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    Re: Need help to track down errors
    From: Gary LaPook
    Date: 2008 Nov 13, 05:14 -0800

    I sent this email today to the government office that computed these
    Dear Mr. Doherty,
    Last year I called your attention to some errors I had found in the on-
    line version of  H.O.  249 for Hc's near zero and I checked recently
    and these appear now to have been corrected. However, when I was
    reviewing the updated version I found some additional errors.
    In volume 2 page 158 is completely wrong and appears to be a duplicate
    of page 152 and page 133 is also completely wrong and appears to be a
    duplicate of page 139! I suspect that there are many other similar
    errors hiding in this volume that my cursory review didn't reveal.
    Gary LaPook
    On Nov 13, 3:34 am, glap...@PACBELL.NET wrote:
    > Further comparison shows that page 133 is a duplicate of page 139!
    > gl
    > On Nov 13, 1:56 am, glap...@PACBELL.NET wrote:
    > > Ken,
    > > My copy, 1970 edition, doesn't have the error you pointed out. I then
    > > looked at all pages from 122 through 161 looking at the first entry on
    > > each of these pages and found additional differences between my print
    > > edition and the online version. Page 155 has a one minute different Hc
    > > as  does page 151 for the first entry but I didn't check other values.
    > > page 133 is completely different, all tabulations are different ! I
    > > computed several of the entries on page 133 and found that the online
    > > version has the erroneous values while my 1970 edition has the correct
    > > values.
    > > gl
    > > On Nov 12, 4:08 pm, Ken Gebhart  wrote:
    > > > To all List Members,
    > > > Need help to track down errors!
    > > > I have been made aware of  many errors on page 158 of Pub 249 Vol 2
    > > > Apparently all of the Hc values on the page are wrong!  For example,
    > > > for dec 0, LHA 0, Lat 26 (page 158), Hc is shown as 65 deg. When it
    > > > should be 64 deg by simple inspection.  All the other numbers are
    > > > also off by varying amounts as can be found by computation.  There
    > > > are some other errors too, of a different kind on other pages.  For
    > > > example, page 160.  Look at the column for dec 15 deg, and go down to
    > > > LHA 98.  By simple inspection you can see that there should be a
    > > > minus sign before Hc 00-25, but it is not there.  I believe this is
    > > > typical of many Hcs  near zero.
    > > > These errors are present in the US Government Edition, privately
    > > > published editions, and the PDF on the NGA website.  I have spoken to
    > > > the UK Almanac Office, and they report that the errors do not exist
    > > > in their equivalent to 249 V2, or their Rapid Sight Reduction Tables,
    > > > and can find no trace or knowledge of them.
    > > > I am asking anyone who has an older copy of this volume, to check it
    > > > for these errors and report the publication date.  Maybe we can track
    > > > down when they first appeared.  By the way, a friend did phone the
    > > > NGA to report this, and was told that �they would look into it�.
    > > > Thanks, Ken Gebhart
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