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knowledge of these latter laws, had this word, the To all this, of course, we heartily subscribe ; key of the whole riddle, remained unpronounced. and we only wish that the limit M. de Humboldt The craving of the philosophic mind is for explana- has prescribed to himself would have permitted him tion, i. e. for the breaking up of complex phenome- to extend the scope of his remarks, clothed, as they na into familiar sequences, or equally familiar tran-are, in such animated language, to embrace a far sitional changes, or cotemporary manifestations ; / wider range of application. The frame of nature which, under the names of cause and effect, we is not bounded by that narrow limit which is comare content to receive (at least temporarily) as monly understood by the term physics. Life, ultimate facts, and which nothing but perfect thought, and moral and social relation, are all familiarity divests of that marvellous character equally natural-equally elements of the great which they really possess—which are only not scheme of the Kosmos with matter and magnetism. looked upon as miraculous because they are usual. The only imaginable reason why the sciences When we work our way up to facts of this char-growing out of these ideas are not regarded and acter, physical inquiry ends, and speculation begins. handled, or have not hitterto effectually been so, Very few such ultimate facts. have hitherto been as branches of natural science and inductive inquiry, arrived at in physics ; and it is to the increase of is the great difficulty of arriving at true statements their number, by future inquiry, that we must look of facts in some, owing to the conflict of partial for any prospect of erasing any one of them from interests, and the great danger and consequent the list, i. e. of explaining it. No doubt expla- heavy responsibility attending experiments in others. nation must ever be imperfect, if quantitative laws These obstacles can only be removed by the genbe wanting as a feature. But the first, at least eral enlightenment of mankind, enabling them to the most necessary office of experimental philos- perceive that their true interests require truth in ophy, is, the detection of the influential thing, the the statement of facts ; deliberate caution in underultimate fact, or facts, on which explanation hinges taking, and patience—long, calm, enduring pa

-its subsequent, and, in that sense, subordinate, tience—and hearty coöperation, in watching the though still most useful and important one; to dis- working out of social and legislative experiments. cover the formal and quantitative laws of that in- A great and wondrous attempt is making in fluence. If, indeed, it be said, that the proposition civilized Europe at the present time: neither more announcing these ultimate facts is a law, in the nor less than an attempt to stave off, ad infinitum, sense of the word intended, we protest against the the tremendous visitation of war; and, by removabuse of language, which confounds, under one ing or alleviating the positive checks to the growth form of expression, the detection of the law itself, of population, to diminish the stringency of the and the subject matter of the law-the quod loqui- preventive ones, and to subsist continually increasmur, with the de quo.

ing masses on a continually increasing scale of With the richness of idea and command of re- comfort. May it be successful! But the only source which natural knowledge confers, civilization conditions on which it can be so are, that nature goes hand in hand. The remarks of M. de Hum- be laid yearly more and more under contribution to boldt on this part of his subject are so pointed and human wants; and that the masses themselves impressive, that we cannot refuse ourselves the understand and go along with the exertions makpleasure of quoting them :

ing in their favor in a spirit of amicable and rational “ The clearer our insight into the connection of conformity. To no other quarter than to the phenomena, the more easily we shall emancipate progress of science can we look for the least ourselves from the error of those who do not per- glimpse of a fulfilment of the first of these conceive that, for the intellectual cultivation and for the ditions. Neither the activity of hope, nor the prosperity of nations, all branches of natural knowl- energy of despair, acting by stationary means on edge are alike important, whether the measuring and describing portion, or the examination of chem unvarying elements, can coerce them into a geo ical constituents, or the investigation of the physical metrically increasing productiveness. Science must forces by which all matter is pervaded.

wave unceasingly her magic wand, and point unAn equal appreciation of all parts of natural knowl- ceasingly her divining rod. The task now laid edge is an essential requirement of the present on her, however, is not of her own seeking. She epoch, in which the material wealth and the in- declines altogether so dread a responsibility, while creasing prosperity of nations are in great measure yet declaring her readiness to aid to the utmost based on the more enlightened employment of nat- of her powers ; claiming only the privilege, essenural products and forces. * The most super- tial to their available exertion, of free, undisturbed, ficial glance at the present condition of European states shows that those which linger in the race and dispassionate thought, and calling upon every cannot hope to escape the partial diminution, and, class to do its duty; the higher in aiding her apperhaps, the final annihilation of their resources. plications, the lower in conforming to her rules. The danger

must be averted by the earnest cultivation of natural knowledge. limits and method of exposition of the physical de

