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a. Mare Hyperboreum .
6. Paludes Hyperboreæ :
c. Sinus Hyperboreus
d. Mare Boum
e. Mare Medis

terraneum

9.

f. Pontus Euxinus
Palus Mestis.
h. Mare Caffium
i. Mare Adriaticu.
k. Propontis

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Asia Minor. r. Colchis

3. Sicilia t. Peleponesus u. Scythia

r. Persia. x. Arabia 4.Palestina. zEgyptus

&.Libya. a. Inf: Cercinna..

1. Mons Sinai. 2. M.Taurus. 3 M.Sepher. 4 MEtna. 5. M. Apenninus. 6. M. Olympus

This Scheme is the Face of the Moon as it appears through a Telel= cope at the Full, and as described by Hevelius; the Dark Parts are the Sea; the Bright Parts Land, and the long white streaks, the Illuminated top of Ridges of High Mountains.

The Spots here Described are for the main the same that are continually exposed to our sight, on Account of the exact adjustment of the Moons's Diurnal and Menftrual Revolutions, whereby almost the very sames Face is continually turned towards our Earth.

Isay nothing of the Librations discoverd in its Motions by Heveli= = us, which make the Parts sometimes hidden to appear to us and thereby afford is Bordering Inhabitants (if such therebe) the glori ous view of our Earth, which the more remote Ones can never en -joy without Traveling a great way for so uncomon a Prospect.

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That the Moon has an atmosphere about it we have lately discovered; but that atmosphere being very thin and only visible in Total Eclipfes of the Sun, it was not necebary to reprefentit here. Senex foulp :

or nearly in the proportion of 1000 to 2828, is the Time of its falling to the Center From which Demonstration it is eafy to derive the foregoing Numbers.

(11.) The Moon has Day, and Night, Summer and Winter, Mountains and Valleys, Land and Sea; as alfo an Air or Atmosphere, with Clouds and Vapours, and a Moon, and all after the fame manner, in general, that our Earth has them.

That the Moon has Day and Night, is evident from the conftant falling of the Sun's Light upon one Hemisphere of the Moon, and the removal of that Light, from East to West, quite round it, in a Synodical Month, and is vifible to our Eyes; which Space is therefore equal to an entire Nuxe, which is 29d, 12h. 44′, long by our Computations.

That the Moon has Summer and Winter, is evident from the Librations of its Body, North and South, which imply that its Axis is about 6 Degrees distant from that of the Ecliptick, as our Summer and Winter is made by the Declination of the Earth's Axis 23 Degrees from the fame Axis. Only it hence follows, that in the Moon, tho' the Day be near 30 times as long as ours, and the Year only equal to ours in duration; yet that Year is with much lefs Inequality of Seafons, of Heat in Summer, and Cold in Winter, than ours; on account of the much smaller Declination of the Moon's Axis, than of that of our Earth, as compar'd with the Axis of the Ecliptick.

That the Moon has Mountains and Valleys, every Body that has feen its Face through a Telefcope cannot but know; thefe Inequalities of

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its Surface, efpecially near the Limits of Light and Darkness, excepting the Full Moon, being to all moft obvious and fenfible; as are also a great Number of circular Cavities in other Places, into which the Sun may be perceiv'd to fhine, and caft a Shadow, (excepting near the Full Moon) as evidently as the Moon does fo here with us. Only it must be noted, that those who have meafur'd the Height of the Lunar Mountains, which we ftand here very conveniently to do, find them much higher, at leaft in proportion to its Semi-diameter, if not alfo in reality, than thofe of our Earth.

That the Moon has Land and Sea, or fome Parts full of Inequalities, like our Land, which ftrongly reflect Light; and others fmooth and plain, like our Seas, which reflect it more weakly, is, I think, now very clear, not only from the obvious diftinction which even the naked Eye makes between the rougher brighter Parts, and the smoother Spots, and which the Telescope does more fully confirm ; but more particularly from Mr. Derham's Noble ObfervaPref. p.51 tion, which I am inform'd was first made by Hevelius; that when the Limit of Light and Darknefs paffes over the brighter Parts, 'tis plainly. jagged and uneven; but ftrait and even when it paffes over the darker; which feems to me entirely to determine this Matter.

Aftro-
Theol.

That the Moon has an Air or Atmosphere encompaffing it round, is now, I think, very plain alfo, from its Appearance in Total Eclipfes of the Sun, the fitteft Times of all for its Obfervation, and efpecially from the two last Total Eclipfes, in 1706, and 1715, of which laft I have given a full Account to the World; and

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