’Twas a pretty many Years ago that I chanc’d to light upon Athanaſius Kircher’s Book, call’d The Ecſtatick Journey, which treats of the nature of the Stars, and of the Things that are to be found in the Superficies of the Planets: I wondered to ſee nothing there of what I had often thought not improbable, but quite other Things, nothing but a Heap of idle unreaſonable Stuff: which I was the more confirm’d in, when, after the writing of the former part, I ran over the Book again. And I thought mine were very conſiderable and weighty Matters if compar’d with Kircher’s. That other People may be ſatisfied in this, and ſee how vainly thoſe, who caſt off the only Foundations of Probability in ſuch Matters, which we have all the way made uſe of, pretend to philoſophize [102]in this caſe, I think it will not be beſide the Purpoſe to beſtow ſome few Reflections upon that Book.

Kircher’s Journey in Ecſtacy examin’d. That ingenious Man ſuppoſing himſelf carried by ſome Angel thro’ the vaſt Spaces of Heaven, and round the Stars, tells us, he ſaw a great many things, ſome of which he had out of the Books of Aſtronomers, the reſt are the Product of his own Fancy and Thoughts. But, before he enters upon his Journey, he lays down theſe two Things as certain; that no Motion muſt be allowed the Earth, and that God has made nothing in the Planets, no not ſo much as Herbs, which has either Life or Senſe in it. Leaving then the Syſtem of Copernicus, he chuſes Tycho for his Guide. But when he ſuppoſes all the fix’d Stars to be Suns, and round each of them places their Planets, here (againſt his Will I ſuppoſe) he has unawares made an infinite number of Copernican Syſtems. All which, beſide their own Motion, he abſurdly makes to be carried, with an incredible ſwiftneſs, in twenty four Hours round the Earth. Since moſt [103]of theſe Worlds are out of the Reach of any Man’s ſight, as he owns they are, I cannot think for what purpoſe he makes ſo many Suns to ſhine upon deſolate Lands (like our Earth in every thing, he ſays, only that they have neither Plants nor Animals) where there’s no one to whom they ſhould give light. And from hence he ſtill falls into more and more Abſurdities. And becauſe he could find no other uſe of the Planets, even in our Syſtem, he is forc’d to beg Help of the Aſtrologers; and would have all thoſe vaſt Bodies made upon no other account than that the whole Univerſe might be preſerved and continue ſecure by their means, and that they might govern the Mind of Man by their various and regular Influences. Accordingly, to gratify Aſtrology, he ſays that Venus was the moſt pleaſant Place, every thing fine and handſome, its Light gentle, its Waters ſweet and purling, and it ſelf beſet all about with ſhining Chryſtals. In Jupiter he found wholeſome and ſweet Gales, delicate Waters, and a Land ſhining like Silver. For from [104]theſe two Planets it ſeems, Men have all that is happy and healthful poured down upon them; and all that renders them handſome and lovely, wiſe and grave, is owing to their Influences. Mercury had I don’t know what Airineſs and Briskneſs in it; whence Men derive, when they are firſt born, all their Wit and Cunning. Mars was nothing but infernal, ſtinking, black Flames and Smoke: and Saturn was all melancholy, dreadful, naſty, and dark: for theſe are the Planets (I don’t know why, but all Fortune-tellers hate them) that bring all the Plagues and Miſchiefs that we feel upon us, and would exerciſe their Spite ſtill more, unleſs they were ſometimes mitigated and corrected by the benign and kind Influences of the other Planets. All this and ſuch like Stuff his Genius teaches him. Which he makes give a ſerious Anſwer to this idle Queſtion, Whether a Jew or Heathen could be duly and rightly baptized in the Waters of Venus? Of him too he learns that the Heaven of the fix’d Stars is not made of ſolid Matter, but of a thin fluid, [105]wherein an innumerable company of Stars and Suns lie floating here and there, not chain’d down to any Place, (thus far he’s in the right) and deſcribing in the Space of a Day theſe prodigious Circles round the Earth. He forgets here, if there were ſuch a Motion, with what an incredible ſwiftneſs they would fly off from every part of their Orbits. But I ſuppoſe the Intelligences that he has plac’d in them are to take care of that, thoſe Angels that preſide over, and regulate their Motions. And in that he follows a company of Doctors that harbour’d that idle fancy of Ariſtotle upon no Account or Conſideration. But Copernicus has freed thoſe Intelligences of all that Labour and Trouble, only by bringing in the Motion of the Earth: which, if upon no other Account, every one that is not blind purpoſely, muſt own to be neceſſary upon this. I dare ſay Kircher, if he had dar’d freely to ſpeak his Mind, could have afforded us better ſort of Things than theſe. But when he could not have that liberty, I think he might as well have [106]let the whole Matter alone. But enough of this; let’s have have done with this famous Author: And now that we have ventur’d to place Spectators in the Planets, let us examine each of them, and ſee what their Years, Days, and Aſtronomy are.

The Syſtem of the Planets in Mercury. To begin with the innermoſt and neareſt the Sun: We know that Mercury is three times nearer that vaſt Body of Light than we are. Whence it follows that they ſee him three times bigger, and feel him nine times hotter than we do. Such a degree of Heat would be intolerable to us, and ſet afire all our dry’d Herbs, our Hay and Straw that we uſe. And yet there is no doubt but that the Animals there, are made of ſuch a Temper, as to be but moderately warm, and the Plants ſuch as to be able to endure the Heat. The Inhabitants of Mercury, it’s likely, have the ſame opinion of us that we have of Saturn, that we muſt be intolerably cold, and have little or no Light, we are ſo far from the Sun. There’s reaſon to doubt, whether the Inhabitants of Mercury, tho’ they live ſo much nearer [107]the Sun, the Fountain of Life and Vigour, are much more airy and ingenious than we. For if we may gueſs at them by what we ſee here, we ſhall not be obliged to grant it. The Inhabitants of Africa and Braſil, that have got for their Share the hotteſt Places in the Earth, being neither ſo wiſe nor ſo induſtrious as thoſe that belong to colder and more temperate Climates; they have ſcarce any Arts or Knowledge among them; and thoſe of them that live upon the very Shore, underſtand little or no Navigation. Nor can I be willing to make all that vaſt number that muſt inhabit thoſe two large Planets, Jupiter and Saturn, and have ſuch noble Attendance, mere dull Blockheads, or without as much Wit as our ſelves, tho’ they are ſo far more diſtant from the Sun. The Aſtronomy of thoſe that live in Mercury, and the appearance of the Planets to them, oppoſite at certain times to the Sun, may be eaſily conceived by the Scheme of the Copernican Syſtem in the former Part. At the times of theſe Oppoſitions Venus and the Earth muſt needs [108]appear very bright and large to them. For if Venus ſhines ſo gloriouſly to us when ſhe is new and horned, ſhe muſt neceſſarily in oppoſition to the Sun, when ſhe is full, be at leaſt ſix or ſeven times larger, and a great deal nearer to the Inhabitants of Mercury, and afford them Light ſo ſtrong and bright, that they have no reaſon to complain of their want of a Moon. What the Length of their Days are, or whether they have different Seaſons in the Year, is not yet diſcovered, becauſe we have not yet been able to obſerve whether his Axis have any inclination to his Orbit, or what Time he ſpends in his diurnal Revolution about his own Axis. And yet ſeeing Mars, the Earth, Jupiter and Saturn, have certainly ſuch Succeſſions, there’s no reaſon to doubt but that he has his Days and Nights as well as they. But his Year is ſcarce the fourth part ſo long as ours.

