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yield a bitter-sweet extractive (picroglycion), 21; vegeto- ! System in a rough manner. This, we think, it may be useful animal matter, 3; gummy extractive, 12; gluten with wax, to do in such a manner that any two plarets may be com1; resin with benzoic acid, 2 ; gum, starch, salts (chiefly of pared with one another without computation. lime), 6; and woody fibre, 62. Solanina has been found And first, as to the relative distances from the sun, we by Dessosses. Whether picroglycion is a distinct principle, have the following table :or a combination of solanina with sugar, is doubtful.

100) 54 391

15

41 20 Bitter-sweet, when taken fresh, has a slightly narcotic in

우 187 100 72 47 27 139 76 38 fluence, causing also nausea, vertigo, and a dryness of

258 138 100 66 38 192 105 52 throat, like other solanaceous poisons. If delirium display

394 211 152 100 58 293 160) 79 itself, it is always of a most frantic kind. Perspiration or an increased discharge of urine generally occurs, followed

612 327 237 155 90 455 2481 123 by gentle purging.

690) 369 267 175 101 513 280 139 Bitter-sweet is chiefly employed in cutaneous diseases,

71.51 382 277 182 105 532 290 144 especially of the scaly kind, such as lepra; it may be given

1 716) 383 2771 182 105 533) 291 145 iniernally, while a strong wash of it is applied externally. It is also useful in some vesicular diseases, such as herpes

14 1344 719 520 341 197|1000 545 271 and eczema. In these its virtues as an external application

h 2464 1319 954 626 361||1833 1000| 497 may be increased by dissolving in it sulphuret of potass. H 4955/265219181259|| 72513686/2010/1000 This combination relieves most effectually the intolerable

This table is a succession of columns, each of which l'eirritation of these complaints. It is usually ordered in the form of decoction, but long the sun. In each column one of the distances is made 100

presents the comparative mean distances of the planets from boiling is desiructive of its powers. Siow simmering is preferable. The extract, when prepared from the fresh plant in the fifth column, in which the mean distance of the four

or 1000, and the rest are expressed accordingly; except only with a low degree of heat, is a good form for internal admi- small planets is made 100. Thus we see by inspection that nistration, as it may be combined with antimonials. In cases of poisoning by the berries, the stomach pump 19 times as far as the Earth ; about 267 times as far as Venus;

Uranus is about 124 times as far from the Sun as Mars; about should be used as speedily as possible, and moderate vene

and about 74 times the mean distance of the four small section is of service. SOLAR CYCLE, [PERIODS OF REVOLUTION.]

planets. Also, taking the mean distance of the small SOLAR SYSTEM. We have given the elements of the planets, we see that the distances from the sun are as the planetary motions minutely in the several articles MER the first away from all the rest we have 12, 23, 43, 85, 182,

numbers 15, 27, 38, 58, 100, 197, 361, 725; and if we take CURY, Venus, &c., together with such physical peculiarities as belong to them severally, and independenily of the 346, 710, in which it will be observed that each is about System; ihe general phenomena of their motions have been sion, without assigning a law; and

had also noticed that

double of the preceding. Kepler had observed a progresdeduced from the great principle of GRAVITATION; their history, as far as it is in the plan of this work to give it, has which has just been noticed; noticing also the apparenily

one terın appeared to be missing. Bode assigned the law been treated in AstroNOMY.' It remains to bring together missing term. The existence of a planet between Mars and the dimensions of the various parts of the system, and to Jupiter was accordingly suspected; and at last, to the notice such points as could not properly find a place under astonishment of astronomers, four little bodies, looking any of the heads just mentioned. By the Solar System is meant that collection of bodies covered at a distance from the Sun so near to that which

more like fragments of a planet than, planets, were diswhich contains the sun, the planets which revolve round had been suspected, that their mean distance fills up its him, their satellites, and such periodic comets as have had place in the series as well as that of any other planet. It their returns successfully predicted. The system of the antients includes the Earth as a fixed centre, with the Moon, been discovered) that these were remains of some planet

was of course immediately suspected (when only two had Mercury, Venus, the Sun, Mars, Jupiter, and Saturn. That which had been shaitered by explosion or other cause ; and of the moderns includes at this day ihe Sun as a governing the encouragement which this idea gave to look for further body (but not as a fixed centre), Mercury, Venus, the Earth (with the Moon), Mars, Vesta, Juno, Ceres, Pallas, fragments, was perhaps one of the inain causes of the dis

covery of the remaining two. This law of Bode, as it has Jupiter and four satellites, Saturn (with the ring) and seven

been called from the astronomer who first noticed it, may be satellites, and Uranus with six satellites, besides the comets

ihus expressed: if a be the distance of Mercury, and a + b of Halley, Encke, and Biela. The following symbols are

of Venus, then a + 2b is that of the Earth, a + 46 of Mars, used to represent these bodies, to which we add the received

a + 8b of the small planets, a + 16b of Jupiter, a + 32b of explanation, without expressing any opinion about it:

