In answering to these objections, I shall first shew, that this light cannot be her owne, and then declare that which is the true reason of it.

That it is not her owne, appeares.

1 Because then she would alwayes retaine it, but shee has beene sometimes altogether invisible, when as notwithwanding some of the fixed Starres of the fourth or fifth magnitude might easily have been discerned close by her,⁶ As it was in the yeare 1620.

2 This may appeare likewise from the variety of it at divers times; for ‘tis commonly observed that sometimes ‘tis of a brighter, sometimes of a darker appearance, now redder, and at another time of a more duskish colour. The observation of this variety in divers eclipses, you may see set downe by Keplar and many others.⁷ But now this could not be, if that light were her owne, that being constantly the same, and without any reason of such an alteration: So that thus I may argue.

If there were any light proper to the Moone, then would that Planet appeare brightest when she is eclipsed in her Perige being neerest to the earth, and so consequently more obscure and duskish when shee is in her Apoge or farthest from it; the reason is, because the neerer any enlightned body comes to the sight, by so much the more strong are the species and the better perceived. This sequell is granted by some of our adversaries,⁸ and they are the very words of noble Tycho, Si Luna genuino gauderet lumine, utique cum in umbra terrae esset, illud non amitteret, sed eò evidentiùs exereret; omne enim lumen in tenebris, plus splendet cum alio majore fulgore non praepeditur. If the Moone had any light of her own, then would she not lose it in the earths shadow, but rather shine more clearely; since every light appeares greater in the dark, when it is not hindered by a more perspicuous brightnesse.

But now the event falls out cleane contrary,⁹ (as observation doth manifest, and our opposites themselves doe grant) the Moone appearing with a more reddish and cleare light when she is eclipsed, being in her Apoge or farthest distance, and a more blackish iron colour when shee is in her Perige or nearest to us, therefore she hath not any light of her owne. Nor may wee think that the earths shadow can cloud the proper light of the Moone from appearing, or take away any thing from her inherent brightnesse; for this were to think a shadow to be a body, an opinion altogether misbecomming a Philosopher, as Tycho grants in the fore-cited place, Nec umbra terrae corporeum quid est, aut densa aliqua substantia, ut Lunae lumen obtenebrare possit, atque id visui nostro praeripere, sed est quaedam privatio luminis solaris, ob interpositum opacum corpus terrae. Nor is the earths shadow any corporall thing, or thick substance, that it can cloud the Moones brightnesse, or take it away from our sight; but it is a meere privation of the Sunnes light by reason of the interposition of the earths opacous body.

3 If she had any light of her owne, then that would in it selfe be either such a ruddy brightnesse as appeares in the eclipses, or else such a leaden duskish light as wee see in the darker parts of her body, when shee is a little past the conjunction. (That it must be one of these may follow from the opposite arguments) but it is neither of these, therefore shee hath none of her owne.

1 ‘Tis not such a ruddy light as appeares in eclipses; for then why can we not see the like rednesse, when wee may discerne the obscurer parts of the Moone?

You will say, perhaps, that then the neerenesse of that greater light takes away that appearance.

I reply, this cannot be; for then why does Mars shine with his wonted rednesse, when hee is neere the Moone? or why cannot her greater brightnesse make him appeare white as the other Planets? nor can there be any reason given why that greater light should represent her body under a false colour.

2. ‘Tis not such a duskish leaden light, as we see in the darker part of her body, when shee is about a sextile Aspect distant from the Sunne; for then why does shee appeare red in the eclipses, since meere shade cannot cause such variety? for ‘tis the nature of darknesse by its opposition, rather to make things appeare of a more white and cleare brightnesse than they are in themselves. Or if it be the shade, yet those parts of the Moone are then in the shade of her body, and therefore in reason should have the like rednesse. Since then neither of these lights are hers, it followes that she hath none of her owne. Nor is this a singular opinion, but it hath had many learned Patrons;¹⁰ such was Macrobius, who being for this quoted of Rhodiginus, hee calls him vir reconditissimae scientiae,¹¹ a man who knew more than ordinary Philosophers, thus commending the opinion in the credit of the Author. To him assents the venerable Bede, upon whom the glosse hath this comparison.¹² As the Looking-glasse represents not any image within it selfe unlesse it receive some from without; so the Moone hath not any light, but what is bestowed by the Sunne. To these agreed¹³ Albertus Magnus,¹⁴ Scaliger,¹⁵ Maeslin, Keplar, and more especially¹⁶ Mulapertius, whose words are more pat to the purpose than others, and therefore I shall set them down as you may finde them in his Preface to his Treatise concerning the Austriaca sydera; Luna, Venus, & Mercurius, terrestris & humidae sunt substantiae, ideoque de suo non lucere, sicut nec terra. The Moone, Venus, and Mercury (saith he) are of an earthly and moyst substance, and therefore have no more light of their owne, then the earth hath. Nay, some there are, who think, (though without ground) that all the other Starres doe receive that light, whereby they appeare visible to us, from the Sunne: so Ptolomie,¹⁷ Isidore Hispalensis,¹⁸ Albertus Magnus, and¹⁹ Bede; much more then must the Moone shine with a borrowed light.