The Inhabitants of Venus have much the ſame Face of Things as thoſe in Mercury, only they never ſee him in oppoſition to the Sun, which is occaſioned [109]by his never removing above 38 degrees, or thereabouts, from it. The Sun appears to them larger by half in his Diameter, and above twice in his Circumference, than to us: and by conſequence affords them but twice as much Light and Heat, ſo that they are nearer our Temperature than Mercury. Their Year is compleated in ſeven and a half of our Months. In the Night our Earth, when ’tis on the other ſide of the Sun from Venus, muſt needs ſeem much larger and lighter to Venus than ſhe doth ever to us; and then they may eaſily ſee, if their Eyes be not weaker than ours, our conſtant Attendant the Moon. I have often wonder’d that when I have view’d Venus when ſhe is neareſt to the Earth, and reſembled an Half-moon, juſt beginning to have ſomething like Horns, through a Teleſcope of 45 or 60 Foot long, ſhe always appeared to me all over equally lucid, that I can’t ſay I obſerved ſo much as one Spot in her, tho’ in Jupiter and Mars, which ſeem much leſs to us, they are very plainly perceiv’d. [110]For if Venus had any ſuch Thing as Sea and Land, the former muſt neceſſarily ſhow much more obſcure than the other, as anyone may ſatisfy himſelf, that from a very high Mountain will but look down upon our Earth. I thought that perhaps the too brisk Light of Venus might be the occaſion of this equal appearance; but when I uſed an Eye-glaſs that was ſmok’d for the Purpoſe, it was ſtill the ſame Thing. What then, has Venus no Sea, or do the Waters there reflect the Light more than ours do, or their Land leſs? Or rather (which is moſt probable in my Opinion) is not all that Light we ſee reflected from an Atmoſphere ſurrounding Venus, which being thicker and more ſolid than that in Mars or Jupiter, hinders our ſeeing any thing of the Globe it ſelf, and is at the ſame time capable of ſending back the Rays that it receives from the Sun? For it is certain that if we looked on the Earth from the outſide of the Atmoſphere, we ſhould not perceive ſuch a difference as we do from a Mountain; but by reaſon of the interpoſed [111]Atmoſphere, we ſhould obſerve very little Diſparity between Sea and Land. ’Tis the ſame Thing that hinders us from ſeeing the Spots in the Moon as plain in the Day as in the Night, becauſe the Vapours that ſurround the Earth being then enlighten’d by the Rays of the Sun, are an Impediment to our Proſpect.

In Mars. But Mars, as I ſaid before, has ſome Parts of him darker than other ſome. By the conſtant Returns of which his Nights and Days have been found to be of about the ſame length with ours. But the Inhabitants have no perceivable Difference between Summer and Winter, the Axis of that Planet having very little or no Inclination to his Orbit, as has been diſcover’d by the Motion of his Spots. Our Earth muſt appear to them almoſt as Venus doth to us, and by the Help of a Teleſcope will be found to have its Wane, Increaſe, and Full, like the Moon: and never to remove from the Sun above 48 Degrees, by whoſe Diſcovery they ſee it, as well as Mercury and Venus, ſometimes paſs over the Sun’s Disk. They as ſeldom ſee [112]Venus as we do Mercury. I am apt to believe, that the Land in Mars is of a blacker Colour than that of Jupiter or the Moon, which is the reaſon of his appearing of a Copper Colour, and his reflecting a weaker Light than is proportionable to his diſtance from the Sun. His Body, as I obſerved before, tho’ farther from the Sun, is leſs than Venus. Nor has he any Moon to wait upon him, and in that, as well as Mercury and Venus, he muſt be acknowledged inferiour to the Earth. His Light and Heat is twice, and ſometimes three times leſs than ours, to which I ſuppoſe the Conſtitution of his Inhabitants is anſwerable.

Jupiter and Saturn the moſt eminent of the Planets both for bigneſs and attendants. If our Earth can claim pre-eminence of the fore-mention’d Planets, for having a Moon to attend upon it, (for its Magnitude can make but a ſmall difference) how much Superiour muſt Jupiter and Saturn be to thoſe three and the Earth alſo? For whether we conſider their Bulk, in which they far exceed all the others, or the Number of Moons that wait upon them, it’s very probable that they are the chief, the [113]primary Planets in our Syſtem, in compariſon with which the other four are nothing, and ſcarce worth mentioning. For the eaſier Conception of their vaſt Diſparity, I have thought fit to add a Scheme of our Earth, with the Moon’s Orbit, and the Globe of the Moon itſelf, and the Syſtems of Fig. 3. Jupiter and Saturn, where I have drawn every thing as near the true Proportion as poſſible. Jupiter you ſee is adorned with four, and Saturn with five Moons, all placed in their reſpective Orbits. The Moons about Jupiter we owe to Galilæo, ’tis well known: and any one may imagine he was in no ſmall Rapture at the Diſcovery. The outermoſt but one, and brighteſt of Saturn’s, it chanc’d to be my lot, with a Teleſcope not above 12 foot long, to have the firſt ſight of in the Year 1655. The reſt we may thank the induſtrious Caſſini for, who uſed the Glaſſes of Joſ. Campanus’s grinding, firſt of 36, and afterwards of 136 foot long. He has often, and particularly in the Year 1672, ſhew’d me the Third and Fifth. The Firſt and Second he gave [114]me notice of by Letters in the Year 1684; but they are ſcarce ever to be ſeen, and I can’t poſitively ſay, I had ever that Happineſs; but am as ſatisfied that they are there, as if I had; not in the leaſt ſuſpecting the Credit of that worthy Man. Nay, I am afraid there are One or Two more ſtill behind, and not without reaſon. For between the Fourth and Fifth there’s a Diſtance not at all proportionable to that between all the others: Here, for ought I know, there may be a Sixth; or perhaps there may be another without the Fifth that may yet have eſcaped us: for we can never ſee the Fifth but in that part of his Orbit, which is towards the Weſt: for which we ſhall give you a very good reaſon.

Perhaps when Saturn comes into the Northern Signs, and is at a good height from the Horizon (for at the writing of this he is at his loweſt) you may happen to make ſome new Diſcoveries, good Brother, if you would but make uſe of your two Teleſcopes of 170 and 210 Foot long; the longeſt, and the beſt I believe now [115]in the World. For tho’ we have not yet had an opportunity of obſerving the Heavens with them (as well by reaſon of their Unwieldineſs, as for the Interruption of our Studies by your Abſence) yet I am ſatisfied of their Goodneſs by our trial of them one Night, in reading a Letter at a vaſt diſtance by the Help of a Light. I cannot but think of thoſe times with Pleaſure, and of our diverting Labour in poliſhing and preparing ſuch Glaſſes, in inventing new Methods and Engines, and always puſhing forward to ſtill greater and greater Things. But to return to the Figures, of which there remains ſomething further to be ſaid.

