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Sun's Parallax. But when Sir [[underline]] Isaac [[/underline]] came to Town, instead of entertaining the same Hope, he only said, That it would serve to determine the Excentricity of the Moon; but that the Revolution about the Sun spoiled all. This made me to neglect that Theorem, till the year 1735. And such was my Prepossession that when I found by it the Demonstration of an accurate Method for finding the Sun's Parallax, and my Calculation made it then of 2° 26' 23" 38" in reference to the Orbit of the Moon, I did write over - against my Demonstration, [[underline]] Hic videtur Error subesse, undecunque oriatur. [[/underline]] For I could not believe that the Parallax of the Sun was so great. But hitherto I have not been able to find any Paralogism in that Demonstration.
    8. Sir [[underline]] Isaac Newton [[/underline]] in his 26th Proposition, supposes the Moon to revolve in a circular Orbit concentric to the Earth: and argues upon that Supposition. But I shall suppose that the Center of the Moon does or might revolve, at certain select Times, or in certain Cases, in Orbits which may not depart from a Spherical and Stereographic Surface OLP. 
Which Supposition will come a great deal nearer the Truth. For by that means I may have a full Regard to the Moon's Excentricity CT. And wheresoever the Focus F or f may fall upon the Line PT, there it will remain fixed, during the whole Revolution of the Moon upon the said Surface. And so that Focus may be placed any where upon PT, according as the Observations, already made or to be made, or the Astronomical Tables, and the Opinions of Astronomers, or the Seasons of the year, or the Proportions which you allow to the Masses of the Sun and of the Earth, or else to the Lines LH and HI, or LH and HI may require. And at the same time the Gravitations of the Moon toward the Sun S and toward the Earth T will be, in any Point of the Spherical Surface OLP, accurately in the Proportion of

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