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    Re: Confusion in NAO sight reduction tables...?
    From: George Huxtable
    Date: 2006 Sep 12, 15:33 -0500

    Geoffrey Kolbe asked, about these words in the Nautical Almanac-

    Suppose A = 74° 45'.  "Set A° = the nearest whole degree of A and A' =
    minutes part of A."

    Would you set A° to 74 or 75?

    The instructions on the use of the concise sight reduction tables in
    Nautical Almanac contains the sentence in quotes. (At least it does in
    1999 edition of the NA, the latest I have. If the NA now says
    different, I would be obliged if someone would say please..... Thanks)


    It says exactly the same, on page 284 of the 2005 Nautical Almanac. I
    don't have this year's.

    Geoffrey continued-

    If it said, "Set A° = the nearest whole degree to A....", the answer
    clearly be 75.

    If it said, "Set A° = the whole degree part of A....", the answer
    clearly be 74.

    The correct answer is 74. But on an initial reading of, "Set A° to the
    nearest whole degree of A...", I would have set A° = 75. I find that
    "nearest" confuses the issue.

    Am I alone in this?


    I agree completely. It's worse than confusing, it's positively
    misleading. I would have interpreted it just as Geoffrey did at first

    I suggest that Geoffrey should bring it to the attention of Catherine
    Hohenkerk, at HM Nautical Almanac Office. She has recently moved
    office to the Admiraly establishment at Taunton, in Somerset, but no
    doubt a note addressed to her previous address would get there

    That would be to HMNAO, Rutherford Appleton Laboratory, Chilton,
    Didcot, Oxon OX11 0QX.


    contact George Huxtable at george@huxtable.u-net.com
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

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