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fixed Stars by the Moon, the Diameters of the globes of the Moon and of the Earth, as increased by the horizontal Refractions proper to their Atmospheres, ought to have their Proportion always the same,[[underline]] viz[[/underline]]. as TF or DF to LL. And this Proportion will differ from the true and natural [[underline]] Propotion[[/underline]] of the Diameters of the solid globes themselves, only by the small [[underline]]Additions[[/underline]] like QP or fF &c. made to the Semidiameters of the Earth and of the Moon, upon ^account of^ the horizontal Refraction of Light in their Atmospheres. And having now the Knowledge of the Sun's Parallax, and of the Distance [[strikethrough]] between [[/strikethrough]] betwixt the Centers of the Earth and of the Moon so nearly; we may already determine pretty well that [[underline]]proportion[[/underline]] and those [[underline]]Additions[[/underline]], even by a proper Observation of a (total) Solar Eclipse. But Astronomers will be much wanting to themselves, not to say to the Public also; if both these Quantitys be not accurately known in a short Time, by means of proper Observations of the Passage of the Moon under some fixed Stars.
  4. In Eclipses of fixed Stars, the apparent [[underline]]Diameter[[/underline]] of the Moon [[underline]]found [[/underline]] by Astronomical Instruments, or by accurate Calculations fitted to an exact Theory, is the same as her increased Diameter apparent to the Eye: Which differs very little from her Mathematical apparent Diameter. But the Diameter of the Space hidden by the Moon in the Celestial Sphere must be made a great deal less, in the projection for Eclipses of fixed Stars, to answer universally the Phenomena of their Immersions and Emersions. And that Diminution amounts always, in the Sphere of fixed Stars, to one and the same Number of Minutes and Seconds, equal to four times the Refraction in the Moon's Horizon.