NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Slocum's lunars
From: Frank Reed CT
Date: 2003 Dec 13, 16:37 EST
From: Frank Reed CT
Date: 2003 Dec 13, 16:37 EST
Hello Jan,
Would you agree that Slocum was saying that he took only ONE lunar on the run from Juan Fernandez to the Marquesas? Otherwise, why would he marvel at the fact that the two positions (by DR and by lunar) were in such close agreement... What would you describe as his motivation for doing this sight at this time? What did you think of my speculation that he was getting stir crazy (a little "cabin fever") from the length and boredom of that passage. His description of the sights appears to suggest that he sighted land almost immediately after doing his lunar.
There are certain long legs in his voyage where we know by his own words that Slocum did no lunars (crossing the Atlantic on the first leg, for example). There are others where the evidence is strongly against lunars. It appears, from my reading, that he did only one on that 46 day run from Juan Fernandez. Where are the holes? When did he sneak them in?
Regarding he word "science", here's another issue to consider: the lunar distance method was intended to be almost a "rote" activity --something that a navigator could be trained to do, robotically-- and it would be IF he was in practice. By contrast, detecting an offshore current and thus determining one's longitude requires a degree of knowledge of the behavior of the oceans. Now here's the tough question: at the close of the 19th century, which one would have been called "science"?
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
Would you agree that Slocum was saying that he took only ONE lunar on the run from Juan Fernandez to the Marquesas? Otherwise, why would he marvel at the fact that the two positions (by DR and by lunar) were in such close agreement... What would you describe as his motivation for doing this sight at this time? What did you think of my speculation that he was getting stir crazy (a little "cabin fever") from the length and boredom of that passage. His description of the sights appears to suggest that he sighted land almost immediately after doing his lunar.
There are certain long legs in his voyage where we know by his own words that Slocum did no lunars (crossing the Atlantic on the first leg, for example). There are others where the evidence is strongly against lunars. It appears, from my reading, that he did only one on that 46 day run from Juan Fernandez. Where are the holes? When did he sneak them in?
Regarding he word "science", here's another issue to consider: the lunar distance method was intended to be almost a "rote" activity --something that a navigator could be trained to do, robotically-- and it would be IF he was in practice. By contrast, detecting an offshore current and thus determining one's longitude requires a degree of knowledge of the behavior of the oceans. Now here's the tough question: at the close of the 19th century, which one would have been called "science"?
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois