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My personal thanks to everyone who attended the  Navigation Weekend in
Mystic. The presentations were very successful, I thought.  And the free-wheeling
discussions, whether during Q&A sessions or over  dinner, were extremely
productive. I was pleased... :-)

We started  out on Friday with a tour of Mystic Seaport's Collections
Research Center, led  by Bill Peterson, Mystic Seaport's Senior Curator. Nearly a
secret, the CRC is  the "museum within the museum". It is housed in an old mill
building that, from  the outside, literally looks like an abandoned building.
Inside, it's keycard  access, climate control, and sliding doors. Clearly an
enormous investment. We  saw just a hint of Mystic Seaport's collection of
nautical instruments including  three reflecting circles, drawers full of old
telescopes, strange  star-identification devices. In addition we saw hundreds of
ship-builders  half-models, row upon row of highly-detailed ship models in glass
cases, drawers  filled with priceless scrimshaw, ten foot long sperm whale
jawbones and more.  None of this is on public display. Bill led us out of the
climate-controlled  section, down a humid corridor, and then opened a door to
part of Mystic  Seaport's small craft collection --a grand hall filled with
hundreds of historic  boats of all shapes and sizes. Opening that door always
reminds me of the  closing scene in the movie "Raiders of the Lost Ark", a scene
where the camera  pulls back to display a hangar filled with hundreds of crates
containing untold  mysteries as far as the eye can see...

After the Collections  Research Center, we stopped by the G.W.Blunt-White
Library to have a peek at two  old logbooks, the log of the bark Reaper from
1809, and the log of the schooner  Weymouth (listed as the log of the "Indramayoe"
on the Seaport's web site). Both  of these logbooks contain worked lunar
distance observations, and I wanted  everyone to have a chance to see the "real
thing" --original early 19th century  lunar distance observations written out
long-hand-- with their own eyes. Next,  was my presentation on the basic history
of lunar distance observations  including a comparison of those logbook
calculations with an ordinary time sight  to demonstrate that the amount of
mathematical work involved, while a little  tedious, was by no means overwhelming.

Hebert Prinz's presentation  on Lacaille's contributions to early nautical
astronomy, later on Friday, was  fascinating, and the graphics that he assembled
to ilustrate it were  professional in quality. It was interesting to see how
much interest was created  by a graphical solution to the basic problem of
spherical trigonometry. We ran  out of time for the last part of Herbert's
presentation, and we may have to get  him to do it again in 2007. Friday evening,
half of us had an informal dinner at  a nice seafood restaurant with a view of
Fisher's Island Sound in Noank. It was  fascinating to hear how different
people had become interested in the topics of  navigation and navigational history.
One of our attendees was the author of a  history of the Blunt family, the
publishers of early editions of Bowditch's  Navigator. Another was formerly an
engineer at Harvard Observatory. Others were  interested in anything
navigational.

Saturday morning we were  prepared to shoot some lunar distances at
Stonington Point starting at 9am.  Alas, the Moon was visible only until about 8:45,
and then clouds moved in.  Instead we shot some horizontal angles, some Sun
altitudes, and generally had a  good time "messing around with sextants". The day
was predicted to be sparkling  clear, but by mid-day we had light showers.
Typically unreliable Connecticut  weather!

Saturday afternoon, Ian Jackson delivered a really  excellent presentation on
Scoresby's whaling voyages and the associated  navigational problems (and
George and Renee were present in spirit when he  showed the traverse board
illustration). Ian's a talented speaker. Our next  scheduled speaker, Trudy E. Bell
had to attend another conference (in New  Orleans, related to the history of
floods). Fortunately, one of our other  speakers, Craig Waff, was kind enough
to present her interesting paper on the  "American Method" of telegraphic
longitude determinations. It's interesting how  the history of electric longitude
determination is linked so closely with the  development of efficient recording
devices.

Also Saturday, I  presented the second part of my discussion of lunar
distance observations,  focusing on some of the calculational and technical details
and trying to bust  the myth that Bowditch's inventions with respect to lunars
were revolutionary.  Immediately after, Don Treworgy did a nice planetarium
program demonstrating  some of the tools that are available even in a
45-year-old planetarium for  teaching celestial navigation. In particular he took us to
polar latitudes to  see how low the Sun would fall on the North meridian
"below the pole" to  demonstrate the circumstances of finding latitude by midnight
Sun which Ian  Jackson had discussed earlier in the day.

