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From: George Huxtable (no email)
Date: Wed Apr 12 2006 - 16:56:13 EDT
Alex had written-
| There are several books (I know one!) and websites
| on the Lunars, all of them were extensively discussed
| on this list. The best website (on my opinioon) is
| www.clockwk.com/lunars/
and I asked him-
| > What is the one book on lunars that he refers to?
his reply was-
| Bruce Stark, Tables for clearing the LD's, 45 EU
| listed on
| www.navastro.fr/en/index.html?p236.html
| (Sorry, I did not mean to violate the list policy
| prohibiting advertising. Disclaimer: I have never seen the
| book. I judge from the advertising and ocasional references
| on this list).
======================
I have a few comments about what Alex has said above.
Although this list has done its best to prevent actual advertising (and with some success), I doubt if that term covers an honest
expression of opinion, in favour of a product or against. And that applies particularly to books, which are freely praised or
criticised on this list, just as they should be.
Alex did not mention the title of the book he was thinking of, until I forced it out of him. He was wise, in the circumstances. I
had taken it that he was perhaps endorsing a suitable account of lunars, for explaining matters to a beginner. But he wasn't; he was
just saying that he knew of just one modern work devoted to lunars. Bruce's work is the one, and Alex hasn't seen it.
I think we should make it clear, at this stage, what a reader will find in Bruce Stark's "Tables for clearing the Lunar Distance,
and finding GMT by sextant observation". It does exactly what it says on the cover. 98% of the book consists of tables of numbers.
It has been assembled, with great cunning and originality of thought, to lighten the arithmetical drudgery of converting
observations into positions. It does that job superlatively well; a very workable alternative to using solutions programmed on a
computer or calculator. It's available from Celestaire.
But it is NOT a work which describes or explains lunar distances in any detail; and I doubt whether even Bruce Stark would claim
that it did. There are half-a-dozen useful pages, about how to work the tables with the sextant observation, including a bit about
the general principles underlying the lunar distance method, with a smattering of history. But that's all. Anyone buying Bruce's
book on the understanding that it would teach him about the lunar distance method, would be disappointed when a big (and rather
expensive) work arrived at his door, full of numbers.
I wish that I could recommend an alternative for a beginner in lunars to read, but I can't. There isn't such a book. It doesn't
exist. It would be good if someone were to produce one, to do the same job for lunars, and for Nevil Maskelyne, that Dava Sobel did
for John Harrison and the chronometer. And do it better than she did (which would not be difficult).
There are bits in books, that help to explain lunars. We have discussed these before, but it will do no harm to go through them
again, for new members.
There's a chapter, by Derek Howse, in "The Quest for Longitude" (ed. Andrewes, Harvard 1996). That's the record of the proceedings
of a conference on that subject, which might have been dull, but isn't at all. Most of it is about the development of timepieces.
It's beautifully produced, though an expensive buy.
Howse has also contributed a chapter on "Navigation and Astronomy in the Voyages", to a book on Pacific exploration, edited by him,
"Background to discovery" (Univ. of California press, 1990). That chapter has a reasonable, though non-mathematical, account of
lunars.
There quite a big section on lunars in "A History of Nautical Astronomy", by Charles H Cotter (1968). This is thorough, but not easy
going in my view. That's fair enough; the lunar method takes quite a bit of explaining. As well as lunars, it has a full treatment
of other methods of celestial navigation. It has a serious defect, however, in that it's littered with errors in the technical
details. A list of known or suspected errors is available on request. Cotter is long out-of-print, and becoming rather rare, so it
has got rather pricy. If you find a secondhand copy at less than £50 ($80), you have done well. It's a mine of material, that can be
found nowhere else, except by digging through old publications in a good library.
Short sections on the lunar distance method can be found in "A history of the practice of navigation", by J B Hewson (Brown, 1951 to
1983) and in "A history of marine navigation", W E May, (Norton, 1973).
A book which has not (I think) been touched on here before, and which has a brief mention of lunars, is "Thinkers and Tinkers", by
Silvio A Bedini (1975, reprint 1983). This could be of particular interest to American readers, being about early American men of
science, which includes astronomers and nautical instrument makers. Lots of pictures of instruments. Bedini was Keeper of rare
books, at the Smithsonian.
If anyone can suggest other works that provide useful information about lunars, I would be pleased to hear of them.
George
==============
contact George Huxtable at
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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