Next message: Frank Reed: "Re: on finding Pitcairn Island"
(Revisiting a post from a week ago)
George H wrote:
"As I see it, however, Arnold's method, including standard refraction and
parallax in his tables I, II, and III, was inflexible in that it would have
been unable to adapt to such requirements."
Another thought on this:
The biggest issue with lunars was the first hurdle: getting people to try
them at all. And that means that efficient tabular methods that had no
complicated "cases" to learn were likelier to succeed in the navigatonal marketplace.
I've recently been looking over Thomson's Lunar tables (included in Bowditch for
most of the 19th century), and, like Arnold's and many others, they have no
provision for including non-standard refraction (temperature and pressure
variations) and only a primitive capability with respect to solar and planetary
parallax. That's apparently why Thomson included a second method in his original
tables. It's there for perfection-seeking navigators who wanted to throw in
every last little detail. His standard method, sleek and refined as it was,
produced results quickly and without a lot of fuss, and that's probably why it was
popular.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