Saiurn, and a + 646 of Uranus; all nearly. O Sun o Mars 24 Jupiter

To convert the above relative distances into actual ones, X Mercury 6 Vesta (nodern) 5 Saturn

consider the distance from the sun to the earth as 23984 Venus

I Juno (modern) Uranus (modern) mean semidiameters of the earth, the mean semirliameter e or Earth (mo- ? Ceres (modern)

being 3956 miles; so that the distance in question is 95 > Moon [dern) | Pallas (modern)

millions of miles. The semidiameter of the sun is 111.454 left of a face surrounded by.rays: Mercury has the cadu- One of our objects in this article is to correct the absurd The symbol for the Sun is all that modern abridgment has times that of the earth ; so that the distance of the earth

from the sun may be called 215 semidiameters of the sun. ceus, or rød, entwined by two serpents : Venus a circular notions derived from the playthings called orreries, and looking-glass with a handle: the Earth (a modern symbol) has a sphere with an equator, and also (with some) an in the diagrams exhibited in books and lectures. Let the verted symbol of Venus. Those who first used it did not, of the article in this work represent the sun; then the

capital letter 0 of the type which stands at the beginning we presume, know that they might be making a looking glass earth is a speck which would need a good microscope to turned upside down represent their planet. The symbol of show it; and its distance-from the sun is represented by the moon is obvious : Mars bas what remains of a spear 11 inches, or nearly two inches more than the lengih of one and shield: Vesta, an altar with fire on it: Juno, a sceptre: of our columns. Sir John Herschel describes the Solar Ceres, a reaper's scythe: Pallas, the head of a lance: Ju

System thus:piter, supposed to be a symbol of the thunder (arm and hand holding thunder?): Saturn, an altered form of a mower's

Object which represents it.

Representative oils scythe, the emblem of time: Uranus, the initial letter of Sun. Globe of 4 feet diameter. Herschel, the discoverer's name, with a symbol of a planet Mercury. | Grain of mustard seed. 164 feet. attached. But others have thought that Mercury was de- | Venus.

284 feet. signated by putting o and r together, the initials of orixßwv; | Earih.

430 feet. Venus, from the first and last letters of owocópos; Jupiter, Mars. A rather large pin's head. 654 feet. from the first and last letters of Zeus. These signs are Juno, &c. Grains of sand.

1000 to 1200 feet found on very old manuscripts and gems, variously figured, Jupiter

A moderate sized orange. Half a mile. but all with some general resemblance to the modern Saturn.

A small orange.

s of a mile. printed forms.

Uranus. A full sized cherry, or small A mile and a half, We are now to state the relative dimensions of the Solar

plum.

Planet.

distance from the sun.

A pea.
A pea.

2

The excentricity of a planet means the fractional part of elements are noted in the articles devoted to the diferent a planet's mean distance by which its greatest or least dis- planets. tance exceeds or falls short of the mean distance. Ar ranging the planets in the order of their excentricities, we have For Venus .007 | For Saturn (56 | For Mercury -206 Earth .017 Ceres

'078

Pallas

.242 Uranus .047 Vesta *089 Juno “258

Jupiter .048 Mars *093 That is, if the mean distance of Venus were called 1000, its greatest distance would be only 1007 and its least 993. But if the mean distance of Juno were called 1000, its greatest distance would be 1258 and its least distance 742.

We now give a table for the times of revolution, similar to that given for the distances :100 39 24 13

20 81 3 2 255 100 62 331

14 52 21 7 415 163 100 53 23 84 35 12 781 306 188 100 44 159 65 22

- Venus
Pallas

Cares

Juno
-Pallas

Urense

Jupiter

A

6

Mars

[ocr errors]

-Vesta

sun:

Rev.

Rev.

