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    Re: How Worsley Navigated
    From: George Huxtable
    Date: 2009 Mar 2, 00:22 -0000

    Brad has now clarified that Worsley observation for 7 May, and things are 
    starting to fit together. I look forward to seeing a transcription of the 
    rest of that page to fill in the jigsaw.
    
    A few more suggestions for Brad to ponder-
    
    At the top, against "Bird Island", he has given N56E68W. I wonder if this 
    might instead be transcribed as N56E (that is, a course of 56� E from North, 
    or 056�), followed by 68 M, rather than 68W. That might correspond to 
    course-and-distance to Bird Island, and then another 53 miles to Leith, 
    adding up to 121 miles altogether to Leith. Just a thought.
    
    At the right-hand end of a long line of obscure numbers, ending with 13.0 = 
    23', is this perhaps stating that at that latitude, 13.0 miles corresponds 
    to 23' of longitude, which is nearly, if not precisely, true. Just before 
    that does it perhaps read N68�E, corresponding to a course being made?
    
    Just below the chronometer reading is the figure of 13, which I take to be 
    chronometer error of exactly 13 minutes and zero seconds. It would be 
    interesting to see if this number changes each day by a few seconds, due to 
    the chronometer rate being inexact.
    
    Just below the sextant reading is a figure of 8', which I expect might be 
    Worsley's routine figure for overall sextant correction, in which case it 
    should be just about the same each time, except perhaps for a bit of 
    refraction.
    
    Brad might keep an eye open for these matters.
    
    Brad wrote- "The reduction provided was not the 9:45 AM reduction, and yes, 
    there is a notation in the log about how indistint the sun was for that 
    observation."
    In Worsley's text, what he said was that it was the horizon that was misty 
    at 9.45 am, and then the Sun limb was clear. It was the noon observation 
    that was affected by a blurry Sun.
    
    George.
    
    contact George Huxtable, at  george{at}hux.me.uk
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ----- Original Message ----- 
    From: 
    To: 
    Sent: Sunday, March 01, 2009 9:25 PM
    Subject: [NavList 7496] Re: [NavList 7468]Re: How Worsley Navigated
    
    
    
    Hi George
    
    There are three observations and therefore 3 reductions on that day and 
    page.  I chose the last one, because it was the easiest to transcribe. Ha! 
    Its all relative, you should see some of the pages.
    
    The reduction provided was not the 9:45 AM reduction, and yes, there is a 
    notation in the log about how indistint the sun was for that observation. 
    There is a second observation around noon, also not provided in the 
    transcription. Finally, there is the third observation this day, which is 
    part of the transcript provided.  Worsley is not consistent with regards to 
    the page/day scheme.  Some pages have as many as three days.  This page has 
    three observations.
    
    I wanted to help your understanding.  It is clear that the written accounts 
    in the books are not providing line for line accuracy relative to the 
    logbook.  This is clearly a case of just that kind of writer's license.
    
    To re-iterate, there are 3 observations on this day.  This is a PM 
    observation.  I have not provided a transcript of the entire page, rather, 
    just the one that was easiest (ha!) to transcribe.
    
    Best Regards
    Brad
    
    
    
    
    
    
    
    
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