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Subject: Re: Preston's paper on Lewis & Clark's Navigation
From: Fred Hebard (Fred@XXX.XXX)
Date: Sat Jun 07 2003 - 19:29:56 EDT
On Saturday, Jun 7, 2003, at 19:06 US/Eastern, Fred Hebard wrote:
> The 45 degree problem wouldn't have arisen early in the journey.
Yes, a backsight with an octant would have been necessary near St.
Louis on May 21, when the expedition departed. The sun's altitude then
would be around 73 degrees, or 146 in an artificial horizon, too much
even for a sextant.
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