NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Joshua Slocum's navigational methods
From: Frank Reed
Date: 2005 Apr 16, 01:56 EDT
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 today. 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. -FER http://www.HistoricalAtlas.com/lunars