The proportion of the Diameter of Jupiter, and of the Orbs of his Satellites, to the Orbit of the Moon round the Earth. I have there made the Diameter of Jupiter about two third parts of our diſtance from the Moon: for the Diameter of Jupiter is above twenty times bigger than that of the Earth; which is about a thirtieth part of the Moon’s diſtance. The Orbit of the outermoſt of Jupiter’s Satellites is to that of the Moon round the Earth, as 8 and ½ is to 1. And each of theſe Moons, by the Shadow they make upon Jupiter, [116]cannot be leſs than our Earth. Their The Periods of Jupiter’s Moons. Periods, that I may not omit them, are according to Caſſini’s Account theſe. That of the inmoſt is one day, 18 hours, 28 minutes, and 36 ſeconds. The Second ſpends 3 days, 13 hours, 13 min., 52 ſeconds in going round him. The Third 7 days, 3 hours, 59 min., 40 ſec. The Fourth 16 days, 18 hours, 5 min., 6 ſec. The Diſtance of the innermoſt from Jupiter himſelf is 2⅚ of his Diameters. That of the Second is 4 and a half: Of the Third 7 and one ſixth part: Of the Fourth 12 and two thirds, of the ſame And Saturn’s. Diameters. The Innermoſt of Saturn’s Satellites moves round him in 1 day, 21 hours, 18 min., 31 ſec. The Second in 2 days, 17 hours, 41 min., 27 ſec. The Third in 4 days, 13 hours, 47 min., 16 ſec. The Fourth in 15 days, 22 hours, 41 min., 11 ſec. The Fifth in 79 days, 7 hours, 53 min., 57 ſec. Their Diſtances from the Center of Saturn are, that of the firſt almoſt one, that is 39 fortieth parts of the Diameter of his Ring; that of the ſecond one and a quarter of thoſe Diameters; [117]of the third one and three quarters of them; of the fourth four, or according to my Calculation, but 3 and a half; of the 5th 12, which were found with vaſt Pains and Labour.

Now can any one look upon, and compare theſe Syſtems together, without being amazed at the vaſt Magnitude and noble Attendance of theſe two Planets, in reſpect of this little Earth of ours? Or can they force themſelves to think, that the wiſe Creator has diſpoſed of all his Animals and Plants here, has furniſh’d and adorn’d this Spot only, and has left all thoſe Worlds bare and deſtitute of Inhabitants, who might adore and worſhip him; or that all thoſe prodigious Bodies were made only to twinkle to, and be ſtudied by ſome few perhaps of us poor Mortals?

This proportion true according to all modern Obſervations. I do not doubt but there will be ſome who will think we are very much miſtaken about the Magnitude of theſe Planets. For will you pretend to make them who are taken up in admiring the Largeneſs of this Globe, [118]its multitude of Nations, Cities, and Empires; can you pretend I ſay to make them ever believe that there are Places in compariſon of which the Earth is as inconſiderable as this Figure would make it? But they ought to be inform’d, that theſe Proportions are thoſe which the beſt Aſtronomers of this Age have agreed upon. For if the Earth be diſtant from the Sun ten or eleven thouſand of its own Diameters, according to the Accounts of Monſieur Caſſini in France, and Mr. Flamſted in England, wherein they made uſe of very exact Obſervations of the Parallaxes of Mars; or if, according to a very probable Conjecture of mine, it be diſtant twelve thouſand, then the Magnitudes of the other Orbs will very near anſwer the Proportions here ſettled.

The apparent magnitude of the Sun in Jupiter, and a way of finding what Light they there enjoy. But to return to Jupiter. The Sun appears to them who are upon it five times leſs than to us, and conſequently they have but the five and twentieth part of the Light and Heat that we receive from it. But that Light is not ſo weak as we imagine, as is [119]plain by the Brightneſs of that Planet in the Night; and alſo from hence, that when the Sun is ſo far eclipſed to us, as that only the 25th part of his Disk remains uncovered, he is not ſenſibly darken’d. But if you have a mind exactly to know the Quantity of Light that Jupiter enjoys, you may take a Tube of what Length you pleaſe. Let one end of it be cloſed with a Plate of Braſs, or any ſuch thing, in the middle of which there muſt be a Hole, whoſe Breadth muſt have the ſame proportion to the length of the Tube, as the Chord of 6 Minutes bears to the Radius; that is, about as one is to 570. Let the Tube be turned ſo to the Sun, that no Light may fall upon a white Paper placed at the End of it, but what comes through the little Hole at the other end of the Tube. The Rays that come through this will repreſent the Sun upon the Paper of the ſame Brightneſs that the Inhabitants of Jupiter ſee it in a clear Day. And if removing the Paper you place your Eye in the ſame Place, you will ſee the Sun of the ſame Magnitude and [120]Brightneſs as you would were you in Jupiter.

And in Saturn. If you make the Hole twice as little in breadth, you will ſee the ſame in Saturn. And altho’ his Light be but the hundredth part of ours, yet you ſee it makes him ſhine tolerably bright in a dark Night. But in both theſe Planets, if there ever be any cloudy Days, it muſt be very dark in compariſon of us; yet without doubt the Inhabitants have no more reaſon to complain of the want of Light, than our Owls and Batts, to whom the Twilight or the Night itſelf is more agreeable than the Brightneſs of the Day.

In Jupiter their days are five Hours. But it’s a little ſtrange, that when Jupiter is ſo much bigger than our Planet, their Days and Nights ſhould be but five of our Hours. By this we may ſee that Nature has not obſerv’d that proportion that their Bulk ſeems to require, ſeeing in Mars the Days are very little different from ours. But in the length of their Years, that is, in the Revolution of the Planets round the Sun, there is an exact proportion to [121]their diſtances from the Sun followed. For as the Cubes of their Diſtances, ſo are the Squares of their Revolutions, as Kepler firſt ſound out. Which proportion the Moons of Jupiter and Saturn keep in their Courſes round thoſe Always of the ſame length. Planets. As the Years and Days in Jupiter are different from ours in this reſpect, ſo are the Days in another; namely, that they are all of the ſame length. For they there enjoy a perpetual Equinox, their Axis having little or no inclination to their Orbit, as the Earth’s has, as has been diſcovered by Teleſcopes. The Countries that lie near their Poles have little or no Heat, by reaſon the Rays of the Sun fall ſo obliquely upon them; but then they are freed from the Inconveniency that ours are troubled with, of tedious long half-year Nights, and have the conſtant returns of Day and Night every five Hours. Indeed ſuch ſhort Days would not be agreeable to us, but we think our ſelves much better done by, that ours are more than twice as long, tho’ upon no other account, but that whatever is our own, we are apt to imagine, muſt be beſt. [122]

The reſt of the Planets are ſo near the Sun (Mars himſelf never being above 18 degrees from it) that in Jupiter they have the ſight only of Saturn. But we cannot deny but that their four Moons ſtand them in greater ſtead than our one doth us, if ’twere only that they ſeldom know any ſuch Thing as to be without Moonſhiny Nights. And they are of great Advantage to them, as we ſaid before, in their Navigation, if they have any ſuch thing. Not to mention the pleaſant Sights of their frequent Conjunctions and Eclipſes, Things that they are ſeldom a Day without.

Saturn enjoys all thoſe Pleaſures and Advantages in a ſtill higher Degree, as well for his five Moons, as for the delightful Proſpect that the Ring about him affords his Inhabitants Night and Day. But we will give an account of their Aſtronomy, as we have done of the reſt of the Planets.

They ſee the fix’d Stars juſt as we do. And firſt of all we ſhall obſerve what we might have remark’d before, but which will be more ſtrange here, that the fix’d Stars appear to them of [123]the ſame Figure and Magnitude, and with the ſame degree of Light that they do to us: and this, by reaſon of their immenſe diſtance, of which we ſhall have occaſion to ſpeak by and by. In compariſon with which the Space that a Bullet-ſhot out of a Cannon could travel in 25 Years, would be almoſt nothing.

Their Aſtronomers have all the ſame Signs of the Bear, the Lion, Orion, and the reſt, but not turning upon the ſame Axis with us: for that’s different in all the Planets.

