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    Re: Waterspouts.
    From: George Huxtable
    Date: 2003 Sep 21, 00:59 +0100

    Thanks to all that responded to my request for information about
    waterspouts. Putting them together, it shows that there's no "typical"
    waterspout, but the things come in all shapes and sizes, and degrees of
    danger.
    
    One message, sent off-list, included these interesting observations of a
    waterspout-
    
    >The waterspout passed some 100 yards away, and was an impressive
    >sight.  The surface of the sea mounded up where the spout
    >touched the water.
    
    This is very believable, indicating a large, very concentrated, drop in
    pressure at the base. A local drop in pressure by 100 mb would correspond
    to a surface hump about 3 feet high.
    
    >... The opinion of the
    >old time professionals ...  was
    >that it was dangerous because when it broke and the tons of water
    >that had been sucked up (and presumably were in tight liquid
    >state rather than mist) came crashing down it could crush any
    >boat under it.
    
    That opinion seems rather less realistic. The density of water in "tight
    liquid" form is such that even a perfect vacuum could only suck up a column
    about 30 feet high. Although from 100 yards away it may have looked as if
    it was comprised of liquid water, I think that dense salt spray is more
    likely, like rain in a very VERY heavy downpour, but even more so. Even so,
    no doubt it contained a great weight of water in droplet form, which if the
    waterspout broke above a vessel would result in an unpleasant, and perhaps
    dangerous, drenching.
    
    I have a half-memory, in the back of my mind, of a man o'war attempting to
    disrupt an approaching waterspout by firing guns in its direction. Whether
    this  account was fact or fiction, whether the attempt was successful or
    not, whether the guns fired blanks or shot, none of this I can recall. It
    could well have been in a Hornblower story. Does anyone recall such an
    account, anywhere?
    
    George.
    
    
    ================================================================
    contact George Huxtable by email at george---.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ================================================================
    
    
    

       
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