88 225 365

[ocr errors]

Conj. Ang
116
584 4445

274
146

1326 503
1593 474

62.8
59.5
59.3

Conj. Ang.
43331 399 23:1
h 10759
30687

3.26

1507 590

363 193 84 306 126 43 1810 709 436 232 101 3681 151 52 7 1911 748 460) 245 107 3881 160 55 1 1917 751 462 246| 107 3891 160 55 Jupiter and his satellites might be enclosed in a sphere

having a radius of about 2} times as great as that of the 4925 1929 1186 631 276||1000 412 141 sun; Saturn and his satellites in a sphere of 7 the radius h 11950 4680 28781531 6692428 1000 343 of the sun; and Uranus and his satellites in a sphere of 4 y (34880 113660 18401 4467||1952||7082/29181000 the radius of the sun. The earth and moon (Moon) might

be contained in a sphere of one-half the radius of the sun. The explanation of this table resembles that of the preceding one, times, instead of distances, being the objects of Venus from 10" to 61"; Mars from 4" to 18"; the small

In apparent diameter Mercury' varies from 5' to 12"; comparison. Thus, if a revolution of Jupiter contain 1000 planets have diameters hardly measurable; Jupiter from parts of time, that of Saturn has 2428 such parts: and the 30" to 46"; Saturn from 14" to 18"; Uranus from a little revolution of Uranus is 84:01 as long as that of the earth.

less to a little greater than 4". In the following table will be seen the absolute time of

If the radius of the sun were divided into 1000 parts, revolution in days, and also numbers expressive of the com

there would be as follows in the radii of the several planets: parative angles moved over in a day by each planet, and — Mercury, 3}; Venus, 8; the Earth, 9; Mars, 4); Jupithe intervals (in days) between two conjunctions with the ter, 974; Saturn, 85; and Uranus, 39. If the bulk of the

sun were divided into a million of parts, Mercury would be Int. of Comp. Rev. lot. of Comp.

Int. of Comp. a little less than one-twentieth of one of the parts; Venus, Conj. Ang 1137 75.4

two-thirds of a part; the Earth, three-quarters of a part;

378 9:29 Mars, one-tenth of a part: Jupiter, 925 parts; Saturu, 720 1691 467

370 687

parts; Uranus, 58 parts. The Moon is about the third part 780 (16871 466

of Mercury in bulk. Thus, Venus revolves in 225 days (all the numbers in

The mass of the planets varies very much from what it this article are more roughly given than in the articles would be if they were nearly of the same substance. From specially devoted to the planets); is in conjunction with the the effects of the planets in attracting their satellites, comsun at intervals of 584 days; and, with its mean mo- pared with the effects of the sun upon themselves, it is tion, would describe 274° in the heavens while Jupiter de- found that if

, according to Cavendish's experiment, we scribes 230.1. Saturn moves 2:01 minutes daily; the earth, take the earth to be, at a mean, 5} times the density of 59' 8''•3.

water, or about half that of lead, the sun may be considered, The minor elements (in a general consideration) may be as to density, to be made of asphaltum, or rather heavy best described by diagrams; the inclinations of the orbits coal; Jupiter of the same; Uranus of a material very little may be represented by the following lines, which show the heavier ; Saturn of maple-wood; the Moon of diamond or slope or inclination of each orbit to the orbit of the earth or topaz. By other modes, of course, than that of their satellites, plane of the ecliptic. None of the old planets have an inclina- Mercury is found to be three times as dense as the Earth; tion of more than 7°, while in the new planets the same Venus of about the same density; and Mars about threeelement varies from 70 to 35o.

quarters as dense as the Earth.

The sun revolves about its axis in about 251 sidereal days; Mercury, Venus, the Earth, and Mars, all revolve in about the same time, from 23} h. to 24 h.; Jupiter and Saturn severally revolve in about 10 h. and 101 h. About Uranus nothing is known in this respect.

From what precedes, a sufficient general notion may be collected of the dimensions of the Solar System, and we now proceed to some other points connected with it. As to its lace among the fixed stars, it is only within the last two years that the distance of any star from our system may be said to have been positively measured. [Parallax.] The star 61 Cygni is shown to be more than 340,000 times as far from our system as its most distant discovered planet is from the sun. As to the question of the motion of the Solar Sys

tem in space, no such phenomenon has been made apparent. In the next figure the plane of the ecliptic is represented : Were any such motion to exist, of a degree sufficient to OB is the line which points to the astronomical first point of have a sensible effect, it is obvious that the stars which the Aries, or the vernal equinox, and the arrows represent the system is leaving would appear to draw nearer together, directions of the planeiary motions. On the outer circle are while those to which it is approaching would appear to bea represented the longitudes of the ascending nodes of the come wider apart. W. H.erschel thought at one time that different planets, or the lines in which they are found when some such phenomenon was slightly perceptible, and that they rise through the ecliptic from the southern to the the system was in mos.ion towards the constellation Hernorthern side of it. On the inner circle are represented the cules; but the fact bas received no confirmation. That the longitudes of their perihelia, or points of nearest approach whole System is in moʻtion more or less, mechanical consito the sun. The slow changes which take place in these I derations make almost certain. Whatever motion the cene

