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Brad, you wrote:
"This is nothing more than good old Saint Hilaire.  We wouldn't try this on a 
plotting sheet, simply because all the lines are at a relatively shallow 
angle.  Further, 25 LOPS with 24 advanced LOPS might confuse the living heck 
out of me, especially when I go for the "cocked hat"."

Well, at a fundamental level, everything is "good old St. Hilaire". :-) But 
there's a little more to it than just plotting the "cocked hat". There is no 
such thing for a dozen sights. Navigators accustomed to plotting a standard 
LOP fix would be left quite helpless when faced with these sights, and that's 
probably why this concept is largely unknown. Does that mean there are no 
options?

On a different matter, you wrote:
"For similar reasons, the Latitude by Double Altitude methods espoused by 
Bowditch fell out of favor."

Actually, it appears that it was never "in" favor in any real sense. While 
latitude by double altitudes was popular among land-based nautical 
astronomers and mathematicians, I've never seen any evidence that it was used 
by practicing navigators (except in classroom exercises). I'm sure it was 
used occasionally at sea --everything is eventually. But its inclusion in 
navigation manuals did not reflect "normal" practice.

And you wrote:
"This is very evident in the 4th method (variance of declination permitted).  
That method is twice as long as any other and certainly longer than a lunar."

There was great competition among the authors of these navigation manuals. 
Even when one method of working such a problem was more than enough in 
practice, the publishers could advertise these additional methods and 
increase their sales. It's important to remember that "epitomes of 
navigation" were usually private publications back in the 18th and 19th 
centuries.

And you concluded:
"The 'rapid fire fix', at least for me, falls into that category.  Yes, a 
computer can perform the calculation.  A human, not so much!"

First, bear in mind that MANY people work their fixes using a computing 
device, for all sorts of different reasons. There's nothing wrong with it. It 
may defy the concept of using celestial as a purely non-electronic backup, 
but there are practical cases where it could indeed be used as a backup, and 
there are also circumstances (like ocean racing) where there is no reason to 
avoid electronic solutions. 

Second, Brad, the fact that you have now come to understand that a "rapid-fire 
fix" is possible (and not heresy) by seeing it done in software does not 
imply that software is the only way to go. As I noted in my first post on the 
topic, getting latitude AND longitude by taking a bunch of sights around noon 
is no more than one special case of a rapid-fire case. But in the case of 
lat/lon at noon, there are graphical ways to work the sight which, not only 
do not require software, but are in fact extremely easy even for beginners to 
work.

And there remains a question: are there any other special cases of the 
rapid-fire fix that can be worked by some simple, graphical means? Any ideas?

-FER



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