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167 
But that Refraction may be found also immediately or directly, by the Length or Duration of the sensibly close Contact of a fixed Star &c, with the apparent Limb of Disc of the Moon.
^[[A method to find the difference of Refactions in Summer & Winder, or at different Elevations or in different Climates is practicable.]]
     14. And since Observators may live in various Climates, and at different Heights above the Level of the Sea; and the Refractions in our Atmosphere may be different in Summer and in Winter; I contrived a Method how to find those Refractions, not by an Hypothesis, but by actual Observations. These Observations would be very useful, at least for Astronomers living in Royal Observatories, where, I should think, nothing ought to be neglected, that can contribute towards making their Observations accurate.
^Fig. 43. Previous considerations to determine the diameters of [[image - circle with dot in center]], [[image - crescent moon]], & [[image - circle bisected with horizontal line]].
     15. Let C be the Center of the Earth OQ[[F]]FNO; ON her Diameter; and OXH or OxH a Ray of Light horizontal in the Point O, and prolonged [[underline]]in infinitum[[/underline]] on each Side of O. Let OX or Ox be the Curve described by the Ray, as long as its Curvature is of the least Consideration. And let XH or xH Tangent of the Curve OX or Ox be sensibly rectilinear. And thus the right Line OXx will make with the Horizon of the Point O an Angle of 17' Minutes, equal to half the Refraction of an horizontal Ray in our Atmosphere. And let the Line CQP cut at right Angles HX and Hx in P and P, and the Circle OQFN in Q.
     16. Taking then for Radius CP, let us conceive about the Center C the Circle P[[a]]VBADGYN{{V]]GDABVP. And this Circle will give the Apparent Disc of the Earth as increased by the Refraction. And let us consider the Earth as [[?]]

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Wasn't sure if I was to include the page number at the top left, so I did. Wasn't sure how to incorporate marginalia given that both the document and the notes are handwritten. Followed the protocol for Handwritten Notes at https://transcription.si.edu/instructions#basic Wasn't sure how to treat symbols within marginalia. Followed protocol for Images at https://transcription.si.edu/instructions#basic