Saturday night, our group  buffet dinner turned out very nicely. Ken Gebhart
was our dinner speaker, and  his tales of his navigational experience ferrying
planes across the Pacific and  starting and growing Celestaire were both
interesting from a business standpoint  and genuinely delightful as human
interest. It's great to hear little details  about air navigation, like recording
"dome error" by writing it at various  points on the inside of the canopy with a
marker. Myself, I was surprised to  learn how much Ken's business had grown
just within the past ten years. Ken, by  the way, won the longitude prize for the
Celestial Weekend, having traversed the  most meridians to reach Mystic. Ken
ended his talk with several challenges for  the future of celestial navigation
and celestial navigation education. In  particular, can we encourage and
foster a Boy Scout badge for celestial  navigation?

Sunday morning, we had another opportunity to shoot  lunars at Stonington
Point. The Moon was barely visible through high cirrus and  low-level haze. We
had more fun keeping track of the Moon visually as it moved  in and out of
clouds than actually taking sights. With such poor conditions,  it's not suprising
that our lunars were not very good. Almost everyone who  managed even one
lunar recorded a distance that was too long by anywhere between  1.5 and 3.0
minutes of arc. Since the limb of the Moon was so indistinct in the  haze, this
makes some sense.

Sunday afternoon, Craig Waff read his  own paper on the early debates over an
American prime meridian. He focused on  the people behind a "remonstrance", a
sort of petition signed by important men  in marine business of that era,
including J. Ingersoll Bowditch. Craig also had  many fascinating stories to tell
(over dinner) about the papers of Adams and the  discovery of Neptune, which
is his current area of research. Craig Waff, by the  way, is presently the
historian for the US Air Force's 89th Air Lift Wing, which  makes him the
official historian for "Air Force One".

Luis Soltero,  mathematician, software developer, and a highly experienced
sailor, delivered an  hour-long presentation on the development of his StarPilot
navigation software.  His philosophy for this product makes a lot of sense.
It runs on off-the-shelf  calculators (the excellent TI-89 is the current
platform) and provides the  navigator with the perfect celestial backup. He assumes
that very few navigators  will practice enough to be proficient with paper
tables (or even have them  onboard) when an emergency demands them, so he has
designed the StarPilot  software to be intuitive, easy-to-use, and completely
independent of other  sources of navigational information. There is also a PC
version which is  essentially an emulation of the calculator version. Luis has
created an  excellent sight planning tool for selecting twilight stars in
advance. He also  includes a simple tool for working lunars, but this is more of a
"just for fun"  tool without sufficient accuracy. The StarPilot software
includes a long-term  almanac, but I should say that I am skeptical of its accuracy
outside the twenty  year period from 1990 to 2010. That, of course, does not
diminish its practical  utility at all, and it's a great piece of work. It was
fascinating to learn  about it from the developer himself.

Or sextant workshop was an  opportunity to look at some interesting old
instruments from Don Treworgy's  personal collection, including an interesting
double-frame sextant and also a  very early Tamaya with an almost absurdly large
telescope attached. We also  experimented with a laser level, and I
demonstrated how to check for telescope  collimation (although it took a while to find an
instrument which was not  properly collimated!). Finally for the folks who
survived to the end, we had our  door-prize drawing: two framed pages of lunar
distances from the Nautical  Almanac of 1787. And one more seafood dinner down
in Noank by the marina with  thanks and handshakes all around finished it off.
Phew... What a busy week for  me. Maybe we'll do it again next year!

A final note:
Turn-out  for the whole event was at the low end of expectations. The total
number of  people who attended was only 20 with no more than 18 present at
once. This may  simply mean that we need to find another sponsoring venue. The
management of  Mystic Seaport apparently did nothing at all to publicize the
Celestial Weekend  except to note it in their members' newsletter.

-FER
42.0N  87.7W, or 41.4N 72.1W.
www.HistoricalAtlas.com/lunars

   

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