Page:Description and Use of a New Celestial Planisphere.pdf/43

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of the Ecliptic, at an Angle of 5° 18' at the moſt; the Moon never remains in the Ecliptic, but interſects it twice in a month, in the points called her Nodes, or the Head and Tail of the Dragon; or, theſe are the points in which the Moon's Orbit biſects the Plane of the Ecliptic, and while ſhe is in that half of her Orbit, which is on the South ſide of the Ecliptic, ſhe is ſaid to have South Latitude; and the point of the Ecliptic where the Moon paſſeth out of South, into North Latitude, is called her North Node, or Head of the Dragon, and then ſhe hath North Latitude, till ſhe arrives at her South Node, or, to the Dragon's Tail. The Nodes of the other Planets, according to Geocentric Viſion, are, in thoſe points of the Ecliptic where they have no Latitude, which are ſeen in the Nautical Almanac. I need not premiſe farther, in order to this Problem.

Required the Moon's true place on Sept. 15th, 1802, at 7h 24m, P. M. Find in the Nautical, or in any good Ephemeris, her Longitude at noon on the 15th, 1s 10° 49', and ſubtract it from her Longitude on the 16th, at noon, 1s 24° 41', and the difference is, 0s 13° 52'; then ſay, by the rule of proportion, if 24h give this Arc 0s 13° 52', what will the time from noon, 7h 21m give?—Anſwer, 4° 16', which, added to her Longitude the 15th, at noon, makes it 1s 15° 5', her true and corrected Longitude at the hour and minute required. But note! this is not the moon's true place in the Zodiac; for, against the 15th at noon, ſhe hath 4° 33" North Latitude, which, ſubtract from her Latitude the