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tre of gravity had at any one time, it is demonstrable that it described in either assertion. Our object is to clear the must keep unaltered, except by the attraction of the fixed nebular hypothesis from the unphilosophical character with stars; and it is millions to one against there having been which its first appearance is thus presented, and by no no motion whatever of this centre at the time when the sys. means to uphold the moral dignity of Laplace. Until the tem received its organization. And if there be any attrac-biting facts connected with his treatment of his benefactor tion from the fixed stars, however little, some motion must (Vol. xiii., p. 325] are answered or explained, that great be produced. Centuries of close observation on double stars mathematician must be called a time-server; and we susmay, and probably will, detect the motion of our system. pect that his ‘Système du Monde' only treats the intelligent All that can be said up to the present time is, that, be it | Creator whom his mind acknowledged, in the same manner what it may, it is exceedingly small, compared with the dis- as he afterwards treated Napoleon. It was published in 1796, tance of our System from these stars.

a period which would well explain the mere suppression of all The next question may be, is there any evidence in our allusion to the Supreme Being: and one of these things must System of any secondary law of formation, indicating a con- be true; either Laplace was what Mr. Whewell styles him, nection between the mode of creation of one planet and or he had not the courage to declare himself otherwise in another. The will and power of the Creator are the final his age and country. But what we have here to do with causes both of the initiation and maintenance of this vast is the assertion that he did more-that he attacked the machine; but in the latter there are visible secondary laws, doctrine of a Supreme Being. His words are as follows, the that of attraction, for instance: were there any in the former? passages to which we wish to draw attention being in Attempts at investigation on this point have been frequently Italics :- I cannot here help observing how much Newton considered atheistical; a foolish notion arising out of those has departed on this point from the method wbich he elseviews to which we have alluded in Motion, p. 452. Those where so happily applied. After the publication of his who can only think of the Creator and forget the Maintainer, discoveries, this great geometer, abandoning himself to and who virtually separate the office of the latter, and give it speculations of another nature, inquired into the motives to the laws of nature,'may reasonably fear that they would which made the Author of nature give to the Solur System have to give up also the former oflice to the laws of crea- the constitution which we have described.' Laplace then tion,' if such were found; which would be (but owing only quotes Newton's Scholium (PRINCIPIA, pp. 10, 11, where to their own interpretation of the manner in which the world we have translated the whole) thus : 'And all these regular continues to exist) a renunciation of the idea of Deity in the motions have no origin in mechanical causes,'* &c. &c. contemplation of the manner in which it began to exist. down to all parts of ihe heavens. He then further quotes, But to those who keep constantly in view the fact which no : This most elegant group, &c. can only arise from the modern theist disputes, that the same power which created design and government of a powerful and intelligent Being.' continues to create in preserving, and that the laws of na He (Laplace) continues thus, speaking, so far as the mere ture' are only expressions of the manner in which this pre- notion of a Supreme Being is concerned, rather in approbaservation is seen to act, will look upon the laws of tion: 'He repeats the same thought at the end of his creation' to be as simple and natural an object of phi- Optics, in which he would have been still more confirmed if losophical inquiry as those of the ascent of sap in a plant, he had known what I have demonstrated, namely, that the or of the revolution of a planet. The proper reply to a arrangement of the planets and satellites is precisely that charge of atheism brought against those who investigate which makes a certain provision for their stability. “Blind any mode of action of the Creator of the universe, at any past destiny,” says Newton, ** can never make the planets move time, is the retort of semi-atheism against those who make it. thus with such small irregularities, which appear to come

