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The more common and general opinion is, that the spots are the thinner parts of the moon, which are less able to reflect the beams that they receive from the sun, and this is most agreeable to reason; for if the stars are therefore brightest, because they are thicker and more solid than their orbs, then it will follow, that those parts of the moon which have less light, have also less thickness *. It was the providence of nature (say some) that so contrived that planet to have these spots within it; for since that is nearest to those lower bodies which are so full of deformity, it is requisite that it should in some measure agree with them; and as in this inferior world, the higher bodies are the most complete, so also in the heavens, perfection is ascended unto by degrees, and the moon being the lowest, must be the least pure; and therefore Philo the Jew interpreting Jacob's dream concerning the ladder †, doth in an allegory shew how that in the fabric of the world, all things grow perfecter as they grow higher; and this is the reason (saith he) why the moon doth not consist of any pure simple matter, but is mixed with air, which shews so darkly within her body.

But this cannot be a sufficient reason; for though it were true that nature did frame every thing perfecter as it was higher, yet is it as true that nature frames every thing fully perfect for that office to which she intends it. Now had she intended the moon merely to reflect the sunbeams, and give light, the spots then had not so much argued her providence, as her unskilfulness and oversight, as if in the haste of her work she could not tell how to make that body exactly fit for that office to which she intended it 1.

It is likely then that she had some other end which moved her to produce this variety; and this, in all probability, was her intent, to make it a fit body for habitation, with the same conveniences of sea and land, as this inferior world doth partake of. For since the moon is such a

* Albert. mag. de Coævis. Q. 4. Art. 21. Colleg. Con.

+ De somniis.

Scalig. exercit. 62.

vast, such a solid and opacous body, like our earth (as was above proved) why may it not be probable that those thinner and thicker parts appearing in her, do shew the difference betwixt the sea and land in that other world? And Galilæus doubts not, but that if our earth were visible at the same distance, there would be the like appearance of it.

If we consider the moon as another habitable earth, then the appearances of it will be altogether exact and beautiful, and may argue unto us that it is fully accomplished for all those ends to which Providence did appoint it. But consider it barely as a star or light, and then there will appear in it much imperfection and deformity, as being of an impure dark substance, and so unfit for the office of that

nature.

As for the form of those spots, some of the vulgar think they represent a man, and the poets guess it is the boy Endymion, whose company she loves so well, that she carries him with her: others will have it only to be the face of a man, as the moon is usually pictured; but Albertus thinks rather, that it represents a lion with his tail towards the east, and his head the west; and some others have thought it to be very much like a fox; and certainly it is as much like a lion as that in the zodiac, or as ursa major is like a bear.

*

I should guess that it represents one of these as well as another, and any thing else as well as any of these, since it is but a strong imagination which fancies such images, as school-boys usually do in the marks of a wall, whereas there is not any similitude in the spots themselves, which rather like our sea, in respect of the land, appears under a rugged and confused figure, and doth not represent any distinct image: so that both in respect of the matter and the form, it may be probable enough that those spots and brighter parts may shew the distinction betwixt the sea and land in that other world.

*Eusebius Nieremb. Hist. Nat. 1. 8. c. 15.

PROP. VIII.

The spots represent the sea, and the brighter parts the

land.

W water with those appearances in the moon, I con

THEN I first compared the nature of our earth and

cluded contrary to the proposition, that the brighter parts represented the water, and the spots the land. Of this opinion likewise was Keplar at the first *. But my second thoughts, and the reading of others, have now convinced me (as after he was) of the truth of that proposition which I have now set down. Before I come to the confirmation of it, I shall mention those scruples which at first made me doubt the truth of this opinion.

1. It may be objected, it is probable, if there be any such sea and land as ours, that it bears some proportion and similitude with ours: but now this proposition takes away all likeness betwixt them. For whereas the superficies of our earth is but the third part of the whole surface in the globe, two parts being overspread with the water (as Scaliger observes +), yet here, according to this opinion, the sea should be less than the land, since there is not so much of the bespotted as there is of the enlightened parts; wherefore it is probable that there is no such thing at all, or else that the brighter parts are the sea.

