This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1760 edition. Excerpt: ...above. Who fays further, " If the true Distance from the Vertex be taken for the np" parent, and t J.-Parallax in Altitude be found from it, that true Distance " bring increased by this Parallaxtmay be taken for the apparent; and " the Parallax thence found tvil/be very near the Truth. But surely Mr. Morris ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1760 edition. Excerpt: ...above. Who fays further, " If the true Distance from the Vertex be taken for the np" parent, and t J.-Parallax in Altitude be found from it, that true Distance " bring increased by this Parallaxtmay be taken for the apparent; and " the Parallax thence found tvil/be very near the Truth. But surely Mr. Morris could not take the foregoing Rule from the accurate Dr. BradUy; seeing, in the foregoing Instance, that it's Error is 22" of a Degree, a greater Error than the said Precept and Preface Writer to Dr. Halley's Tables, has detected in that Author, by his using the apparent instead of the true Diameter of the Moon, for reducing the J's apparent Right Ascension and Longitude observed to ' her true Right Ascension and Longitude of her Center, from the Earth's Center. ameters from ) to the Earth's Cen. J 62'5' '- &c By the fame Rule, the greatest Distance of the Moon is found, as follows. AsSine least Hor. Parallax.. 0 53' 19" co. 1.8080729 To Cosine Altitude 0 vim. S. 900 or Radius.. 10.0000000 So the Semi Diameter Earth... I. 00000000 To the N. of Earth's Diameter from J to ) 64,279 1.8080729 the Earth's Center J the greatest Dist. Likewise the least Distance thus. You may measure it at Full Moon by the Micrometer, from Observation. Or you may compute it by observing the Time the full Moon takes up in pasting the Meridian, on a given Circle of Declination, as follows. PROPORTION. As the Interval, of Time betwixt the Moon's two next Passages through the fame Meridian, it to the Interval os' Time observed, of the Passage of the Moon's whole Dislc, or kVest and East Limbs, over the fame Meridian, so it 3600 to the Mir.utet and Seconds of Equator pasting the Meridian while the Moon pastes it. Again, As Radius is to...
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