Many speculations have been made upon the formation from the mutual action of the planets and comets, and which of the several planets, but none which has any appearance will probably become greater and greater in the course of of connecting ihe phenomena of one planet with those of time, until at last the System will again require its author another, except by Laplace (Système du Monde, vol. ii., to put it in order." But,' proceeds Laplace, ‘may not this note 7), in what has been calier the nebular hypothesis. arrangement of the planets be itself a consequence of the This conjectural theory, which is well worthy of aitention, laws of motion, and may not the Supreme Intelligence, never received any particular notice, to our knowledge, from which Newton makes to interfere, have already made it any writer in this country, until Mr. Whewell's 'Astronomy depend upon a more general law? Are we to affirm that the and General Physics,' the third of the Bridgewater Treatises, (unlimited) preservation of the Solar System is a part of the appeared, in which it is announced that the nebular theory intentions of the Author of nature ! This we should suin was ushered in with expressions which showed Laplace to up as follows: Laplace charges Newton with a departure be a professor of atheism. What Laplace really thought from philosophical principles in-1, Speculating on the on these subjects, as we have said before (LAPLACE), we do motives of the Creator ;** 2, Assuming the probability that not know, nor would it really matter if he were what he was his works would not last his time without his own superrepresented to have been; for a conjecture may be ingenious, natural interference; 3, Assuming that he intended to and a thoory sound in its details, even though its author preserve the Solar System for ever. But Mr. Whewell made it stand in the place of a Creator. But considering the singles out only one part of Laplace's quotation, and without collateral associations connected with such a charge, it will paying any aitention to the remarks which explain his be well to examine into the fact whether there was any meaning, declares that Laplace ‘ pointed at Newton's desuch announcement; and to do this fairly, we must quote claration of belief in God as a piece of bad philosophy; both Mr. Whewell and Laplace. The former says,—We whereas this part of his quoiation is only followed by the have referred to Laplace as a profound mathematician, who remark how much stronger be himself (Laplace) had been bas strongly expressed the opinion that the arrangement able to make the sort of evidence on which Newton rested; by which the stability of the Solar System is secured is not and the sentence selected by Mr. Whewell as ' pointed at,' the work of chance; that “ a primitive cause has directed coupled with the remark specially made on that sentence, the planetary motions." This author however, having ar- has rather the appearance of being pointed at with approbarived, as we have done, at this conviction, does not draw tion. With regard to the assertion that Laplace propounded from it the conclusion which has appeared to us so irresis- the nebular theory as a primitive cause, it is true that he did tible, that “the admirable arrangement of the Solar System so in his own sense of the words. Mr. Whewell means by eannot but be the work of an intelligent and most power- primitive cause a first cause, as those words are usually ful Being." He quotes these expressions, which are those understood: and he asks (and the question would have of Newton, and points at them as instances where that been much to the purpose if Laplace had really meant the great philosopher had deviated from the method of true same thing as liimself by the words primitive cause), · Was philosophy. He himself proposes an hypothesis concerning man, with his thought and feeling, his powers and hopes, ihe nature of the primitive cause, of which he conceives the his will and conscience, also produced as an ultimate result existence to be thus probable.'

of the condensation of the solar atmosphere?' Bui Laplace Here are two assertions:-1, That it is the doctrine of an speaks as follows: 'Quelle est cette ccuse primitivej'exintelligent Creator which Laplace points at as a deviation poserai sur celà, dans la note qui termine cette ouvrage, une from true philosophy ; 2, That Laplace proposes bis nebu. hypothèse,' &c. And in the very first words of this note lar hypothesis as a primitive cause. We pay a writer of

Laplace evidently thunght that by mechanical causes Newtou meant Mr. Whewell's character the compliment of inserting here what we now call a cond causes. See the refrence just made. matter which would more appropriately appear in a review

+ Newton's Schobium does not seem to us to do any such thing; but ibat in

not the question. Laplace's approval or disapproval is of course to be applied of his work: and we deny that Laplace has been well I to his own interpretation of Newton's meaning, not to ours,

we find, ‘On a, pour remonter à la cuuse des mouvemens are certain and those which are probable (Laplace confined primitifs du système planelaire,' &c. This then is what himself to the former), are aciually existing in the Solar Laplace understood by primitive cause, a cause of the System: consequenily this hypothesis, though subject to primitive motions ;-an improper use of language, if the serious difficulties, deserves atientive consideration, as often reader pleases; but when a man puts his own meaning on as any new knowledge of the constituent parts of our system his own words, no one has a right to fix the consequences shall render a reference to it likely to produce evidence on of another meaning upon him.