As Jupiter can ſee no Planet but Saturn, ſo Saturn knows of no Planet but Jupiter; which appears to him much as Venus doth to us, never removing above 37 Degrees from the Sun. The Length of their Days I cannot determine: But if from the Diſtance and Period of his innermoſt Attendant, and comparing it with the innermoſt of Jupiter’s, a Man may venture to give a Gueſs, they are very little different from Jupiter’s, 10 Hours or ſomewhat leſs. But whereas in Jupiter theſe are equally divided between [124]Light and Darkneſs, the Inhabitants of Saturn muſt perceive a more ſenſible difference than we, eſpecially between Summer and Winter. For our Axis inclines to the Plane of the Ecliptick but 23 degrees and a half, but there’s above 31. Upon this Account his Moons muſt decline very much from the Path that the Sun ſeems to move in, and his Inhabitants can never have a full Moon but juſt at the Equinoxes; Two of which fall out in 30 of our Years. ’Tis this Poſition of the Axis too that is the Cauſe of thoſe delightful Appearances, and wonderful Proſpects that its Inhabitants enjoy: For the better underſtanding of which I ſhall draw a Figure of Saturn with his Ring about him: in which the Proportion between the Diameters of the Globe and Ring is as 9 to 4. And the empty Space between them is of the ſame Breadth with the Ring itſelf. All Obſervations conſpire to prove that That is of no great Thickneſs, altho’ if we ſhould allow it ſix hundred German Miles, I think, conſidering its Diameter, we ſhould not overdo the Matter.

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Suppoſe then, agreeable to what has been ſaid, the Globe of Saturn, Fig. 4. whoſe Poles are A, B. G N is the Diameter of the Ring, as you view it ſideways, repreſenting a narrow Oval. Thoſe that live about the Poles within the Arches C A D, E B F, each of which are 54 Degrees, (if the Cold will ſuffer any Body to live there) never have a Sight of the Ring. The Appearances of the Ring in Saturn. From all other parts it is continually to be ſeen for fourteen Years and nine Months, which is juſt half their Year. The other Half it is hid from their View. Thoſe then that dwell between the Polar Circle C D, and the Equator T V, all that time that the Sun enlightens the Part oppoſite to them, have every Night the Sight of a Piece of it H G L, much in the Shape of a ſhining Bow, which comes from the Horizon, but is darken’d in the Middle by the Shadow of Saturn G H, which reaches moſt commonly to the outermoſt Rim of it. But after Midnight that Shadow by little and little begins to move towards the right Hand to thoſe in the Northern, but the Left [126]to thoſe in the Southern Hemiſphere. In the Morning it diſappears, leaving behind it a Likeneſs indeed of a Bow, but much paler and weaker than our Moon is in the Day time. For they, as I ſaid before, have an Atmoſphere, or an Air ſurrounding them enlightened by the Sun. Otherwiſe Night and Day they would have their Ring, their Moons, and all the fix’d Stars, equally conſpicuous. Another thing that muſt make the Sight of their Ring very curious, is, that by ſome Spots in it, it is diſcover’d to turn round upon it ſelf: A thing that thoſe that are ſo near cannot but take notice of, when we that live at this Diſtance can deſcry a great Inequality, the inſide of it being brighter much than the outſide is. When the Shadow of the Globe falls upon that part of the Ring G H, the Shadow of the Ring at the ſame time darkens another Part of the Globe about P F, which otherwiſe would have the Sun upon it. So that there is always a Zone of the Globe P Y F E, ſometimes of a larger extent than at others, which is depriv’d of the Sight [127]both of the Sun and Ring for a conſiderable time, the latter of which hides ſome part of the Stars from it too. And certainly an amazing Thing it muſt be, all of a ſudden to have the Sun intercepted and to become as dark as Midnight, without ſeeing any Cauſe of ſuch an Accident. All which time their Moons are their only Comfort. The other half of the Year the Hemiſphere T B V enjoys the ſame Light that T A U before did, and then this undergoes thoſe long Eclipſes that That before ſuffer’d. At the Equinoxes, when the Sun is in the ſame Plane with the Ring, the Inhabitants of Saturn cannot well perceive it: no not even we with our Glaſſes, by reaſon of its Darkneſs. This happens when Saturn, view’d from the Sun, is advanced one and twenty degrees and a half in Virgo or Piſces, as I have ſhow’d formerly in my Syſtem of Saturn: Where there is an Account given of the Riſings of the Sun above the Ring, throughout all the Saturnian Year. [128]

With Saturn in this Scheme you have the Globes of the Earth and Moon drawn in their true proportion, to put you in mind again of a Thing worth remembring, viz. how very ſmall our Habitation is when compar’d with that Globe or the Ring about it. And now any one, I ſuppoſe, can frame to himſelf a Picture of the Night in Saturn, with two Arches of the Ring, and five Moons ſhining about, and adorning him. This then is what I had to ſay to the primary Planets.

We are now come a little lower, to make an enquiry into the Attendants of theſe Planets, eſpecially our own. And here we ſhall not only conſider their Aſtronomy, but ſhall alſo ſearch into their Furniture and Ornament, if they are found to have any ſuch thing, which we have deferred conſidering till now.

Very little to be ſaid of the Moon. And here one would think that when the Moon is ſo near us, and by the Means of a Teleſcope may be ſo nicely and exactly obſerv’d, it ſhould afford us Matter for more probable [129]Conjectures than any of the other remote Planets. But it is quite otherwiſe, and I can ſcarce find any thing to ſay of it, becauſe I have not a Planet of the ſame Nature before my Eyes, as in all the primary ones I have. For they are of the ſame kind with our Earth; and ſeeing all the Actions, and every thing that is here, we may make a reaſonable Conjecture at what we cannot ſee in thoſe Worlds.

The Guards of Jupiter and Saturn of the ſame nature with our Moon. But this we may venture to ſay, without fear, that all the Attendants of Jupiter and Saturn are of the ſame Nature with our Moon, as going round them, and being carried with them round the Sun juſt as the Moon is with the Earth. Their Likeneſs reaches to other Things too, as you’ll ſee by and by. Therefore whatſoever we can with reaſon affirm or conjecture of our Moon (and we may ſay a little of it) muſt be ſuppos’d with very little Alteration to belong to the Satellites of Jupiter and Saturn, as having no reaſon to be at all inferior to that.

The Moon hath Mountains. The Surface of the Moon then is found, by the leaſt Teleſcopes of about [130]three or four Foot, to be diverſified with long Tracts of Mountains, and again with broad Valleys. For in thoſe Parts oppoſite to the Sun you may ſee the Shadows of the Mountains, and often diſcover the little round Valleys between them, with a Hillock or two perhaps riſing out of them. Kepler from the exact roundneſs of them would prove that they are ſome vaſt work of the rational Inhabitants. But I can’t be of his mind, both for their incredible Largeneſs, and that they might eaſily be occaſioned by natural Cauſes. Nor can I find any thing like Sea there, tho’ he and many others are of the contrary Opinion I know. For thoſe vaſt Countries which appear darker than the other, commonly taken for and called by the Names of Seas, are diſcover’d with a good long Teleſcope, to be full of little round Cavities; whoſe Shadow falling within themſelves, makes them appear of that Colour: and thoſe large Champains there in the Moon you will find not to be always even and ſmooth, if you look carefully [131]upon them: neither of which two But no Sea. Things can agree to the Sea. Therefore thoſe Plains in her that ſeem brighter than the other Parts, muſt conſiſt, I ſuppoſe, of a whiter ſort of Matter than they. Nor do I believe Nor Rivers. that there are any Rivers, for if there were, they could never eſcape our Sight, eſpecially if they run between the Hills as ours do. Nor have they Nor Clouds. any Clouds to furniſh the Rivers with Water: For if they had, we ſhould ſometimes ſee one part of the Moon darkened by them, and ſometimes another, whereas we have always the ſame Proſpect of her.

