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    Joshua Slocum's Lunar (just ONE)
    From: Frank Reed
    Date: 2005 Apr 18, 00:37 EDT

    I asked sixteen months ago if anyone knew of any  actual evidence regarding
    Slocum's use of lunars for finding longitude on his  circumnavigation.
    Amazingly, there is, sitting in plain sight. And it was in  probably the most obvious
    place: the best biography of Joshua  Slocum...
    
    Walter Magnes Teller spent many years researching the life of  Joshua Slocum
    and his second bipgraphy of the man had the simple title "Joshua  Slocum".
    Teller was interested in the man's life and his seamanship but he took  no
    particular interest in his navigational methods. Yet hidden in one of  Slocum's own
    letters, sent home late in the circumnavigation, is exactly the  sort of
    documentary evidence I was hoping to find. About two-thirds of the way  through his
    circumnavigation, Slocum spent an afternoon at the beach in the  tropics
    south of Sumatra to write a letter home. In it he marveled at the  success of his
    navigation. It was August 20, 1897 (Slocum had left New England  28 months
    earlier and would return home in 10 months) and his boat was tied up  to a tree
    in the Keeling-Cocos islands about 750 miles south of Sumatra. On that
    afternoon he wrote to a friend in New York City about his experiences. Here's an
    extract:
    "Looking over the journals of all the old voyagers I see  none, working the
    old fashioned methods, so nearly correct as the Spray has been  in making her
    landfalls - seven times now in succession. I never did better when  I had even
    the best of chronometers and officers to assist - now you tell me  where it
    comes in? my "chro" is a one-dollar tin clock! And of course is almost  no time
    piece at all - I have to boil her often to keep her at it, from noon to  noon,
    through the months. The one thing certain about my sea reckonings: They  are
    not kept with slavish application at all and I have been right every time  and
    seemed to know that I was right; Even a lunar observation (so far have taken
    only one on the voyage) taken, of course, alone, was practically correct, I
    found, a few hours later, when I made the land. There was not a difference of
    five miles between Lunar obvs dead reckoning and the true position of the
    vessel  assuming the longitude of the Marquesas to be correct."
    
    There is, of  course, a possibility that he took another lunar after this
    date before he made  it back to New England. I give it 50-50 odds...
    
    I hope the point is  clear. Joshua Slocum did NOT circumnavigate the globe
    "using lunars". His  circumnavigation was an example of expert navigation and
    seamanship, but it is  connected only distantly to the era when lunar distance
    sights were commonly  practiced at sea. Nevertheless, Slocum's romantic and
    personal commentary on his  singular lunar observation near the Marquesas still
    stands as the best epitaph  we could hope to have for the long lost  lunars.
    
    -FER
    http://www.HistoricalAtlas.com/lunars
    
    
    

       
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