one side or the other. As a substitute for intelligent creaWe now proceed to the nebular theory, which is a con tive power, if such a thing were intended, it would do no jecture proposed with much doubt by Laplace, as a possible better than any other; for, as Mr. Whewell observes, a man explanation of the manner in which the motions of the with will, power, and conscience, cannot be admitted to be several planets obtained those remarkable resemblances a necessary consequence of the cooling of a nebulous aimowhich are found to subsist, without making the inquiry ex- sphere. Nevertheless, as exhibiting a possible mode in tend to anything except their motions. All the planets which the Creator of mind and maiter made the laws of move in one direction round the sun, and their satellites formation resemble those of continuation, as far as the momove in the same direction round themselves; those that tions of ihe system are concerned, this hypothesis is strikingly are known to revolve round their axes (and the contrary has explicative of what we really see. But even if we were to been proved of no one of them) also revolve in the same take it to be a true explanation, it would only be one step direction, and their equators are not much inclined to their of the ascent, and the next question would be, what higher orbits. The excentricities of the planets and satellites are process distributed the parts of this nebulous mass in such in nu case very large, and generally very small; and the a manner as to place those outermost which were fit to form inclinations of their orbits to one another are generally small. a planet so distant from the source of light and heat as Many nebulæ in the heavens appear, when examined, to Uranus, and to support the appropriate forms of animal and consist of a bright nucleus surrounded by nebulous matter; vegetable life which analogy would induce us to suppose in others it is found that the apparently nebulous matter must exist there. consists of stars. This gave Laplace the idea that our Sys The history of astronomy teaches us that the system in tem might originally, that is, previously to the establishment which we live has not undergone any apparent change for of its present order, have been a large nebula of which the more than 2000 years; and, on inquiring into the connection sun was at the centre. Imagine a large nebulous mass in which exists between one planet and another, or the laws of a state of revolution, with a solid or at least less nebulous gravitation, it is found that so far as their mutual actions centre, round which it revolves: call this central nucleus are concerned, there is no reason why any change ever the sun. Assume the ordinary laws of matter to be true of should take place. If the central body were the only one this nebulous mass; and also that it extends as far as such which attracted the rest, and as long as the laws of matter an atmosphere can do; namely, until the attraction of the remained unaliered, it is certain that nothing could alter the whole upon particles at the equator is equal to the centri- revolutions of a system of planets, unless two orbits interfugal force of those particles. If condensation should secled, and the planets of those orbits happened to come to begin to take place, arising from loss of heat, the mass the intersecting part at the same time, and to strike each would revolve more and more rapidly as it was condensed other. But the planets are subject to the action of each into less and less space; but it does not follow that the other as well as to that of the sun, and no instant elapses equatorial particles would fall in towards the centre: they without every orbit undergoing a slight change from every are balanced by the equality of the centripetal and centri one of the planets of the other orbits. Jupiter alone profugal forces; and might form a ring round the rest of duces on the earth's orbit in one year more change than we the mass.

If the process were conducted with great have any right to say all the comets put together would do regularity, this ring and the mass of vapour might undergo in a hundred. And yet the system not only continues withcontinual condensation together, until the increasing velo- out any sensible change, but, one circumstance alone excity of rotation prevented the formation of the ring from con- cepted, to which we shall presently allude, is demonstrably tinuing. The departures from complete regularity which formed to continue for a most enormous length of time, unmight exist in the mass might cause disturbances in the less some new action should arise, or some external cause formation of the rings, which might end in there being one begin to operate. As it is sometimes stated that a complete or more (not many) permanently revolving round the rest mathematical demonstration has been given of the eterna: of the mass condensed into a solid body, in the manner of stability of the Solar System, so far as the mutual actions of Saturn and its rings. Such regular formation however its parts are concerned-an assertion which is altogether inmight be rarely continued long enough; and if the rings correct--it may be worth while to enter a little on the details got broken, each ring would become several masses, which of this subject. would revolve nearly at the same distance, and nearly with The disturbing forces of the planets on each other cannot the same velocity: such a result is seen in the four small I have their effects calculated all at once; but each force must planets. But as, generally speaking, these masses would, be divided into an infinite series of terms, the first of which by irregularities in their velocities, be combined into one* contains all the terms of the first dimension, the second all at last, each broken ring would form a new nebulous mass, those of ihe second, and so on. Of all these terms each is revolving round the diminished central nucleus: and if a much less in its effect than the preceding; so that in fact number of such masses were formed, those nearer to the the first two dimensions are all that produce any sensible central mass would move with the greater velocity, and effect in any time which it is worth while to consider. Ocwould be both smaller and denser than the external ones: casionally ii happens that terms of the third and fourth dithe first circumstance certainly, the second and third most mensions have been required to be used, but almost all the probably. Again, each mass would have a motion of revo sensible perturbations of the system depend on terms of the lution in the same direction (Motion, DIRECTION OF) as first two orders. As far as any effects arising from such the motion round the primary; for when the ring becomes | terms are concerned, Lagrange and Poisson are admitted on broken, its internal parts have a somewhat more rapid all bands to have demonstrated the stability of the Solår motion than the external ones, which would give the motion System: and considering the nature of the process employed, of rotalion noticed. And the rotations thus created in the and there being no appearance of any circumstance which internal masses would probably be greater than those in looks likely to lead to a different result in any of the rethe external masses. The orbits of the masses would ne- maining terms of the disturbing forces, it may be highly cessarily be nearly circular, and not much inclined to each probable that a further investigation would show the same other: but for irregularities, quite circular, and in the same thing, if all the dimensions of the disturbing forces were plane. In each of the nebulous masses, thus detached and employed. Sir J. Lubbock (Phil. Mag., February, 1831) revolving, condensation might again give rings or satellites has pointed out the forms which further investigation would or both; but in all probability ihe external masses would apparently produce, and which would (unless a detailed inget more satellites than the internal ones: the orbits of the vestigation should lead to something not discoverable à satellites must be also nearly circular, and not much in- priori) bear out as certain what we have just stated to be clined. All the preceding circumstances, both those which probable. But thongh all the presumptions lie on the side • If any number of masses, cnpable of cchering, revolve in oibits so near

