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181)
then given Diameters, of the Moon, and of the [[underlined] Space [[/underlined]] in the Celestial Sphere [[underlined]] intercepted [[/underlined]] by her Interposition, would be equal to four times the horizontal Refraction in her Atmosphere.
7. So then, in the Projection made upon the Plane IX for an Eclipse of a fixed Star, having CE (Fig. [[strikethrough]] II. [[/strikethrough]] [[insertion]] 49. [[/insertion]] in Minutes and Seconds, for the Moon's apparent or increased Semidiameter; and CF, in Minutes and Seconds, for the apparent Semidiameter of the Space hidden by the Moon in the Sphere of the fixed Stars, and best fitted to the Universality of the Phenomena; let us describe about the Center C the Circles ƒFSƒ, and LseEMIiS. And the unchangeable Arc eƒ or iS, taken in Minutes and Seconds upon the Radius eC or iC, will always be equal to twice the horizontal Refraction of the Rays of Light in the Moon's Atmosphere.
8. But let the Maps or Tables of the Places of the fixed Stars be wholly made, independently of any Passages of the Moon under them. Or else, in the making of those Tables, let a proper Diminution of the Space hidden by the Moon, in the Celestial Sphere, be taken into Consideration. For otherwise we may be exposed to very great and dangerous Errors.
9. Likewise (Fig. [[strikethrough]] I [[/strikethrough]] [[insertion]] 45. [[/insertion]] in an ordinary Projection transferred to the Plane XI., for a total or proper Eclipse of the Sun, let a Circle (Rad. NI) represent the Moon, for any Moment during the total Obscuration, according to the Suppositions and Rules, which are commonly followed in those Projections; but