In that part of his work which treats of the Knowledge and thought are at once the delight and the prerogative of man; but they are

scription of the universe, M. de Humboldt takes also a part of the wealth of nations, and often afford considerable pains to represent the “Science of to them an abundant indemnification for the more the Kosmos” as a separate and independent departsparing bestowal of natural riches."

ment of knowledge, distinct in scope and kind from

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a mere encyclopædic aggregation of physical sci-| sun of our own system, and all those remoter

We concern ourselves little whether in suns which glitter in the firmament. this he have succeeded in making out a useful and different measure of these effects must not prevent available distinction ; admitting, as he does, that the physical philosopher, engaged in tracing a in his mode of conceiving and handling it, it is, in general picture of nature, from noticing the coneffect, the aggregrate, by simple juxtaposition, of nection and coëxtensive dominion of similar forces." two separate and very unequal portions, similar in (Kosmos, p. 146., Transl.) character so far as the less can be similar to the We therefore entirely agree with our author in more complex. He regards it, in short, as phys- the propriety of that arrangement of his work ical geography enlarged by such a description of the which gives the precedence of treatment to the heavens and their contents as shall correspond in celestial over the “ telluric" view of nature; and plan and in conception (so far as our knowledge prefaces the description of our own globe by that extends) to that description of the earth and its of the sidereal and planetary system. And whether denizens which is intended by the former designa- such description be properly regarded as the extion. In so far, then, as physical geography is position of a body of science, or (as we should entitled to be termed a separate and independent rather feel disposed to look upon it) a sort of epos, science, kosmography, or the science of the Kos- a noble oratorio, or a grand spectacle, we are demo3, is so also, and a more general one, including lighted to receive it at his hands, and to throw our the other. A Chinese map of the globe is a map selves into that frame of mind for its reception of.the globe, and not a mere map of China, though which shall be best calculated to heighten the imthe Flowery Land figure therein in rich detail of pression, and do justice to the exponent. city, stream, and province; and though Europe, Taking our stand, therefore, on the extreme Asia, Africa, and America exist, for the most part, verge of the visible creation, let us for an instant in mere outline, and occupying an extent of surface look about us, ere we descend with him, like the altogether disproportioned to their true extent and angelic messenger in Milton, through stars, nebulæ, importance. This is not the fault of the Celestial and systems, to this planetary sphere and its central Arrowsinith. Had he known more of the globe, sun. Where are we? Is there such an extreme he would have given his countrymen a better map. verge? This question, which lies at the very