But enough of this. I have now sufficiently shewed what at the first I promised,²⁰ that this light is not proper to the Moone.²¹ It remaines in the next place, that I tell you the true reason of it.²² And here, I think ‘tis probable that the light which appeares in the Moone at the eclipses, is nothing else but the second species of the Sunnes rayes which passe through the shadow unto her body: and from a mixture of this second light with the shadow, arises that rednesse which at such times appeares unto us. I may call it Lumen crepusculinum, the Aurora of the Moon, or such a kinde of blushing light, that the Sunne causes when he is neere his rising, when he bestowes some small light upon the thicker vapours. Thus we see commonly the Sunne being in the Horizon, and the reflexion growing weak, how his beames make the waters appeare very red.

The Moabites in Iehorams time, (2 King. 3. 22) when they rose early in the morning, and beheld the waters afarre off, mistooke them for blood. Et causa hujus est quia radius solaris in Aurora contrahit quandam rubedinem,²³ propter vapores combustos manentes circa superficiem terrae, per quos radij transeunt, & ideo cum repercutiantur in aqua ad oculos nostros, trahunt secum eundem ruborem, & faciunt apparere locum aquarum, in quo est repercussio, esse rubrum, saith Tostatus. The reason is, because of his rayes, which being in the lower vapours, those doe convay an imperfect mixed light upon the waters. Thus the Moone being in the earths shadow, and the Sunne beames which are round about it, not being able to come directly unto her body, yet some second rayes there are, which passing through the shadow, make her appeare in that ruddy colour: So that shee must appeare brightest when shee is eclipsed, being in her Apoge or greatest distance from us, because then the cone of the earths shadow is lesse, and the refraction is made through a narrower medium. So on the contrary, shee must be represented under a more dark and obscure forme when she is eclipsed, being in her Perige or neerest to the earth, because then shee is involved in a greater shadow, or bigger part of the cone, and so the refraction passing through a greater medium, the light must needs be weaker which doth proceed from it. If you ask now, what the reason may be of that light which wee discerne in the darker part of the new Moone? I answer, ‘tis reflected from our earth, which returnes as great a brightnesse to that Planet, as it receives from it. This I shall have occasion to prove afterward.

I have now done with these propositions which were set downe to cleare the passage, and confirme the suppositions implied in the opinion;²⁴ I shall in the next place proceed to a more direct treating of the chiefe matter in hand.

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Footnotes

1. Tostatus in 1 Gen. ↩

2. Hyeron. de Sancta fide. Hebraeomast. l. 2. c. 4 ↩

3. Lib. 9. Architecturae. ↩

4. Narratio Psalmorum. item. ep. 119. ↩

5. De Subtil. lib. 3. ↩

6. Keplar. epit. Astron. cop. l. 6. p. 5. sect. 2. ↩

7. Opt. Astron. c. 7. num. 3. ↩

8. De nova stella. lib. 1. c. 10. ↩

9. Reinhold Comment. in Purb. Theor pag. 164. ↩

10. Somn. Scip. l. 1. c. 20. ↩

11. Lect. antiq. l. 1. c. 15. ↩

12. In lib. de natur. rerum. ↩

13. De 4. Coaevis. Q. 4 Art. 21. ↩

14. Exercit. 62. ↩

15. Epitom. Astron. l. 4. p. 2. ↩

16. Epit. Astro. Cop. l. 6 part. 5. sect. 2. ↩

17. Originum l. 3. c. 60. ↩

18. De Coelo. l. 2. ↩

19. De ratione tempor. c. 4. ↩

20. Item Plinie lib. 2. ca. 6. ↩

21. Hugo de Sancto Victore. ↩

22. Annot. in Gen. 6. ↩

23. 2. Quaest. in hoc cap.
    ↩

24. LIB. 1. Cap. 6. ↩