2. The water, by reason of the smoothness of its superficies, seems better able to reflect the sun-beams than the earth, which in most places is so full of ruggedness, of grass and trees, and such like impediments of reflection; and besides, common experience shews that the water shines with a greater and more glorious brightness than the earth; therefore it should seem that the spots are the earth, and

*Opt. Astro. c. 6. num. 9. Dissert. cum nuncio Gal.
+ Exercit. 38.

the brighter parts the water. But to the first it may be answered.

1. There is no great probability in this consequence, that because it is so with us, therefore it must be so with the parts of the moon; for since there is such a difference betwixt them in divers other respects, they may not perhaps agree in this.

2. That assertion of Scaliger is not by all granted for a truth. Fromondus with others think that the superficies of the sea and land, in so much of the world as is already discovered, is equal and of the same extension.

3. The orb of thick and vaporous air which encompasses the moon, makes the brighter parts of that planet appear bigger than in themselves they are; as I shall shew afterwards.

To the second it may be answered, That though the water be of a smooth superficies, and so may seem most fit to reverberate the light, yet because it is of a perspicuous nature, therefore the beams must sink into it, and cannot so strongly and clearly be reflected. Sicut in speculo ubi plumbum abrasum fuerit (saith Cardan), as in lookingglasses, where part of the lead is razed off, and nothing left behind to reverberate the image, the species must there pass through, and not back again: so it is where the beams penetrate and sink into the substance of the body, there cannot be such an immediate and strong reflection, as when they are beat back from the superficies; and therefore the sun causes a greater heat by far upon the land, than upon the water. Now as for that experiment, where it is said, that the waters have a greater brightness than the land; I answer, It is true only there where they represent the image of the sun, or some bright cloud, and not in other places; especially if we look upon them at any great distance, as is very plain by common observation.

And it is certain, that from any high mountain the land does appear a great deal brighter than any lake or river.

* De Meteoris, 1. 5. e. 1. Art. 1.

This may yet be farther illustrated by the similitude of a looking-glass hanging upon a wall in the sun-shine; where, if the eye be not placed in the just line of reflection from the glass, it is manifest that the wall will be of a brighter appearance than the glass. True indeed, in the line of reflection, the light of the glass is equal almost unto that which comes immediately from the sun itself; but now this is only in one particular place, and so is not like that brightness which we discern in the moon; because this does appear equally in several situations, like that of the wall, which does seem bright as well from every place, as from any one. And therefore the roughness of the wall, or (as it is in the objection) the ruggedness of our earth, is so far from being an hindrance of such a reflection as there is from the moon, that it is rather required as a necessary condition unto it. We may conceive that in every rough body, there are, as it were, innumerable superficies, disposed unto an innumerable diversity of inclinations. Ita ut nullus sit locus, ad quem non pertingant plurimi radii reflexi a plurimis superficieculis, per omnem corporis scabri radiis luminosis percussi superficiem dispersis*. So that "there is not any place unto which there are not some "beams reflected from these diverse superficies, in the "several parts of such a rugged body." But yet (as I said before) the earth does receive a great part of its light. by illumination, as well as by reflection.

So that notwithstanding those doubts, yet this proposition may remain true, That the spots may be the sea, and the brighter parts the land. Of this opinion was Plutarch+: unto him assented Keplar and Galilæus, whose words are these: Si quis veterum Pythagorcorum sententiam exsuscitare velit, lunam scilicet esse quasi tellurem alteram ejus pars lucidior terrenam superficiem, obscurior vero aqueam magis congruè repræsentet. Mihi autem dubium fuit nunquam terrestris globi à longe conspecti, atque a radiis sola

*Galilæus System. Coll. 1.

+ De facie Lun. Dissertatio Nunc. Şyd.

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