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    Re: Transcription of Worsley's Log
    From: Henry Halboth
    Date: 2009 Mar 18, 08:24 -0700
    Hi Brad + George
     
    I believe that I have deciphered Worsley's numbers for April 25th.. He is using the old style format for a Longitude time sight at Latitude 61.4 S, which I presume to mean 61-04 S. The numbers in the right hand column, although separated by decimal points are actually the logarithmic values applicable to the formula employed. I will recalculate and let you know the results asap. Depending on the sun's azimith at the time of observation, the Latitude used may not be that important to the correctness of the Longitude determined.
     
    By the way, until quiet recently at least, there appears to be an international difference of opinion as respects positions on Elephant Island.
     
    Regards,
     
    Henry

    --- On Tue, 3/17/09, bmorris@tactronics.com <bmorris@tactronics.com> wrote:

    From: bmorris@tactronics.com <bmorris@tactronics.com>
    Subject: [NavList 7664] Re: Transcription of Worsley's Log
    To: NavList@fer3.com
    Date: Tuesday, March 17, 2009, 9:19 PM


    Hi George

    I have calculated the chronometer error for Point Wild.  While not a substantial difference for the result from Cape Belsham, it continues show that Worsley had injected an error from the start.

    From Navigational chart 29104 "King George Island to Clarence Island", I determined the location of Point Wild to be Latitude South 61 degress 6 minutes and 15 seconds, Longitude West 54 degrees 52 minutes 12 seconds.  Point Wild is clearly marked on the chart.  I took the northernmost tip to be Worsley's location.

    With this location, we can solve for the chronometer error by injecting the correct latitude, altitude and chronometer value to solve for the correct longitude.

    The value I obtain is 13 minutes 21.2 seconds.  Since Worsley would not have been able to distinguish 0.2 seconds, lets call it 13 minutes 21 seconds even.  Compare this to 13 minutes 28.5 seconds for Cape Belsham, about 1 mile away. 

    Further, compare this to Worsley's value of 11 minutes 55 seconds.  Subtracting 11-55 from 13-21 yields 1 minute 26 seconds.  At 8.27 seconds per mile, he thinks he is about 11 miles further to the east than he really is.

    That disagrees with my earlier posting on miles, wherein I in-advertently added in a minute due to poor arithmetic skills. 

    Best Regards
    Brad


    Best Regards
    Brad



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