of those who would assert the proposition absolutely of all to one amilier that they must cohere when they eine to their minimum im. dimensions of the disturbing force, it is not yet time to say tance, no:hing but an absolute and mathematical cquality in the maken volo: I that it is a certain maihematical consequence of the theory cities can keep them permanently asunder; the smallest inequality must at last bring them all togotbor,

of gravitation,

When the effects of preturbation are examined, as far as the future discovery. It is to be remembered that no science second dimension of the disturbing force, it appears that the has drawn out so much of mathematical talent, or indirectly immense mass of the sun compared with that of any planet, excited such an influence upon other branches of physical the great distance of the planets from each other as com research, as the application of the theory of gravitation to pared with their amounts of departure from spherical form, the development of the planetary motions. ihe small excentricities and inclinations of their orbits, and For more detail upon the subject, in a popular manner, their motions being all in one direction, give the following the English reader may consult Sir John Herschel's mathematical consequences of the law of attraction: * Treatise on Astronomy,’ in the Cabinet Cyclopædia, or Mrs. First, the longest or major axes of the planets' orbits are not Somerville's “Treatise on the Physical Sciences.' subject to any slow variations of very long period; all their SOLA'RIO, ANTONIO DE, called ' Il Zingaro,' or the variations being excessively small, and soon destroyed by Gipsy, was born in 1382, at Chivita, in the Abruzzi, ac the production of contrary variations. It is very often stated cording to Dominici (Vite de Pittori Napolitani), but others that the major axes are subject to no variation ; this is to be have contended that he was a Venetian. He was a gipsy understood only of seculur variation (or of very long period). by birth, and in his youth was a sort of itinerant blacksmith. One year is not precisely the same as another to any frac- He was not a mere tinker, a mender of kettles and saucetion of a second; but the average year of one long period is pans, for he is said to have been admitted into the house of precisely the same as that of another; or at least the mean ihe painter Colantonio del Fiore at Naples, on account of years of the two periods become more nearly equal the his skill in making implements of iron. Nearly the same longer the periods are made. But the excentricities and in-story is related of Solario as of Matsys, the blacksmith of clinations are subject to long periodic alterations, the times Antwerp. [Matsys.) Solario fell in love with the daughter of of ibeir recurrences not being exactly settled, from the diffi- Colantonio, and she fell in love with him. Solario made pro. culty of their determination. How then is it known that posals, but Colantonio said that he would never consent ihat they are periodic? For instance, the excentricity of the his daughter should marry any one but a painter of reputaEarthi's orbit is subject to a yearly diminution of .00004, its tion at least equal to his own. The gipsey was not to be thus value in 1801 being .017. Had this diminution been an got rid of; he asked to be allowed ten years to study the art, increase, as it is in Mercury and Jupiter, it might à priori and Colantonio, to satisfy his daugliter, assented. Solario appear possible that this increase should continue until the became a pupil of Lippo Dalmasi at Bologna, with whom orbit (preserving the same major axis) should be so elon- he remained six or seven years, and afterwards travelled gated that the ultimate approach to and recession from the through the chief towns of Italy in order to study the works sun should give our planet the alternate climates of Mer- of other masters. In rather more than nine years he recury and Mars, and thus no doubt destroy it as the abode turned in disguise to Naples, and having presented to the of beings constituted like ourselves. It is found however queen of Naples a picture of the Virgin, with the infant that the following relation must exist :-If at any one mo- Jesus crowned by angels, and also been permitted to paint ment the square of the excentricity of each planet be multi a portrait of the queen, Colantonio was then invited to view plied by its mass and the square root of its mean distance the productions of the unknown artist, of which he exfrom the sun (represented in numbers), the sum of all these pressed the highest admiration. Solario then discovered products must be the same as it was at any moment past, or himself, and soon afterwards became the son-in-law of Colwill be at any moment future. And if in each product the antonio

