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System and the motion of the Earth round the Sun, to a Demonstration, [[may be?]] observed in [[underlined]] Saturn [[/underlined]] and [[underlined]] Jupiter [[/underlined]] every year; and in [[underlined]] Mars [[/underlined]] and [[underlined]] Venus [[/underlined]] once in two years.

3. But there is still a [[underlined]] more noble Argument [[/underlined]], the [[underlined]] Times [[/underlined]] of the Revolutions of the Planets round the Sun, and their [[underlined]] Distances [[/underlined]] from him, are so connected by a certain Proportion, which flows from a Natural Necessity, that one may venture to say, it is either Ignorance, or determined Obstinacy, that makes Men place the Earth in the Center of the System, since such a Disposition would ruin the most beautiful Proportion, and struggles (unsuccessfully) against the strongest Necessity. — The Proportion is this, [[underlined]] The Squares of the periodical Times of the Planets round the Sun are always as the Cubes of their Distances from him. [[/underlined]] (*) Baxter's C.P.  

4. M.^r [[underlined]] Flamsted [[/underlined]] (in his Letter ^sent to D.^r Wallis, the 20th of December 1698, [[strikethrough]] and [[/strikethrough]] published in D.^r [[underlined]] Wallis's Mathematical Works [[/underlined]] Vol. 3. says he) found the Annual Parallax of the Pole-Star 40 or 45 Seconds. But as his Instrument & steady position of the wall, to which it was fixed, are to be questioned; I should rather rely upon the proof drawn from several Stars appear^=ing Split, double or triple, at one time of the year, and one or single at another, as the Celebrated Astronomer M.^r [[underlined]] Cassini [[/underlined]] observed, that, the First of Aries appear as one single Star, but at another time, when the Earth was in its opposite point of [[strikethrough]] ?orbit [[/strikethrough]] her Orbit, it appear Split into two equal ones, distant from each other about one of their breadth's. He also observed the like [[strikethrough]] in the first [[/strikethrough]] from that in the Head of the first of the [[underlined]] Gemini [[/underlined]],that in Orion's Sword, & Belt, and some of the Pleiades, to be three or four times Split. 
Ozanam's Cour^e. of Math. Vol. 5 P.^r.I.p. 95. also Gregories Astronomy Vol.1 and 9. Prop. 5A. p.499.

5.Since the Orbits of the inferior Planets [[underlined]] Mercury [[/underlined]] and [[underlined]] Venus [[/underlined]]  in the [[underlined]] Ptolomaic [[/underlined]] Hypothesis are contained within that of the Sun, they can never be seen beyond the Sun, which they are observed to do as often as on this side of him: it likewise thence [[strikethrough]] also [[/strikethrough]] follows, that the [[underlined]] Sun [[/underlined]] may be in the [[underlined]] West [[/underlined]], [[underlined]] Mercury [[/underlined]] in the [[underlined]] East [[/underlined]] and [[underlined]] Venus [[/underlined]] in the [[underlined]] South [[/underlined]], at the same time; which are Aspects that have never yet been observed. But on the contrary the greatest Elongation of [[underlined]] Mercury [[/underlined]] is never more than 21 or 22 degrees, & of [[underlined]] Venus [[/underlined]] 47 or 48 degrees, whereby the Absurdity of the [[underlined]] Ptolomaic System [[/underlined]] is incontestably shewn. 
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