Our simile, however, is faulty in one respect. threshold of an exposition of the Kosmos, per deWhat we know of the contents of space exterior scensum, is one which has so little to recommend to our globe we at least know truly—at all events, it as a matter of discussion that we certainly should we can separate our knowledge from our ignorance ; not mention it here, had it not got involved in an and it happens, fortunately, that what escapes astronomical speculation of a very singular nature. our view is precisely that which, if seen, would The assumption that the extent of the starry firmerely serve to puzzle and perplex us; while the mament is literally infinite has been made, by one of great and obvious features which strike us are pre- the greatest of astronomers, the late Dr. Olbers, cisely those which we are best able to reduce to gen- the basis of a conclusion that the celestial spaces eral laws, and to view in systematic connection, are in some slight degree deficient in transparency ; and which reveal to us, in its grandest form, the so that all beyond a certain distance is, and must Unity of the Kosmos. The all-pervading power forever remain, unseen; the geometrical progresof gravitation, that mysterious reality by which sion of the extinction of light far outrunning the every material being in the universe is placed in effect of any conceivable increase in the power of instant and influential relation with every other, our telescopes. Were it not so, it is argued, springs forward in a state of disengagement and every part of the celestial concave ought to shine prominence on the contemplation of the celestial with the brightness of the solar disc; since no movements which it, perhaps, might never have visual ray could be so directed as not, in some assumed had not the opportunity been afforded us point or other of its infinite length, to encounter of so contemplating it, apart from the distracting such a disc. With this peculiar form of the arguinfluence of corpuscular forces which, in innumer- ment we have little concern. It appears to us, able instances, inask and overlie it in its exhibition indeed, with all deference to so high an authority, on the surface of our planet. And again : the invalid ; since nothing is easier than to imagine phenomenon of light, its uniform properties and modes of systematic arrangement of the stars in equal velocity from whatever quarter of space it space (entirely in consonance with what we see reaches us, and the certainty those properties afford around us of the principle of subordinate grouping of the existence of a perfectly uniform mechanism, actually followed out) which shall strike away the coëxtensive with space itself, continually occupied only foundation on which it can be made to rest, in the discharge of the most important of all offices, while yet fully vindicating the absolute infinity of that of conveying at once information and vital their number. It is the conclusion only which it stimulus from every region of space to every other appears to us important to notice, as having re-facts of this kind, were there no other, would cently been attempted to be established on grounds suffice to force upon our minds the clear percep- of direct statistical enumeration of stars of different tion of a unity of plan and of action in the consti- orders of brightness, by the illustrious astronomer tution of nature. “A connection is maintained, of Pulkova, in a remarkable work, (Etudes d'Asby means of light and radiaht heat, both with the tronomie Stellaire,) and even some rude approx

imation made to the rate of extinction. It would accumulating in the opposite direction, and that lead us far beyond our limits to attempt even to such“ nebulous stars” may, after all, be only exgive a general idea of his reasonings, but one re- treme cases of central condensation, such as two or mark on the whole subject we cannot forbear. three " nebulæ,” usually so called, offer a near apLight, it is true, is easily disposed of. Once ab- proach to. A part, then, from these singular bodies, sorbed, it is extinct forever, and will trouble us no and leaving open the questions they go to raise, and more. But with radiant heat the case is otherwise. apart from the consideration of such peculiar cases This, though absorbed, remains still effective in as planetary and annular nebulæ, the great majority heating the absorbing medium, which must either of nebulæ may be described as globular or spheincrease in temperature, the process continuing, ad roidal aggregates of stars arranged about a centre, infinitum, or, in its turn becoming radiant, give the interior strata more closely than the exterior, out from every point at every instant as much heat according to very various laws of progressive denas it receives.

sity, but the strata of equal density being more Of the supposed luminiferous ether itself, as nearly spherical according to their proximity to the one of the material or quasi-material contents of centre. Many of these groups contain hundreds, space, M. de Humboldt says nothing. He waives, nay, thousands, of stars. designedly, at least in the present volume, any al- Besides these, there exist nebulæ of a totally lusion to that, and all other theoretical conceptions. different description ; of vastly greater apparent The view of creation which he takes, and which dimension, and of very irregular and capricious we must take with him, is so purely and entirely forms, of which the well-known nebula in Orion objective, so closely confined to what Mr. Mill is an example. They form, evidently, a class would call the collocations of the Kosmos, that apart from the others, not only in aspect, but also even the Newtonian law of gravitation, with its as regards their situation in the heavens ; for noble train of mathematical consequences, is ex- whereas the former congregate together chiefly in cluded from all direct and special notice. We a great nebulous district remote from the Milky must not, therefore, wonder, but accept it as part Way, or are otherwise scattered over the whole of the determinate plan of the work, that light heavens, (though by no means so as to form what itself is spoken of only incidentally, as affording M. de Humboldt terms a “nebulous milky way," a measure of sidereal distance by its velocity, and or zone of nebulæ surrounding the sphere,) these as conveying to our eyes the images of remote only occur in the immediate vicinity of the galaxy, sidereal objects, not as they now exist, but as they and may fairly be considered, if not as integrant existed years or ages ago; or that no account is portions, at least as outliers of it. Their forms, given of the Gaussian generalizations of the the- therefore, may be considered as in some degree ory of the terrestrial magnetism~a subject, of indicative of the true form of that starry stratum, which M. de Humboldt is so preëminently cogni- could we contemplate it from a distance, so far, at zant, that it must have required the greatest self- least, that we may reasonably suppose it quite as control, and the most entire satisfaction with his irregular and complex as we observe these, its appre-conceived views of the limits of his subject, pendages, actually to be. to have avoided dilating on it.

