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    Joshua Slocum's navigational methods
    From: Frank Reed
    Date: 2005 Apr 16, 01:56 EDT

    Joshua Slocum was the first solo  circumnavigator. His tale of his voyage in
    the late 1890s, "Sailing Alone Around  the World", is an adventure classic.
    Because its copyright has long since  expired, you can read it online or
    download it from various sites on the  Internet, and there are still print versions
    available. Highly  recommended!
    In SAATW Slocum delivers one of the most quotable and most  quoted tributes
    to the practice of finding longitude by lunar distances. In a  longer passage,
    well worth reading, he wrote:
    "The work of the  lunarian, though seldom practised in these days of
    chronometers, is beautifully  edifying, and there is nothing in the realm of
    navigation that lifts one's heart  up more in adoration." And most fans of lunars today
    feel the same way.
    A  great many people who have read Slocum's book have concluded, mistakenly I
     contend, that Slocum got his longitude throughout this epic voyage primarily
    by  lunar distance observations. They reason that since he had only a cheap
    "tin  clock" and no chronometer aboard and mentions lunars so fondly in this
    one  passage, he must have been taking lunar sights on a regular basis. For
    example,  a bit over ten years ago (according to a google groups search) Dan Hogan
    wrote  on the rec.boats newsgroup, "Yeah It wasn't much of a boat, BUT, he
    was one heck  of sailor. The reason he didn't need an accurate time piece was
    that he used  Lunars for his celestial navigation." Or in the recent book "The
    Race", Tim  Zimmerman wrote, "Slocum resorted to calculating his longitude
    using the lunar  distance method, an extremely complicated procedure ..." (the
    idea that the  method is "extremely complicated" is a separate myth... for
    another day). And on  this list in 2002, George Huxtable wrote, "Joshua Slocum, who
    sailed around the  world single-handed at the very end of the 1800s, used
    lunars to do so (with  much latitude-sailing)."
    I raised this issue about a week after I joined  this list in December, 2003.
    There is no doubt that Slocum used lunars on one  afternoon in the Pacific.
    And there is no doubt that he wrote an eloquent  epitaph (quoted in part above)
    for the old lunar distance method. But the idea  that Slocum completed his
    circumnavigation *because* he used lunars, or that he  must have used lunars
    extensively *because* he had no chronometer is, in fact,  mistaken. Slocum kept
    his longitude by dead reckoning and says so rather  clearly, I think, in his
    book. His single lunar observation one afternoon in the  Pacific was not so
    different from a modern navigator's use of lunars --something  done for fun,
    challenge, historical experience, but not an essential component  of navigation
    There are a lot of people on the list now who were  not here in late 2003, so
    I would be curious to hear thoughts on Slocum's  navigational methods whether
    you were following the list then or not. If you  haven't read SAATW, you
    should. Go do it now. It's great fun.
    And if  anyone has any evidence to bring to bear on the issue of whether
    Slocum used  lunars more than once, I would be very interested to hear it. I've
    found one  interesting tidbit which I'll transcribe if there's  interest.

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