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each other, as seen from the Earth, in the other. And they use the Symbol for the Trine Aspect, that is, when the Planets are a third part of the Ecliptic distant from one another, viz. 4 Signs; if they are but 3 Signs apart, that Aspect is called Quartile, denoted by o ; if but 2 Signs from each other, it is called a Sextile, and is thewn by this Mark *; if they are in Conjunction, it is shewn by 6, and if in Opposition by 8. And the Number placed by the Symbol, Thews the Hour after Noon, when that Afpect happens.

Euphrof. I believe I understand all that you have said, Cleonicus; but let me try if I can make it out by Experiment. The Lunar Aspects.

Aspects lol 2

at the Earth.

olol

D Perig.

*

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I observe against the 26th of December (to use the fame Example as before) in the Column under Jupiter 4 there is placed ó 18, which I apprehend denotes the Planet is in Conjunction with the Moon at 18 Hours after Noon But now, as there are but 12 Hours from Noon to Midnight, pray, what am I to understand by the 18th Hour, Cleonicus

Cleon. Why you are to reckon 18 Hours from Noon of the 26th ; 12 of which will bring you to Midnight, and the other 6 will make 6 o'Clock in the Morning of the following Day; so that the Conjunction happens on the 27th of December at 6 in the Morning.

Euphrof. Poh, that I could not think on so easy a Thing as that-well, what is the next Lunar Aspect that I see against the same Day—it is o 7, in the Column of o, by which I see Mars will be in its Quartile Aspect with the Moon, or 4 Signs from her, at 70'Clock that NightAgain: I see in the Column of 8, the Aspect * 19, shewing Mercury to be in Sextile with the Moon, atlet me think-19 is equal to 12 and 7-Oh, at 7 o'Clock the next Day.

Cleon. Very right; one Example more of the AspeEts at the Earth will make you a perfect Mistress of this part of the Science of the Stars.

Euphrol. That gives me no Trouble ; for against the 25th Day, I see the Characters * 4$, which thew that Jupiter 24 and Mercury $ feen from the Earth, have a Sextile Aspect *, or are two Signs distant from each other.

Cleon. Very well, and this you see confirmed by the Geocentric Planetarium, and also by the Table of Geocentric Motions, for the Place of 4 is there 26° : 18' of Libra -, and the Place of Mercury is 15° : 41' of

Sagittarius, which is near 2 Signs or 60 Degrees from the other. And as you are now ready in the Use of the Ephemeris, and can find the places and Aspects of the Planets for any given Day, as they are seen, both from the Sun and Earth, we may proceed to the Use of the Stellated Planetarium, which is somewhat different from what you have yet seen, and this Ihall be the Subject of the next Conversation,

SexCleon. Veranetarium, the Place Me

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DIALOGUE XIV. On the Use of the STELLATED PLANETARIUM

Euphroyne. QINCE I last saw the Planetarium, I observe you

have made an Addition to it; pray, what means that Hoop about it, with so many small Stars ?

Cleon. That is to answer the Purpose I have often mentioned to you, of shewing more plainly and directly the Manner in which the Planets must necessarily appear to us to go forwards and backwards, and at Times be Stationary, among the Stars in that part of the Heavens through which they pass ; which Stars are thofe engraved on the Hoop, and this stellated Zone will therefore fitly represent the artificial ZODIAC of the Planets.

Euphrof. You have indeed often promised me the Pleafure of those Appearances in this Way, which I presume will be more natural than those in which I have already viewed them. But I observe, you have only the three Planets next the Sun, in the Planetarium now.

Çleon. They will be sufficient for the present; and you will take Notice that the Wire which pafles from the Earth through the Planet Mercury to the starry Zodiac, does represent a Ray of Light, by which the Planet is seen by the Eye; and as the Planet moves on the Instrument it will point out the apparent Place of the Planet among the Stars, just as a Ray of Light shews the apparent Place of the real Planet in the Heavens.

Euphrof. I see the Congruity of such a Representation; and I farther observe, you have placed these three Planets at their proper or proportional Diftances from the Center of the Sun.

Cleon. I have placed them at their true Distances that you may see the Times employed in their direct and retrograde Motions, and their stationary Aspects are the very same in the Planetarium as in the Heavens, or in the Ephemeris, where the said Motions are all minuted down very punctually.

Euphrof. I fhall be pleased with repeating this aftronomical Praxis in a different Way from that of the Geocen

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