Nor Air, and Water. ’Tis certain moreover, that the Moon has no Air or Atmoſphere ſurrounding it as we have. For then we could never ſee the very outermoſt Rim of the Moon ſo exactly as we do, when any Star goes under it, but its Light would terminate in a gradual faint Shade, and there would be a ſort of a Down as it were about it; not to mention that the Vapours of our Atmoſphere conſiſt of Water, and conſequently that where there are no Seas [132]or Rivers, there can be no Atmoſphere. This is that notable difference between the Moon and us that hinders all probable Conjectures about it. If we could but once be ſure that there were Seas and Rivers in it, it would be no weak Argument to prove that it has alſo all other Furniture which belongs to our Earth, and the Opinion of Xenophanes might be true, that it has its Inhabitants, Cities, and Mountains. But as ’tis, I cannot imagine how any Plants or Animals, whole whole nouriſhment comes from liquid Bodies, can thrive in a dry, waterleſs, parch’d Soil.

The Conjecture of its Plants and Animals very dubious. What then, is it credible that this great Ball was made for nothing but to give us a little Light in the Night-time, or to raiſe our Tides in the Sea? May there not be ſome People there that may have the Pleaſure of ſeeing our Earth turn upon itſelf, preſenting them ſometimes with a Proſpect of Europe and Africa, and then of Aſia and America; ſometimes half of it bright, and ſometimes full? And muſt all thoſe Moons round Jupiter and Saturn [133]be condemned to the ſame Uſeleſneſs? I do not know what to ſay concerning it, becauſe I know of nothing like them to found a Conjecture upon. And yet ’tis not improbable that thoſe great and noble Bodies have ſomewhat or other growing and living upon them, though very different from what we ſee and enjoy here. Perhaps their Plants and Animals may have another ſort of Nouriſhment there. Perhaps the Moiſture of the Earth there is but juſt ſufficient to cauſe a Miſt or Dew, which may be very ſuitable to the Growth of their Herbs. This I remember is Plutarch’s Opinion, in his Dialogue upon this Subject. For in our Earth a very little Water drawn from the Sea into Dew, and falling down again upon the Herbs, would be ſufficient for all our Needs, without any Rain or Showers. But theſe are mere Gueſſes, or rather Doubts, but yet they are the Jupiter’s and Saturn’s Moons turn always the ſame Side to them. beſt we can make of this, and all thoſe other Moons: for, as I ſaid before, they are all of the ſame nature, which is proved likewiſe by this, that as our [134]Moon can afford us the Sight never but of one Side of her, ſo they turn always the ſame Face to their primary Planets. It may perhaps ſeem ſtrange, how we ſhould come to know this; but ’tis no hard matter, after that Obſervation which I juſt now made, that the outermoſt of Saturn’s Moons can never be ſeen but when ſhe is on the Weſt-ſide of her Planet. The reaſon of which is plainly this, that one Side of her is darker, and does not reflect the Light ſo much as the other, which when it is turned towards us, we cannot ſee by reaſon of its weak Light. This always happening when ’tis Eaſt of him, and never on the other Side, is a manifeſt proof that ſhe always keeps the ſame Side toward Saturn. Now ſince the outermoſt of Saturn’s and our Moon carry themſelves thus to the Planets round which they move, who can well doubt it of all the reſt round Jupiter and Saturn? And there’s a very good reaſon for it, namely, that the matter of which thoſe Moons conſiſt, being heavier, and more ſolid on the Side that is averſe from us, than on [135]that which we have the Sight of, does conſequently fly with a greater force from the Centre of its Orbit: for otherwiſe, according to the Laws of Motion, it ſhould turn the ſame Side always, not to its Planets, but to the ſame fix’d Stars.

This Poſition of the Moons, in reſpect of their Planets, muſt occaſion a great many very ſurprizing Appearances to their Inhabitants, if they have any, which is very doubtful, but may for the preſent be ſuppos’d. An enquiry into our Moon may ſerve for all the reſt. Its Globe is divided into two Parts, in ſuch a manner, that thoſe who live on one Side never loſe the ſight of us, and thoſe on the other never enjoy it. Except only ſome few who live on the Confines of each of theſe, who loſe us, and ſee us again by turns. The Earth to them muſt ſeem The Aſtronomy of the Inhabitants of the Moon. much larger than the Moon doth to us, as being in Diameter above four times bigger. But that which is moſt ſurprizing, is, that Night and Day they ſee it always in the very ſame part of the Heaven, as if it never moved: ſome of them as if ’twas falling [136]upon their Heads: others ſomewhat above the Horizon, and others always in the Horizon, ſtill turning upon it ſelf, and preſenting them every twenty ſour Hours with a View of all its Countries, even of thoſe that lie near the Poles (I could wiſh my ſelf in the Moon only for the ſight of them) yet unknown and undiſcovered by us. They have it in its monthly Wane and Increaſe, they ſee it half, and horned, and full, by turns, juſt as we do the Body of the Moon. But the Light that they receive of us is five times larger than what we receive from them. So that in dark Nights that part that hath the Advantage of being towards us, receives a very glorious Light from us, tho’ Kepler thought otherwise. Their Days are always of the ſame Length with their Nights; and the Sun riſing and ſetting to them but once in one of our Months, makes the time both of their Light and Darkneſs to be equal to 15 of our Days. If their Bodies were of the ſame Materials with ours, thoſe that have the Sun pretty high in their Horizon, would be almoſt roaſted [137]in ſuch long Days. For the Sun is not farther from them than he is from us. This will be the Caſe of thoſe that live upon the Borders of the two Hemiſpheres we mentioned; but thoſe that live under the Poles of the Moon will be juſt about as hot as our Whale-fiſhers about Iſland and Nova Zemla are, in the Summer-time: who are in ſo little danger of being roaſted, that in the middle of their Summer, in their Days of three Months length, they very often find it extreme Cold. I call thoſe the Poles of the Moon, round which the fix’d Stars ſeem to turn to its Inhabitants, which are different from ours, and alſo from thoſe of the Ecliptick, although they move round theſe latter, at the diſtance of five Degrees, in a period of nineteen Years. Their Year they count by the Motion of the Stars, and their return to the Sun, and ’tis the ſame with ours. They can eaſily do it, becauſe they have the Stars Day and Night, notwithſtanding the Light of the Sun: for they have no Atmoſphere (which is the only reaſon that we don’t every [138]Day enjoy the ſame Sight) to hinder their Obſervations. Nor have they any Clouds to obſtruct their View, ſo that it is eaſier for them to find out the Courſes of the Planets, but more difficult to make a true Syſtem of them. For they will be apt to lay a wrong Foundation, by ſuppoſing that their Earth ſtands ſtill, which will lead them into more dangerous Errors than This may be applied to the Moons about Jupiter and Saturn. ever it did us. All that I have ſaid belongs as well to Jupiter’s and Saturn’s Satellites as to our Moon, in reſpect of the Planets they move round. The Length of their Day and Night is always equal to the Time of their Revolution: For example, the fifth Moon moves round Saturn in 80 Days, and the Days and Nights there are equal to Forty of ours. Both their Summer and Winter (Saturn moving round the Sun in thirty Years) are fifteen Years long. Therefore it is impoſſible but that their way of living muſt be very different from ours, having ſuch tedious Winters, and ſuch long watching and ſleeping times.