M. de Humboldt leans, as might be expected The most remote bodies which the telescopes from one especially conversant with organic forms, disclose to us are, probably, the nebulæ. These, to that view which represents the nebulæ as sideas their name imports, are dim and misty-looking real systems, in process of gradual formation by objects, very few of which are visible to the un- the mutual attraction of their parts, and by the assisted sight. Powerful telescopes resolve most absorption of the strictly nebulous element into of them into stars, and more in proportion to the stellar bodies. “ The process of condensation," force of the instrument; while, at the same time, he says, “ which was part of the doctrine of Anevery increase of telescopic power brings fresh and aximenes, and of the whole Ionic school, appears unresolved nebulæ into view. A natural general- to be here going on before our eyes.

The subject ization would lead us to conclude that all such of conjoint investigation and conjecture has a pecuobjects are nothing but groups of stars, forming liar charm for the imagination. Throughout the systems, differing in size, remoteness, and mode range of animated existence, and of moving forces of aggregation. This conclusion would, indeed, in the physical universe, there is an especial fasbe almost irresistible but for a few rare examples, cination in the recognition of that which is becomwhere a single star of considerable brightness ap- ing, or about to be, even greater than in that which pears surrounded with a delicate and extensive is, though the former be indeed no more than a new atmosphere, offering no indication of its consisting condition of matter already existing ; for of the of stars. Such objects have given rise to the act of creation itself, the original calling forth of conception of a self-luminous nebulous matter, of existence out of non-existence, we have no expee vaporous or gaseous nature, of which these rience, nor can we form any conception of it.” photospheres, and, perhaps, some entire nebulæ, That the whole firmament of stars visible to us, may consist, and to the further conception of a even with the help of telescopes, belongs to that gradual subsidence or condensation of such matter vast sidereal stratum which we call the Galaxy, into stars and systems. It cannot be denied, how- seems hardly to admit of doubt. The actual ever, that the weight of induction appears to be form of this stratum; further than that it is not improperly characterized as such, can hardly be tion by Herschel, has now been distinctly traced said to be known with any approach to certainty ; in fifty or sixty instances, (M. de Humboldt, anticbut that its extent in a direct line outwards is enor-ipating what will doubtless one day prove to be a mously greater in some directions than in others, fact, says 2800,) among which occur examples of and that in one portion of its extent it is, as it were, periodic revolutions of 200, 182, 117, 61, 44, and eleft, and contorted, in others lengthened into pro- even 17 years, and of orbits, in some cases so eccesses stretching far into space, seems to rank among centric as to be quite cometary, in others nearly the positive conclusions of astronomy. In certain circular. Some again are concluded, with much directions its extent would seem to be unfathoma- probability, to revolve on their axes, from the obble to our best telescopes ; in others, there is rea- servation of regular periodic changes in their lusson to believe we see through and beyond it, even tre; while others vary in no regular and certain in its own plane.

periods, undergoing great and abrupt changes, for Of the distance of the stars of which this vast which no probable cause has yet been assigned. stratum consists, at least of some of the nearest of In one remarkable instance a change of color them, we are beginning, at length, to possess some would appear to have taken place. Sirius, which certain knowedge. The bright star a Centauri has is now one of the whitest of the stars, is characa measured parallax (as the observations of Hender- terized by Ptolemy as red, or at least ruddy. 0 son and Maclear teach us) of nearly a whole second, dè Erigios, vróxiggos, is his expression, speaking (0°-9128,) which places it at a distance from us pointedly of its color, and not of its scintillations. equal to 226,000 radii of the earth's orbit. That Not the least surprising, is the actual and posiof 61 Cygni has been ascertained by Bessel to be tive knowledge we have obtained of the weight or no less than 592,200 such radii, while the observa- quantity of matter contained in at least one of the tions of Struve place a Lyræ at 789,600 of simi- binary stars, 61 Cygni ; from whose orbital molar units from our system. Such is the scale of tion, compared with its distance, Bessel has conthe system to which we belong, such the magni- cluded that the conjoint mass of its two individuals tudes we are led to regard as small, in comparison is “neither much more nor much less than half with its actual extent ! The number of stars the mass of our sun." It appears as a star of the whose distance is imperfectly known to us at sixth magnitude. From the photometric experipresent is about thirty-five, seven of which may ments of Wollaston on a Lyræ, compared with be considered as determined, with some approach what we know of its distance, its actual emission to certainty, by the recent researches of Mr. of light may be gathered to be not less than 54 Peters.