. His reputation was immediately established, and tingent of the inclination to a fixed plane be substituted for he was much employed, especially at Naples, in painting the excentricity, the resulting equation is true. From such altar-pieces, and in decorating the walls of convents and relations as these, and others connected with them, it is other religious houses with frescoes. In the fine expression shown that so far as the mutual actions of the planets are of hi, heads, and in the richness and harmony of his colourconcerned, no one excentricity nor inclination can increase ing, he has been compared to Titian. He is also praised for indefinitely, but all their changes must be periodic, and the graceful action of his figures, but is said to be defective confined within rather small limits. The approach of the in the drawing of the hands and feet. Solario was also disecliptic to the equator, for instance, which amounts to about tinguished as an illuminator of manuscripts, especially half a second in a year (and which leads speculators sume Bibles. He died in 1455. Vasari has not included Solario times to talk about a past time when the ecliptic passed in his • Lives.' through the pole, and a future time when it will coincide (Dominici, Vite de' Pittori Napolitani ; Moschini, Me. with the equator), must stop long before the ecliptic reaches morie della Vita di Antonio de Solario, detto Il Zingaro, the equator, and attain a minimum inclination, after which Pittore Viniziano, Venezia, 1828.) the two will begin to separate; the whole oscillation being

SOLARIUM. [TROCHIDÆ.] less than three degrees. The whole result is summed up

SOLDA'NIA. [FORAMINIFERA, vol. X., p. 348.] thus: As far as terms of the second order (inclusive) in the SOLDERING, according to Dr. Ure (Dict. of Arts, &c.), disturbing forces, and as long as only the mutual attractions is ‘ the process of uniting the surfaces of metals, by the inof the planets act, there is a mathematical certainty that the tervention of a more fusible metal, which, being melted Solar System will remain in its present state, the elements upon each surface, serves, partly by chemical attraction, of the different orbits oscillating about certain mean values, and partly by cohesive force, to bind them together.' In from which they are never very distant: except only the accordance with this, which is the ordinary acceptation of longitudes of the nodes and perihelia, which change with the word soldering, a solder may be defined as a metallic velocities which are always very near to a certain mean cement employed to unite, by being fused between them, velocities. The probability is very small that the higher two pieces of metal. Such an explanation however, though dimensions of the disturbing forces would affect this result, correct in most cases, does not apply to every kind of solderand certainly only in a length of time to which the longest ing; a process having been recently introduced by which periods known are tritling in comparison.

pieces of metal may be perfectly united without the interThis last point however is of the less importance, since it position of solder. has become highly probable, within the last few years, that In the ordinary mode of soldering, the alloy used as a solder an external cause does exist, which must, unless ihere be a must be more fusible than the metal or metals which are to counteracting force of which we know nothing, in time be united, and must have a strong affinity for them. The sol. cause the destruction of the System. If the planets move der usually contains a large proportion of the metal to which in any medium which resists their motions, however little, it is to be applied, in combination with some more easily the consequence must be a gradual diminution of their fusible metals. To insure perfect melallic union between mean distances from the sun, and a gradual increase of the solder and the surfaces to which it is applied, it is essentheir relocities, ending in their absolutely falling into the tial that they be made perfectly clean and free from oxide, sun. For the presumption in favour of the actual existence and that the atmosphere be excluded during the operation, of such a resisting medium, see Comer, p. 394. This re in order to prevent the formation of any oxide while the tarding agent seems to show a rapid effect upon so at- process is going on. This is effected in various ways, but tenuated a mass as Encke's comet, though thousands of most commonly by the use of borax, sal ammoniac, or rosin, yeurs have elapsed without its producing any sensible effect either mixed with the solder or applied to the surfaces to upon the planets. Little as it may concern us directly, be joined. Mr. Thomas Spencer, of Liverpool, has recently these speculations have an interest, both as to the glimpse made some interesting experiments, the results of which they give of the possible destiny of our System, and froin are given in a paper. On the Theory and Practice of Soltheir association with the history of past and the hope of dering Metals,' which was read before the Liverpool PolyP C., No. 1384,

Vol. XXII.-2 D

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