NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lewis and Clark lunars: more 1803 Almanac data
From: Bruce Stark
Date: 2004 Apr 21, 23:47 EDT
From: Bruce Stark
Date: 2004 Apr 21, 23:47 EDT
Henry,
Thanks for getting down your old vernier octant to check my notion. Looks like my 15° interval idea doesn't fly. But now I don't think it was of any consequence. All that would be required for such a blunder would be that the 60° engraving would be on the part of the arc Lewis would have seen in the opening of the index arm.
As I recall, the moon was not long past full at the time of the observation. But George considered the wrong limb possibility and several other List member examined it too. It doesn't explain anything, not by itself anyway.
Quite a few graphical and mechanical methods of clearing the distance were invented. Seems like one was mentioned in an edition of Maskelyne's Requisite Tables. Janet Taylor invented one. Maybe it will come up in the Greenwich lecture on Mrs. Taylor that George posted us on.
I'd never heard of Arnold's Lunarian before. Sounds interesting.
Bruce
Thanks for getting down your old vernier octant to check my notion. Looks like my 15° interval idea doesn't fly. But now I don't think it was of any consequence. All that would be required for such a blunder would be that the 60° engraving would be on the part of the arc Lewis would have seen in the opening of the index arm.
As I recall, the moon was not long past full at the time of the observation. But George considered the wrong limb possibility and several other List member examined it too. It doesn't explain anything, not by itself anyway.
Quite a few graphical and mechanical methods of clearing the distance were invented. Seems like one was mentioned in an edition of Maskelyne's Requisite Tables. Janet Taylor invented one. Maybe it will come up in the Greenwich lecture on Mrs. Taylor that George posted us on.
I'd never heard of Arnold's Lunarian before. Sounds interesting.
Bruce