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    Re: leap seconds a navigational hazard, says expert
    From: Richard M Pisko
    Date: 2003 Aug 12, 01:43 -0600

    On Sun, 10 Aug 2003 19:41:20 -0700, Brooke Clarke wrote:
    >It's about 15 feel long and a few feet wide as far as I can remember.
    >Where the hole is at the base of the skylight might be above the floor
    >by 12 -15 feet.
    >In the winter when the slant distance is long the image is dim so the
    >white 3x5 card makes it visible.
    >I tried a number of different hole sizes.  It's like a f-100 lens and
    >you get an image of the sun on the floor.  As the hole gets larger the
    >image gets brighter and fuzzier.
    Thank you, good information.  I do have an old book that I still like
    "Sundials -- Their Theory and Construction" by Albert E. Waugh; but I
    am glad to get more accurate and newer ideas.
    Richard ...

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