Chapter III: Part 3

We have ſpoke of theſe Arts and Inventions, which it is very probable the Inhabitants of the Planets partake of in common with us, beſides which it ſeems requiſite to take in many other Things that ſerve either for the Uſe or Pleaſure of their Lives. But what theſe Things are we ſhall the better account for, by laying before us many of thoſe Things which are found among us. I have before mention’d the Variety of Animals and Vegetables, which very much differ from each other, among which there are ſome that differ but little; and I have ſaid, that there are no leſs differences in theſe Things in the Planetary Worlds.

I ſhall now take a ſhort view of the Benefits we receive both from thoſe Herbs and Animals, and ſee whether we may not with very good reaſon conclude that the Planetary Inhabitants reap as great and as many from thoſe that their Countries afford them.

And here it may be worth our while to take a Review of the Variety and Multitude of our Riches. For Trees and Herbs do not only ſerve us for Food, they in their delicious Fruits, theſe in their Seeds, Leaves and Roots; but Herbs moreover furniſh us with Phyſick, and Trees with Timber for our Houſes and Ships. Flax, by the means of thoſe two uſeful Arts of Spinning and Weaving, affords us Clothing. Of Hemp or Matweed we twiſt our ſelves Thread and ſmall Ropes, the former of which we employ in Sails and Nets, the latter in making larger Ropes for Maſts and Anchors. With the ſweet Smells and [The Advantages we reap from Herbs and Animals.] beauteous Colours of Flowers we feaſt our Senſes: and even thoſe of them, that offend our Noſtrils, or are miſchievous to our Bodies, are ſeldom without excellent Uſes: or were made perhaps by Nature as a Foil to ſet off, and make us the more value the Good by comparing them with theſe. What vaſt Advantages and Profit do we reap from the Animals? The Sheep give us Clothing, and the Cows afford us Milk: and both of them their Fleſh for our Suſtenance. Aſſes, Camels, and Horſes do, what if we wanted them we muſt do our ſelves, carry our Burdens; and the laſt of them we make uſe of, either themſelves to carry us, or in our Coaches to draw us. In which we have ſo excellent, ſo uſeful an Invention of Wheels, that I can’t ſuppoſe the Planets to enjoy Society and all its Conſequences, and be without them. Whether they are Pythagoreans there, or feed upon Fleſh as we do, I dare not affirm any Thing. Tho’ it ſeems to be allowed Men to feed upon whatſoever may afford them Nouriſhment, either on Land, or in Water, upon Herbs, and Pomes, Milk, Eggs, Honey, Fiſh, and no leſs upon the Fleſh of many Birds and Beaſts. But it is a ſurpriſing thing! that a rational Creature ſhould live upon the Ruin and Deſtruction of ſuch a number of other his Fellow-Creatures! And yet it does not ſeem at all unnatural, ſince not only he, but even Lions, Wolves, and other ravenous Beaſts, prey upon Flocks of other harmleſs Things, and make mere Fodder of them; as Eagles do of Pidgeons and Hares; and large Fiſh of the helpleſs little ones. We have different ſorts of Dogs for Hunting, and what our own Legs cannot, that their Noſe and Legs can help us to. But the Uſe and Profit of Herbs and Animals are not the only Things they are good for, but they raiſe our Delight and Admiration when we conſider their various Forms and Natures, and enquire into all their different ways of Generation: Things ſo infinitely multifarious, and ſo delightfully amazing, that the Books of natural Philoſophers are deſervedly filled with their Encomiums. For even in the very Inſects, who can but admire the ſix-corner’d Cells of the Bees, or the artificial Web of a Spider, or the fine Bag of a Silk-worm, which laſt affords us, with the Help of incredible Induſtry, even Shiploads of ſoft delicate Clothing. This is a ſhort Summary of thoſe many profitable Advantages the animal and herbal World ſerve us with.

But this is not all. The Bowels of the Earth likewiſe contribute much to Man’s Happineſs. For what Art and Cunning does he employ in finding, in digging, in trying Metals, and in melting, refining, and tempering them? [And from Metals.] What Skill and Nicety in beating, drawing or diſſolving Gold, ſo as with inconſiderable Changes to make every Thing he pleaſes put on that noble Luſtre? Of how many and admirable Uſes is Iron? and how ignorant in all Mechanical Knowledge were thoſe Nations that were not acquainted with it, ſo as to have no other Arms but Bows, Clubs, and Spears, made of Wood. There’s one Thing indeed we have, which it’s a Queſtion whether it has done more harm or good, and that is Gun-powder made of Nitre and Brimſtone. At firſt indeed it ſeem’d as if we had got a more ſecure Defenſe than former Ages againſt all Aſſaults, and could eaſily guard our Towns, by the wonderful Strength of that Invention, againſt all hoſtile Invaſions: but now we find it has rather encouraged them, and at the ſame time been no ſmall Occaſion of the Decay of Valour, by rendring it and Strength almoſt uſeleſs in War. Had the Grecian Emperor who ſaid, Virtue was ruin’d only when Slings and Rams firſt came into uſe, liv’d in our Days, he might well have complain’d; eſpecially of Bombs, againſt which neither Art nor Nature is of ſufficient Proof: but which lays every Thing, Caſtles and Towers, be they never ſo ſtrong, even with the Ground. If for nothing elſe, yet upon this one account, I think we had better have been without the Diſcovery. Yet, when we were talking of our Diſcoveries, it was not to be paſs’d over, for the Planets too may have their miſchievous as well as uſeful Inventions.