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Having thus explained the primary and ſecondary Planets round the Sun, we ſhould next ſet about the third Sort, the Sun and fix’d Stars; but before we do that, it would be worth while to ſet before you at once, in a clearer and more plain Method than hitherto, the Magnificence and Fabrick of the Solar Syſtem. Which we can’t poſſibly do in ſo ſmall a Space as one of our Leaves will but admit of, becauſe the Bodies of the Planets are ſo prodigiouſly ſmall in companion of their Orbs. But what is wanting in Figure ſhall be made up in Words. Going back then to the firſt Scheme, ſuppoſe another Fig. 1. like it, and proportionable, drawn upon a very large ſmooth Plain; whoſe outermoſt Circle repreſenting the Orb of Saturn, muſt be conceived three hundred and ſixty Foot in Semidiameter. In which you muſt place the Globe and Ring of Saturn of that Fig. 2. Bigneſs as the 2d Figure ſhows you. Let all the other Planets be ſuppoſed every one in his own Orbit, and in the middle of all the Sun, of the ſame Bigneſs that That Figure repreſents, [140]namely, about four Inches in Diameter. And then the Orbit or Circle in which the Earth moves, which the Aſtronomers call the Magnus Orbis, muſt have about ſix and thirty Foot in Semidiameter. In which the Earth muſt be conceived moving, not bigger than a grain of Millet, and her Companion the Moon ſcarcely perceivable, moving round her in a Circle a little more than two Inches Diameter, as in Fig. 5. the Figure here adjoined, where the Line A B repreſents a ſmall portion of that Circle which the Earth moves in: the ſmall Circle therein C is the Earth, and the Circle D E the Path of the Moon round it, in which the Body of the Moon is D.

The outermoſt of Saturn’s Moons moves in an Orbit whoſe Semidiameter is 29 Inches; that of Jupiter in a ſomewhat ſmaller, whoſe Semidiameter is 19 and a quarter.

And thus we have a true and exact Deſcription of the Sun’s Palace, where the Earth will be Twelve thouſand of its Semidiameters diſtant from him, which in German Miles makes above [141]ſeventeen Millions. But perhaps we may have a clearer Comprehenſion of this vaſt Length, by comparing it with ſome very ſwift Motion after the Example of Heſiod the Poet, who imagin’d that an Anvil let fall from the Top of Heaven, reach’d the Earth the tenth Day of its Journey, and in ten more arriv’d at the Bottom of Hell, the end of it: ſo making the Earth the mid-way between Heaven and Hell. I ſhan’t make uſe of the Anvil, but of ſomething as good, namely, a Bullet ſhot out of a great Gun, which may travel perhaps in a Moment, or Pulſe of an Artery, about a hundred Fathom, as is proved by thoſe Experiments that Merſennus in a Treatiſe of his relates; by which the Sound was found to extend itſelf eighty hundredth parts in the The immenſe diſtance between the Sun and Planets illuſtrated. ſame time. I ſay then, that ſuppoſing a Bullet to move with this Swiftneſs from the Earth to the Sun, it would ſpend 25 Years in its Paſſage. To make a Journey from Jupiter to the Sun, would require 125, and from Saturn thither 250 Years. This account depends upon the meaſure of the Earth’s [142]Diameter, which, according to the accurate Obſervations of the French, is 6538594 times ſix Paris Feet, one Degree being 57060 of that Meaſure. This ſhows us how vaſt thoſe Orbs muſt be, and how inconſiderable this Earth, the Theatre upon which all our mighty Deſigns, all our Navigations, and all our Wars are tranſacted, is when compared to them. A very fit Conſideration, and Matter of Reflection, for thoſe Kings and Princes who ſacrifice the Lives of ſo many People, only to flatter their Ambition in being Maſters of ſome pitiful Corner of this ſmall Spot. But to return to the matter in hand, now we have given you an account of the Sun’s proportion to thoſe Orbs and Bodies, we’ll ſee what more we can ſay of him.

No ground for Conjecture in the Sun. And ſome have thought it not improbable but that the Sun himſelf has alſo his Inhabitants. But upon what reaſon I cannot imagine, there being leſs ground for a Probability in him than in the Moon. For we are not yet ſure, whether he be a ſolid or liquid Globe; altho’, if my Notion of Light [143]be true, upon that account I ſhould rather think him liquid: which his Roundneſs and equal diſtribution of his Light to all parts are an Argument for. For that very ſmall inequality on his Surface, which is diſcovered by the Teleſcopes, (and that not always neither) which makes Men fancy they ſee boiling Seas and belching Mountains of Fire, is nothing but the trembling Motion of the Vapours our Atmoſphere is full of near the Earth; which is likewiſe The Faculæ in the Sun not eaſily ſeen. the Cauſe of the Stars twinkling. Nor could I ever have the Luck to diſcern thoſe bright Spots in the Sun which they boaſt as much of as they do of his dark ones, which latter I have very often ſeen; ſo that I have very good Reaſon to doubt whether there be any thing in the Sun brighter than the Sun itſelf. For by the moſt exact Obſervations, I could never find any ſuch pretended to be ſeen any where but juſt about his dark Spots; and it is no great wonder that thoſe Parts which are ſo near the darker, ſhould appear ſomewhat By reaſon of its Heat no Inhabitants like ours can live in the Sun. brighter than the reſt. That the Sun is extremely hot and fiery, is beyond [144]all diſpute, and ſuch Bodies as ours could not live one Moment in ſuch a Furnace. We muſt ſuppoſe a new ſort of Animals then, ſuch as we have no Idea or Likeneſs of among us, ſuch as we can neither imagine nor conceive: which is as much as to ſay, that we can make no Suppoſition at all about them. No doubt that glorious and vaſt Body was made for ſome noble End and Uſe, and fram’d with excellent Deſign. And I think we all very well know and feel its Uſefulneſs in that effuſion of Light and Heat to all the Planets round it; in the Preſervation and Happineſs of all living Creatures, and that not only in our Ball, but in thoſe vaſt Globes of Jupiter and Saturn, not contemptible when compared with its own. Theſe are ſuch great, ſuch wiſe Ends, that it is not ſtrange that the Sun ſhould have been made, if it had been only upon their account. For, as for Kepler’s Fancy, that he hath another Office, namely, to help on the Motion of the Planets in their own Orbs, by turning about his own Axis (which he would fain eſtabliſh in his Epitome of the Copernican [145]Syſtem) I ſhall give good Reaſons why I cannot aſſent to it.

The ſix’d Stars so many Suns. Before the Invention of Teleſcopes, it ſeemed to contradict Copernicus’s Opinion, to make the Sun one of the fix’d Stars. For the Stars of the firſt Magnitude being eſteem’d to be about three Minutes Diameter; and Copernicus (obſerving that tho’ the Earth changed its Place, they always kept the ſame diſtance from us) having ventur’d to ſay that the Magnus Orbis was but a Point in reſpect of the Sphere in which they were placed, it was a plain Conſequence that every one of them that appeared any thing bright, muſt be larger than the Path or Orbit of the Earth: which is very abſurd. This is the principal Argument that Tycho Brahe ſet up againſt Copernicus. But when the Teleſcopes took away thoſe Rays of the Stars which appear when we look upon them with our naked Eye, (which they do beſt when the Eye-glaſs is black’d with Smoke) they ſeemed juſt like little ſhining Points, and then that Difficulty vaniſhed, and the Stars may yet be ſo many Suns. Which is [146]the more probable, becauſe their Light is certainly their own: for it’s impoſſible that ever the Sun ſhould ſend, or they reflect it at ſuch a vaſt Diſtance. This is the Opinion that commonly goes along with Copernicus’s Syſtem. They are not all in the ſame Sphere. And the Patrons of it do alſo with reaſon ſuppoſe, that all theſe Stars are not in the ſame Sphere, as well becauſe there’s no Argument for it, as that the Sun, which is one of them, cannot be brought to this Rule. But it’s more likely they are ſcatter’d and diſpers’d all over the immenſe Spaces of the Heaven, and are as far diſtant perhaps from one another, as the neareſt of them are from the Sun.

