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    Re: Baffled by Baffin
    From: tony
    Date: 2005 Nov 24, 10:00 +0000

    Bruce. Thank you for your message.
    George. Here is the information your require:
    (1) Baffin spent the day before (8th July 1612) marking out a meridian line
    on a small island. On this occasion, he doesn?t explain his method but marks
    the extremities of the line with long plumblines.
    (2)The latitude was 65 20. The altitude was 8 51 The declination was not
    given on this occasion but, when given, his declinations are always about 10
    to 11 days out which I guess is caused by the Julian calendar. On that basis
    his declination is about 20 7 N.  By spherical trig, the LHA =115.386 or 7h
    42m. As he always uses a 12 hour clock and always refers to time as the
    hours from midnight or from midday, this fits in neatly with his time of 4
    17 24.
    (3) Even if he has made a slip in his description of the moon?s movement,
    how can the ?time? at London be greater. Being earlier in the day, the hour
    angle at London between the moon and the sun must be greater and the time
    earlier. But he gives the ?time? by Searle?s ephemerides to be 4 25 34 (an
    hour angle of 113.6).
    This is what is puzzling me. I would love to see the entry in the
    ephemerides for 9th July 1612! This problem doesn't arise with later
    observations which are remarkable accurate, just this pioneering one.

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