We are happier in the Uſes for which the Air and Water ſerves us; both of which helps us in our Navigation, and furniſhes us with a Strength ſufficient, without any Labour of our own, to turn round our Mills and Engines; Things which are of uſe to us in ſo many different Employments. For with them we grind our Corn, and ſqueeze out our Oil; with them we cut Wood, and mill Cloth, and with them we beat our Stuff for Paper. An incomparable Invention! Where the naſtieſt uſeleſs Scraps of Linen are made to produce fine white Sheets. To theſe we may add the late diſcovery of Printing, which not only preſerves from Death Arts and Knowledge, but makes them much eaſier to be attained than before. Nor muſt we forget the Arts of Engraving and Painting, which from mean Beginnings have improved to that Excellence, that nothing that ever ſprung from the Wit of Man can claim Pre-eminence to them. Nor is the way of melting and blowing Glaſſes, and of poliſhing and ſpreading Quick-ſilver over Looking-Glaſſes, unworthy of being mentioned, nor above all, the admirable uſes that Glaſſes have been put to in natural Knowledge, ſince the Invention of the Teleſcope and Microſcope. And no leſs nice and fine is the Art of making Clocks, ſome of which are ſo ſmall as to be no weight to the Bearer; and others ſo exact as to meaſure out the Time in as ſmall Portions as any one can deſire: the Improvement of both which the World owes to my [1]Inventions.

[From the diſcoveries of our Age.]

I might add much here of the late Diſcoveries, moſt of them of this Age, which have been made in all ſorts of Natural Knowledge as well as in Geometry and Aſtronomy, as of the Weight and Spring of the Air, of the Chymical Experiments that have ſhown us a way of making Liquors that ſhall ſhine in the Dark, and with gentle moving ſhall burn of themſelves. I might mention the Circulation of the Blood through the Veins and Arteries, which was underſtood indeed before; but now, by the help of the Microſcope, has an ocular demonſtration in the Tails of ſome Fiſhes: of the Generation of Animals, which now is found to be performed no otherwiſe than by the Seed of one of the ſame kind; and that in the Seed of the Male are diſcover’d, by the help of Glaſſes, Millions of ſprightly little Animals, which it’s probable are the very Offspring of the Animals themſelves: a ſurpriſing thing, and never before now known!

[The Planets have, tho’ not theſe ſame, yet as uſeful Inventions.]

Thus have I put together all theſe late Diſcoveries of our Earth: and now, tho’ perhaps ſome of them may be common to the Planetary Inhabitants with us, yet that they ſhould have all of them is not credible. But then they may have ſomewhat to make up that Defect, others as good and as uſeful, and as wonderful, that we want. We have allow’d that they may have rational Creatures among them, and Geometricians, and Muſicians: We have prov’d that they live in Societies, have Hands and Feet, are guarded with Houſes and Walls: Wherefore if a Man could be carried thither by ſome powerful Genius, ſome Mercury, I don’t doubt ’twould be a very curious ſight, curious beyond all Imagination, to ſee the odd ways, and the unuſual manner of their ſetting about any thing, and their ſtrange methods of living. But ſince there’s no hopes of our going ſuch a Journey, we muſt be contented with what’s in our Power: we may ſuppoſe our ſelves there, and inquire as far as we can into the Aſtronomy of each Planet, and ſee in what manner the Heavens preſent themſelves to their Inhabitants. We ſhall make ſome Obſervations of the Eminence of each of them, in reſpect of their Magnitude, and number of Moons they have to wait on them; and ſhall propoſe a new Method of coming to ſome Knowledge of the incredible diſtance of the ſix’d Stars. But firſt after this long and deep Thoughtfulneſs we will give our ſelves a little Reſt, and ſo put an end to this Book.

New Conjectures concerning the
Planetary Worlds.

BOOK the Second.

’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 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 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 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, 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 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 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 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 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. 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 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 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 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 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 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, 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; 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, 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 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 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 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.

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 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 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.

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 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 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.

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 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 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 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 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 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 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 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.