The Nautical Almanac and Astronomical Ephemeris for the Year ...

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order of the Lords Commissioners of the Admiralty, 1819 - Nautical almanacs

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Page 125 - Columns of the second Page of the Month contain the Day of the Week and Month, as before; next follow the Sun's Longitude, right Ascension in Time, Declination, and the Equation of Time with its Difference from Day to Day.
Page 127 - Motion, such as that of Clocks and Watches ought to be. This Retardation or Acceleration of the Sun's coming to the Meridian is called the Equation of Time, and is contained in the last Column but one of Page II.
Page 125 - Increase : saying, as 24h is to the Hour from Noon reckoned by the Meridian of Greenwich, so is the daily Variation of the Sun's Longitude, to a fourth Number; which, added to the Sun's Longitude at the preceding Noon, gives the true Longitude at the given Time.
Page 127 - Column but one of Page II. and when applied according to its Title to the apparent Time, or that deduced immediately from the Sun, gives the mean or equated Time, whence the Error of a Clock or Watch may be found, and, if required, it may be corrected. If it be...
Page 129 - It was hoped that some Means might be found of using proper Telescopes on Shipboard to observe these Eclipses : and could this be effected, it would be of great service in ascertaining the Longitude of a Ship from time to time. In my voyage to Barbadoes, under the Directions of the COMMISSIONERS OF LONGITUDE, in 1763, I made a full trial of the late Mr.
Page 125 - Day are the same in this Method as in the civil Account at Noon, and from Noon till Midnight; but from Midnight till Noon they differ; for whereas in the civil Account a...

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