Here again too I know Kepler is of another Opinion in his Epitome of Copernicus’s Syſtem, that we mention’d above. For tho’ he agrees with us, that the Stars are diffus’d through all the vaſt Expanſe of the Heavens, yet he cannot allow that they have as large an empty Space about them as our Sun has. For then ’twas his Opinion, we ſhould ſee but very few, and thoſe of very different Magnitudes: For, ſeeing [147]the largeſt of all appear ſo ſmall to us, that we can ſcarce obſerve or meaſure them with our beſt Inſtruments; how muſt thoſe appear that are three or four times farther from us? Why, ſuppoſing them no larger than theſe, they muſt ſeem three or four times leſs, and ſo on ’till a little farther they will not be to be ſeen at all: Thus we ſhall have the ſight of but very few Stars, and thoſe very different one from another; Whereas we have above a Thouſand, and thoſe not conſiderably bigger or leſs than one another. But this by no means proves what he would have it; and his Miſtake was chiefly, that he did not conſider the Nature of Fire and Flame which may be ſeen at ſuch diſtances, and at ſuch ſmall Angles as all other Bodies would totally diſappear under. A thing that we need go no farther than the Lamps ſet along the Streets to prove. For altho’ they are a hundred Foot from one another, yet you may count Twenty of them in a continued Row with your Eyes, and yet the twentieth Part of them ſcarce makes an Angle of ſix Seconds. Certainly [148]then the glorious Light of the Stars muſt do much more than this; ſo that it’s no wonder we ſhould ſee a Thouſand or two of them with our bare Eyes, and with a Teleſcope diſcover twenty times that number. But Kepler had a private Deſign in making the Sun thus ſuperiour to all the other Stars, and planting it in the Middle of the World, attended with the Planets: For his Aim was hereby to ſtrengthen his Coſmographical Myſtery, that the Diſtances of the Planets from the Sun are in a certain proportion to the Diameters of the Spheres that are inſcribed within, and circumſcribed about Euclid’s Regular Bodies. Which could never be ſo much as probable, except there were but one Chorus of Planets moving round the Sun, and ſo the Sun were the only one of his kind.

But that whole Myſtery is nothing but an idle Dream taken from Pythagoras or Plato’s Philoſophy. And the Author himſelf acknowledges that the Proportions do not agree ſo well as they ſhould, and is fain to invent two [149]or three very ſilly Excuſes for it. And he uſes yet poorer Arguments to prove that the Univerſe is of a ſpherical Figure, and that the Number of the Stars muſt neceſſarily be finite, becauſe the Magnitude of each of them is ſo. But what is worſt of all is, that he ſettles the Space between the Sun and the Concavity of the Sphere of the fix’d Stars, to be ſix hundred thouſand of the Earth’s Diameters. For this reaſon, which he has no Foundation for, that as the Diameter of the Sun is to that of the Orbit of Saturn, which he makes to be as 1 to 2000, ſo is this Diameter to that of the Sphere of the fixed Stars. I cannot but wonder how ſuch things as theſe could fall from ſo ingenious a Man, and ſo great an Aſtronomer. But I muſt be of the ſame Opinion with all the greateſt Philoſophers of our Age, that the Sun is of the ſame Nature with the fix’d Stars. And this will give us a greater Idea of the World, than all thoſe other Opinions. The Stars have Planets about them like our Sun. For then why may not every one of theſe Stars or Suns have as great a Retinue as our Sun, of Planets, with their [150]Moons, to wait upon them? Nay, there’s a manifeſt reaſon why they ſhould. For if we imagine our ſelves placed at an equal diſtance from the Sun and fix’d Stars; we ſhould then perceive no difference between them. For, as for all the Planets that we now ſee attend the Sun, we ſhould not have the leaſt glimpſe of them, either becauſe their Light would be too weak to affect us, or that all the Orbs in which they move would make up one lucid Point with the Sun. In this Station we ſhould have no occaſion to imagine any difference between the Stars, and ſhould make no doubt if we had but the Sight, and knew the Nature of one of them, to make that the Standard of all the reſt. We are then plac’d near one of them, namely, our Sun, and ſo near as to diſcover ſix other Globes moving round him, ſome of them having others performing them the ſame Office. Why then may not we make uſe of the ſame Judgment that we would in that caſe; and conclude, that our Star has no better attendance than the others? So that [151]what we allowed the Planets, upon the account of our enjoying it, we muſt likewiſe grant to all thoſe Planets that ſurround that prodigious number of Suns. They muſt have their Plants and Animals, nay and their rational Creatures too, and thoſe as great Admirers, and as diligent Obſervers of the Heavens as our ſelves; and muſt conſequently enjoy whatſoever is ſubſervient to, and requiſite for ſuch Knowledge.

What a wonderful and amazing Scheme have we here of the magnificent Vaſtneſs of the Univerſe! So many Suns, ſo many Earths, and every one of them ſtock’d with ſo many Herbs, Trees, and Animals, and adorn’d with ſo many Seas and Mountains! And how muſt our Wonder and Admiration be increaſed when we conſider the prodigious Diſtance and Multitude of the Stars?

That their Diſtance is ſo immenſe, that the Space between the Earth and Sun (which is no leſs than Twelve thouſand of the Earth’s Diameters) is almoſt nothing when compar’d to it, has more Proofs than one to confirm [152]it. And this among the reſt. If you obſerve two Stars near one another, as for example thoſe in the middle of the Great Bears Tail, differing very much from one another in Clearneſs, notwithſtanding our changing our Poſition in our Annual Orbit round the Sun, and that there would be a Parallax were the Star which is brighter nearer to us than the other, as is very probable it is, yet whatever Part of the Year you look upon them, they will not in the leaſt have altered their diſtance. Thoſe that have hitherto undertook to calculate their Diſtance, have not been able perfectly to compaſs their Deſign, by reaſon of the extreme Niceneſs and almoſt Impoſſibility of the Obſervations requiſite for their Purpoſe. The only Method that I ſee remaining, to come at any tolerable Probability in ſo difficult a Caſe, I ſhall here make uſe of. Seeing then that the Stars, as I ſaid before, are ſo many Suns, if we do but ſuppoſe one of them equal to ours, it will follow that its diſtance from us is as much greater than that of the Sun, as its apparent [153]Diameter is leſs than the Diameter of the Sun. But the Stars, even thoſe of the firſt Magnitude, though view’d through a Teleſcope, are ſo very ſmall, that they ſeem only like ſo many ſhining Points, without any perceivable Breadth. So that ſuch Obſervations can here do us no good. When A way of making a probable gueſs at the diſtance of the Stars. I ſaw this would not ſucceed, I ſtudied by what way I could ſo leſſen the Diameter of the Sun, as to make it not appear larger than the Dog, or any other of the chief Stars. To this purpoſe I clos’d one End of my twelve-foot Tube with a very thin Plate, in the Middle of which I made a Hole not exceeding the twelfth Part of a Line, that is the hundred and forty fourth Part of an Inch. That End I turn’d to the Sun, placing my Eye at the other, and I could ſee ſo much of the Sun as was in Diameter about the 182d part of the Whole. But ſtill that little piece of him was brighter much than the Dog-ſtar is in the cleareſt Night. I ſaw that this would not do, but that muſt leſſen the Diameter of the Sun a great deal more. I made [154]then ſuch another Hole in a Plate, and againſt it I plac’d a little round Glaſs that I had made uſe of in my Microſcopes, of much about the ſame Diameter with the former Hole. Then looking again towards the Sun (taking care that no Light might come near my Eye to hinder my Obſervation) I found it appeared of much the ſame Clearneſs with Sirius. But caſting up my account, according to the Rules of Dioptricks, I found his Diameter now was but 1⁄152 part of that hundred and eighty ſecond part of his whole Diameter that I ſaw through the former Hole. Multiplying 1⁄152 and 1⁄182 into one another, the Product I found to be 1⁄27664​. The Sun therefore being contracted into ſuch a Compaſs, or being removed ſo far from us (for it’s the ſame thing) as to make his Diameter but the 27664 part of that we every Day ſee, will ſend us juſt the ſame Light as the Dog-ſtar now doth. And his diſtance then from us will be to his preſent diſtance undoubtedly as 27664 is to 1; and his Diameter little above four Thirds, 4‴. Seeing [155]then Sirius is ſuppoſed equal to the Sun, it follows that his Diameter is likewiſe 4‴, and that his Diſtance to the Diſtance of the Sun from us is as 27664 to 1. And what an incredible Diſtance that is, will appear by the ſame way of reaſoning that we uſed in meaſuring that of the Sun. For if 25 Years are required for a Bullet out of a Cannon, with its utmoſt Swiftneſs, to travel from the Sun to us; then by multiplying the Number 27664 into 25, we ſhall find that ſuch a Bullet would ſpend almoſt ſeven hundred thouſand Years in its Journey between us and the neareſt of the fix’d Stars. And yet when in a clear Night we look upon them, we cannot think them above ſome few Miles over our Heads. What I have here enquir’d into, is concerning the neareſt of them. And what a prodigious Number muſt there be beſides of thoſe which are placed in the vaſt Spaces of Heaven, as to be as remote from theſe as theſe are from the Sun! For if with our bare Eyes we can obſerve above a Thouſand, and with a Teleſcope can [156]diſcover ten or twenty times as many; what bounds of Number can we ſet to thoſe which are out of the Reach even of theſe Aſſiſtances! eſpecially if we conſider the infinite Power of God. Really, when I have been reflecting thus with my ſelf, me-thoughts all our Arithmetick was nothing, and we are vers’d but in the very Rudiments of Numbers, in compariſon of this great Sum. For this requires an immenſe Treaſury, not of twenty or thirty Figures only, in our decuple Progreſſion, but of as many as there are Grains of Sand upon the Shore. And yet who can ſay, that even this Number exceeds that of the Fix’d Stars? Some of the Ancients, and Jordanus Brunus carry’d it further, in declaring the Number infinite: he would perſwade us that he has prov’d it by many Arguments, tho’ in my opinion they are none of them concluſive. Not that I think the contrary can ever be made out. Indeed it ſeems to me certain, that the Univerſe is infinitely extended; but what God has been pleas’d to place beyond the Region of [157]the Stars, is as much above our Knowledge, as it is beyond our Habitation.