times that of the sun. Sirius, which is nine times Among the countless swarm of what are com- as bright as a Lyræ, and whose parallax is insenmonly called fixed stars, there is not one, proba-sible, cannot, therefore, be estimated at less than bly, which really merits the name. In by far the 100 suns. great majority, a minute, but regularly progressive, Non-luminous stars have been conjectured to change of place is observed to take place; and, exist, and Bessel even considered that some irregfrom a careful examination of these movements, ularities, supposed to subsist in the proper motions as observed in stars visible in Europe, it has been of Procyon and Sirius, could no other way be acconcluded that a portion at least of them is only counted for than by supposing them to be revolvapparent, and arises from a real motion of our ing about invisible central bodies. The illustrious own sun, carrying with it the whole planetary astronomer of Pulkova, in the work we have already system, towards a point in the constellation Her had occasion to cite, has, however, by destroying cules, in R. A. 259° 35' decl. 34° 34' north. This the evidence of irregularity by a careful revision extraordinary conclusion, resting as it does on the of all the recorded observations, rendered it unneindependent and remarkably agreeing calculations cessary to resort to such an hypothesis. of five different and eminent astronomers, from Neither have attempts been wanting to deduce data afforded by northern stars, has, within the from the proper motions of the stars the situation last few months, received a striking confirmation in space of the “Central Sun,” about which the by the researches of Mr. Galloway, who has ar- whole firmament revolves. Lambert placed it in rived at the very same conclusion, from calcula- the nebula of Orion ; Maedler, Very recently, in tions founded on the proper motions of stars in the Pleiades, on grounds which, however, appear the southern hemisphere, not included among those to us anything but conclusive. used by his predecessors. In this path the sun The vast interval which separates our system moves with the prodigious velocity of 400,000 miles, from its nearest neighbors among the fixed stars, or nearly its own semi-diameter, per diem. is a blank which even the imaginations of astrono

Independent of the movements of translation mers have been unable to people with denizens of not accounted for by this cause, several of the any definite character, other than a few lost comets stars have a rotary motion, forming pairs or binary slowly groping out their benighted way to other systems, called double stars, revolving about each systems, or torpidly lingering in aphelio, expecting other in regular elliptic orbits, governed by the their recall to the source of light and warmth. In Newtonian law of gravitation. This sort of con- the utter insulation of this huge interveuing golph, nection, suggested as theoretically probable by it is impossible not to perceive a guarantee against Mitchell, and demonstrated as a matter of observa-l extraneous perturbation and foreign interference, or to avoid tracing an extension of the very same us of the exceedingly firm grasp by which theory principle of subordinate grouping which secures has seized on this most complicated subject; by the satellites of our planets from too violent a per- the fact of the discovery having been made almost turbative action on the part of the central body. simultaneously by two geometers of different naIt thus assumes the character and importance of a tions, pursuing different courses of investigation, cosmical law; and, while it affords another and each in entire ignorance of the other's proceedmost striking indication of the unity of plan which ings, and arriving at what may fairly be termed pervades the universe, may lead us to believe that, the same identical place of the yet unseen planet. if other systems yet exist in the immensity of space, It is not a little remarkable that astronomy, the they may be separated from our own by intervals oldest, and, as it might be considered, the maso immense as to appear only as dim and nebu- turest among the sciences, is perhaps at this molous specks, or utterly and forever to elude our ment the most rapidly progressive of any, such is sight.

