that white things, when moistned, do become more obscure, and draw towards a black Colour. Let but some Water be spilt upon a Floor (to make use of GALILAEUS his Example) and presently the moistned Bricks will appear of a darker Colour than the rest, because the water filling their pores, makes their surfaces plain and even; which consequently do unite the Rays, and direct them to one Point only. And seeing that fewer Rays are reflected from a Convex surface, than from one that is plain, the Light which from the Moon can be reflected to our Eyes, must be so inconsiderable in quantity and strength, as not to be so much as one 14000th part of her Dia∣meter.
II. What the Reason is of those bright parts which sometimes appear in the Moon. The Moon has some parts which are much brighter than the rest, and which do so strongly affect our Sight, as that they seem to be very distant from one another. Whence GASSEN∣DUS tells us, that about the 3d or 4th day after the New Moon, we may for the most part observe, beyond the lower point of her Body, at the distance of about a 27th part of her Circumference, a certain bright Point, and sometimes also a 2d and a 3d, at a greater distance, whilst the Intervals betwixt them continue still in obscurity.
These Appearances give us good ground to conclude, that there be Mountains in the Moon, seeing that with the assistance of a Telescope, the Ridges of several of them are perceived very bright, which cast a most thick shadow, and that greater or less, according as those Eminencies are more or less distant from the Confines, which sepa∣rate the enlightned part of the Moon from the dark. For it is observed, that these shadows decrease, according as the Illumination is increased, until that they do altogether vanish away upon the diffu∣sion of the Light over the whole Hemisphere. And after that the Lunar Beams are come to the other Hemisphere, the same Ridges or Tops of Mountains do appear again, and cast their sha∣dows, but towards an opposite Point. Which Appearances afford us an incontestable Proof, that the Moon hath her Mountains, as well as our Earth, whose Tops are illustrated by the Sun, and shed a great Light, whilst in the mean time her lower and more deprest parts, continue obsc••••e and dusky.
III. Whence proceeds that ap∣pearance of a Face, which is seen in the Moon. About the 6th day of the Moon, towards the Western part of it, there appears the Face of a Man, with a broad Fore-head, a crooked Nose, a wide Mouth, and Eyes deep sunk.
This Appearance is caused by several Spots, that are deprest between the foresaid Prominences. For seeing that the Mountains in the Moon, do far exceed ours in height, they accordingly pro∣ject great shadows, which renders their Intervals dark and obscure, and makes them look like spots residing in those places. This we find by Expe∣rience in the Mountainous parts of the Earth, which are thick set with Trees, and therefore appear more dark than bare and open Fields; because the Trees make a great shade, and hinder the Rays from proceeding further. Thus foras∣much as not only Rocks and Banks are discover'd in the Moon, but also very high Mountains; the shadows which they cast, may be so ranged as to represent the Fore-head, Nose, Mouth, Eyes, and Lips of a Man, but very deformed: Seeing that
it cannot be question'd, but that the even or plain parts of the Moon, which lye between the Mountains, are dark and reflect no Light at all towards us; and that therefore the spots, which represent to us the parts of some deformed Coun∣tenance, do not proceed from the Tops of the Mountains, but must rather be attributed to their Intervals, between which the shadows are pro∣jected.
IV. Why the Face of a Man, rather than any other fi∣gure, is perceived in the Moon. But if any one enquire further, how it comes to pass that when we behold the Moon, we seem to see the Face of a Man, with Eyes, Nose, Mouth, &c. when indeed there is no such thing there.
To this I answer, that no other Reason can be assign'd for this Appearance, save only that the Footsteps or Traces of a human Countenance, are so deeply imprest in our Brain, from our frequent, and almost continual beholding of the Faces of Men; that the Animal spirits, which have their Rendevous in the Brain, not being able to pene∣trate the other parts of it, because of their Re∣sistance, are easily turned aside, by the direct Light of the Moon imprest upon them, and made to betake themselves to those Traces, to which the Idea's of a human Face are linked by Nature. And tho' others seem to behold in the Moon, a Man standing, or any other Appearance, this is only to be attributed to their Imagination, which having been strongly imprest by such like Ob∣jects, have some Traces left in it, which are easily open'd again, by any thing that hath the least resemblance with them.
V. Why the Moon in∣creasing, appears with Teeth like a Saw. The Moon increasing, being look'd upon through a Telescope, doth appear rugged and, as it were, with Teeth like a Saw; as if in the very confines of the Luminous part of it, there were some rugged and uneven Bodies, that did termi∣nate that part of its surface.
The Reason is, because the Sun being then newly risen, and only darting his Rays side-ways, doth cast shadows towards the opposite part. And because this Section of the shadow is very unequal, because of the great variety and multiplicity of the Mountains against which the Solar Rays are reflected, the Face of the Moon must needs appear uneven and jagged.
VI. Why the Moon at the Full doth ap∣pear bright all over. No spots or shadows are discerned in the Moon, when she is at the Full; yea, those very parts which appear'd very black at the time of her Conjunction, do at the Full Moon appear most bright and refulgent.
The Reason is, because all the parts the Moon then discovers to us, are illuminated by the Sun, who being directly opposite to her, doth enlighten all her most abstruse parts: Or, if any of her parts, by reason of their bending downwards, con∣tinue unenlightned, the same are cover'd by some nearer Parts, which turned towards us and them, and so do not appear to us at that time. To which may be added, that those Intercals which before were shaded, do not only at the Full Moon receive the direct Rays of the Sun; but also the Beams which are reflected from the sides of the Moun∣tains, by which reflexion all the parts of the Moon cannot but appear white and refulgent to our Eyes.