Or what if beyond ſuch a determinate Space he has left an infinite Vacuum; to ſhow, how inconſiderable all that he has made is, to what his Power could, had he ſo pleas’d, have produced? But I am falling, before I am aware, into that intricate Diſpute of Infinity: Therefore I ſhall wave this, and not, as ſoon as I am free of one, take upon me another difficult Task. All that I ſhall do more is to add ſomewhat of my Opinion concerning the whole World, as it is a Place for the Reception of the Suns or fix’d Stars, every one of which, I have ſhowed, may have their Planetary Syſtems about them.

Every Sun has a Vortex round it, very different from thoſe of Cartes. I am of Opinion then that every Sun is ſurrounded with a Whirl-pool or Vortex of Matter in a very ſwift Motion; tho’ not in the leaſt like Cartes’s either in their Bulk, or manner of Motion. For Cartes makes his ſo large, as every one of them to touch all the others round them, in a flat Surface, juſt as you have ſeen the Bladders that [158]Boys blow up in Soap-ſuds do; and would have the whole Vortex to move round the ſame way. But the Angles of every Vortex will be no ſmall hindrance to ſuch a Motion. Then the whole Matter moving round at once, upon the Axis as it were of a Cylinder, did not a little puzzle him in giving Reaſons for the Roundneſs of the Sun: which however they may ſatisfy ſome People that do not conſider them, really prove nothing of the Matter. In this æthereal Matter the Planets float, and are carried round by its Motion: and the thing that keeps them in their own Orbs is, that they themſelves, and the Matter in which they ſwim, equally ſtrive to fly off from the Center of this Motion. Againſt all which there are many Aſtronomical Objections, ſome of which I touch’d upon in my Eſſay of the Cauſes of Gravity. Where I gave another Account of the Planets not deſerting their own Orbs; which is their Gravitation towards the Sun. I ſhow’d there the Cauſes of that Gravitation, and cannot but wonder that [159]Cartes, the firſt Man that ever began to talk reaſonably of that Matter, ſhould never meddle with, or light on it. Plutarch in his Book of the Moon above-mentioned ſays, that ſome of the Ancients were of Opinion, that the Reaſon of the Moon’s keeping her Orbit was, that the Force of her Circular Motion was exactly equal to her Gravity, the one of which pull’d her to, as much as the other forc’d off from the Centre. And in our Age Alphonſus Borellus, who was of this ſame Opinion in the other Planets as well as the Moon, makes the Gravitation of the primary Planets to be towards the Sun, as that of the Secondary is towards the Planets round which they move: Which Sir Iſaac Newton has more fully explain’d, with a great deal of Pains and Subtilty; and how from that Cauſe proceeds the Ellipticity of the Orbs of the Planets, found out by Kepler. According to my Notion of the Gravitation of the Planets to the Sun, the Matter of his Vortex muſt not at all move the ſame [160]way, but after ſuch a manner as to have its Parts carry’d different ways on all Sides. And yet there is no fear of its being deſtroyed by ſuch an irregular Motion, becauſe the Æther round it, which is at reſt, keeps the Parts of it from flying out. With the Help of ſuch a Vortex as this I have undertook in that Eſſay to explain the Gravity of Bodies on this Earth, and all the Effects of it. And I ſuppoſe there may be the ſame Cauſe as well of the Gravitation of the Planets, and of our Earth among the reſt, towards the Sun, as of their Roundneſs: A Thing ſo very hard to give an Account of in Cartes’s Syſtem.

I muſt differ from him too in the Bigneſs of the Vortices, for I cannot allow them to be ſo large as he would make them. I would have them diſperſed all about the immenſe Space, like ſo many little Whirl-pools of Water, that one makes by the ſtirring of a Stick in any large Pond or River, a great way diſtant from one another. And as their Motions do not all intermix [161]or communicate with one another, ſo in my Opinion muſt the Vortices of Stars be placed as not to hinder one anothers free Circumrotations.

So that we may be ſecure, and never fear that they will ſwallow up or deſtroy one another; for that was a mere Fancy of Cartes’s, when he was a ſhowing how a fix’d Star or Sun might be turn’d into a Planet. And ’tis plain that when he writ it, he had no Thoughts of the immenſe Diſtance of the Stars from one another; particularly, by this one Thing, that he would have a Comet as ſoon as ever it comes into our Vortex, to be ſeen by us. Which is as abſurd as can be. For how could a Star, which gives us ſuch a vaſt Light only from the Reflection of the Beams of the Sun, as he himſelf owns they do; how I ſay could that be ſo plainly ſeen at a diſtance Ten thouſand times larger than the Diameter of the Earth’s Orbit? He could not but know that all round the Sun there is a vaſt Extenſum; ſo vaſt, that in Copernicus’s Syſtem the [162]magnus Orbis is counted but a Point in compariſon with it. But indeed all the whole Story of Comets and Planets, and the Production of the World, is founded upon ſuch poor and trifling Grounds, that I have often wonder’d how an ingenious Man could ſpend all that pains in making ſuch Fancies hang together. For my part, I ſhall be very well contented, and ſhall count I have done a great Matter, if I can but come to any Knowledge of the Nature of Things, as they now are, never troubling my ſelf about their Beginning, or how they were made, knowing that to be out of the reach of human Knowledge, or even Conjecture.

FINIS.