the novelty as well as the magnitude of the facts Descending, now, with our guide through this which every year brings forth. vacuum inane to our own system, we shall for a M. de Humboldt in this division of his subject, moment depart from his arrangement to strike at presents us with a rapid, but an extremely strikonce upon its central body-our own sun. This, ing and well-digested view of the “collocations" indeed, can hardly be called a departure, since, by of our system; that is to say, of the actual aran extraordinary omission, we find no special notice rangement and distribution of its masses in respect taken by M. de Humboldt of this magnificent globe. of their magnitudes, densities, and distances from Yet, surely, there is matter of sufficient interest in the sun, their times of rotation on their axes, and what is known and seen of its physical constitution the extent of their provision with satellites. We and important peculiarities, to have justified, in- have never met with a better exposé of these pardeed to have required, their not being passed sub ticulars, grouped as they are under a variety of silentio in a physical description of the universe. If aspects, with the object of bringing into view the there be much, as yet mysterious, in its inexhaust- general relations, if any, which exist between ible emission of light and heat, there is also much them. in the mechanism by which that emission is pro

“It has been proposed to consider the telescopic duced which is matter of ocular inspection. We planets,” now eight in number, between Mars and know, for instance, that the sun is not simply an Jupiter, “with their more eccentric, intersecting, incandescent mass; that the luminous process, and greatly-inclined orbits, as forming a middle whatever its nature, is superficial only, being zone, or group, in our planetary systein; and if we confined to two strata of phosphorescent clouds, follow out this view, we shall find that the compar

ison of the inner group of planets, comprising Merfloating in an atmosphere of considerable but imperfect transparency, extending to a vast distance cury, Venus, the Earth, and Mars, with the outer

group, consisting of Jupiter, Saturn, Uranus," (and beyond them; that these clouds are often driven Neptune,) “presents several striking contrasts. asunder by tumultuary movements of astonishing The planets of the inner group, which are nearer energy and extent, disclosing to our eyes the dark the sun, are of more moderate size, are denser, surface below; that the region in which these rotate round their respective axes more slowly, in movements take place is confined to an equatorial nearly equal periods, differing little from twentybelt of about sixty degrees in breadth, being, how- with one exception, without satellites. The exter

four hours, are less compressed at the poles, and, ever, comparatively much less frequent in the im- nal planets *** are of much greater magnitude, mediate vicinity of the equator itself. We know, five times less dense, more than twice as rapid in moreover, that the time of its rotation (25$ days) their rotation round their axes, more compressed at stands in decided and pointed dissonance with the the poles, and richer in moons in the proportion of Keplerian law of the planetary revolutions, and that seventeen" (eighteen) “to one.” therefore the sun has most certainly not been So soon as we descend to particulars, however, formed by the simple subsidence of regularly rotat- we find these general relations broken in upon by ing planetary matter gradually contracting in dimen- continual exceptions. The history of the discovery sion by cooling ; a fact which the advocates of the of Neptune has afforded a signal instance how little nebulous hypothesis must, therefore, render some reliance could be placed on a law of collocation, other account of.

which had begun to be considered as a fundamenThe primary planets known to us at the present tal relation pervading the whole system. Still, as moment are sixteen in number, including no less such laws, partially carried out, they possess a than five which have been added to the list since peculiar interest, especially when we consider the the publication of the Kosmos in 1845. The dis- exactness of numerical relation which holds good covery of one of these, Neptune, by the mere con- in several instances, and which leads irresistibly to sideration of the recorded perturbations of the speculate upon causes, as is the case with all close remotest planet previously known, by the theory numerical coinciden which nothing can perof gravitation, as delivered by Newton, and ma- suade us to believe purely accidental when they tured by the French geometers, will ever be re- take place in matters of fact. Why, we are garded as the most glorious intellectual triumph tempted to ask, do the diurnal rotations of Mer of the present age. If anything could enhance its cury, the Earth, and Mars, agree to a minute ! claim to be so considered, it is the assurance given | Why are the densities of the Sun, Jupiter, Ura

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