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    Re: Logs
    From: Arthur Pearson
    Date: 2003 Jun 10, 19:09 -0400

    For years I sailed with the Hurricane Island Outward Bound School in
    Maine.  In countless trips up and down the coast in 30' open
    sailing/rowing boats, we measured speed by timing a "chip" from bow to
    stern and dividing the seconds into 18.  Using a lobster pot yielded
    speed over the ground.  Using a small stick gave speed through the
    water. 6 seconds for the 30' from bow to stern indicated 3 knots. We
    crossed a lot of bays in the fog with nothing more accurate than that
    and hundreds of crews over many years did just fine finding the other
    side. I now sail a Drascombe Longboat and the only improvement I have
    made is to keep a 30' piece of string tied to small piece of wood so I
    always have my "chip".  Still works fine.
    -----Original Message-----
    From: Navigation Mailing List
    [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM] On Behalf Of Noyce, Bill
    Sent: Tuesday, June 10, 2003 3:47 PM
    Subject: Re: Logs
    > He then nipped the line which
    > caused the board to become more streamlined (parallel to the flow)  in
    > water and the line was reeled in. The number of knots counted equalled
    > speed.
    > Is there a description somewhere that would tell me how to duplicate
    such a
    > log?
    It sounds to me as if you have all you need to know.  A few more
    the "chip" is often a semicircle, with the round part down, and some
    attached to the low point to help keep it mostly submerged and upright.
    There are three attachment points: two form the bridle, and the third is
    a peg.  The three help keep the chip perpendicular to the line, and the
    peg pulls out when the line is "nipped", so it can be reeled in more
    The exact time for your sandglass isn't critical, but the spacing of the
    knots has to be made to match.  I believe the classic sandglass was 28
    seconds.  Leave some blank line so the chip can get settled and out of
    vessel's wake, then insert a starting mark (at which the man controlling
    the line would shout, "Turn!"), and space the knots at 6080*t/3600 feet,
    to measure nautical miles (6080 ft) per hour based on feet traveled in t
    seconds. (Hope I got the formula right.)
            -- Bill

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