusdistinct, or dreamy. His purpose, at all' tice for three centuries, removed the chief

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