A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Sean C
Date: 2015 Mar 9, 20:50 -0700
I am trying to figure out if this method can be applied to a G.P. and A.P. which are in different hemispheres. So far, my experiments seem to indicate that it cannot. But I am content to wait for the arrival of the book so that I can perhaps gain a better understanding of this method's limitations.
Well, I read the whole book and was pleasantly surprised to find that this method is not limited to an A.P. and G.P. in the same hemisphere. I was actually on the right track already, I just didn't go far enough. I had supposed that there might be a way to solve the problem with this method if one were to 'move' the G.P. to the opposite hemisphere (i.e., the same hemisphere as the A.P.). Turns out, with the addition of a couple of minor steps, I was right.
Contrary to complicating matters, as some may view it, this book actually did help me to better understand the concepts behind solving the navigational triangle. I theorize that this is because I am an extremely visually oriented learner. Being able to visualize what is going on allows me to fully grasp the nuances of a problem, not just the fundamentals. The author even suggests that his method may be used alongside a set of tables for that very purpose:
...where this graphic solution is least precise, it is most practical as an adjunct to the usual solution by mathematical tables. [...] And when the student can actually draw the lines which mathematicians merely imagine, [...he] will have a far deeper understanding of navigation than workaday use of the tables can provide.
-Joseph Breed, NAVIGATION WITHOUT NUMBERS
In summary, I would highly recommend this book (if you can find it) to visually oriented students of cel-nav.
As a side note, I found it humorous that the book I purchased was on offer from a seller in Virginia, my state of residence. Upon reading it, I see that the author used a sample navigation problem which reads:
The U.S.S. Mississippi is making passage from Hampton Roads to Liverpool...
Hampton Roads is the part of Virginia in which I live. Just a few pages later, in another example, the ship is departing San Diego, where my girlfriend grew up. Coincidences like these amuse me. :)