For those of you intending to be at the NASS conference in Montreal (Sept.
14-16): Note that the cost of registration increases as of August 1.  If you
have not yet registered, you can save yourself some money by doing it now!
Send in your registration and check today.

Scheduled speakers:

Roger Bailey                The History and Use of Armillary Spheres
"What is an armillary sphere? A model of the universe? An astronomical
instrument? A tool for navigation? A computer? A sundial? A symbol of
science and technology, knowledge and power? A device for casting
horoscopes? How was the armillary sphere used by astronomers from
Eratosthenes, Hipparchus and Ptolemy to Copernicus, Tycho, and Kepler to
measure, calculate and predict the positions of the sun, moon stars and
planets? Was it used by the Magi to understand the Star of Bethlehem? How is
it used in astronomy, celestial navigation and the design of sundials? What
is the connection with Prince Henry the Navigator, the Portuguese voyages of
discovery and Manueline architecture? Why does it appear so frequently in
paintings, sculpture and architecture? Why is the typical modern armillary
sphere a useless degraded corruption of the original instrument?

This presentation will answer these questions by tracing the history of the
armillary sphere from its origin by the ancient Greek and Babylonian
astronomers to its use through history as outlined above. You will discover
how to use the armillary sphere to determine not only where on earth you
are, the current date and time of day but when and where the sun sets.

André Bouchard            La Commission des Cadrans solaires du Québec
A presentation on the ongoing work of the Québec Sundial Society.  For the
last 8 years, the CCSQ has been alive and well. We will explore its
publications, its registry of sundials, its bulletin (LE GNOMONISTE), its
web site,  its implications in the development of gnomonics in Québec, and
its links with the dialists of the world.

André Bouchard            The fine collection of sundials at the Stewart
Museum of Montréal
The Stewart Museum tells the history of the discovery, exploration and
development of New France, Québec and Canada, and their close relations with
the civilizations of Western Europe, which gave their births on the
continent. The Museum put together different collections representative of
the 16th, 17th 18th and 19th centuries in the history of North America, as
well as all types of instruments in the development of European
civilizations following the discovery of America. Among them, there is a
small, but very rich, collection of ancient sundials.

My purpose is to discuss the relative importance of that collection for any
dialist, but especially for the members of the Québec Sundial Society (La
Commission des Cadrans solaires du Québec). They must realize that the
Stewart Museum has the most important collection of sundials among the
museums of Québec.

Following the development of sundials in European civilizations, the Museum
naturally collected scientific and technological objects that related to
that development. For the dialists of North America, or the simple lovers of
sundials, this collection of sundials of the Stewart Museum of Montréal
illustrates, with a rare taste, the history of gnomonics, the art of making
the sundials.  It represents a unique expression of the importance of France
and the French civilization of the 16th and the 17th centuries in this part
of the continent, in New France and along the Mississippi River. It gives
also an idea of the changes that occurred in the 18th century, when Quebec
became a British colony.  In a time when travel is easy and affordable, this
small collection of a museum in Montréal gives a taste of the collections of
sundials in other cities around the world. What a great adventure in
gnomonics for all of us!

Robert Felix                 SUNMASTER 2002 - a portable solar timer and
navigator for the northern and southern hemispheres
A discussion of the development, the function and the ideas behind a new
universal ring dial available from Robert's shop.

Nancy Frankel             Keene State College Sundial Commission
The subject of this presentation will be a Sundial sculpture commissioned by
Keene State College in New Hampshire.  This is an east-west meridian sundial
designed so that the shape of the sunlight shining through an opening at the
top marks the hours. It is 6' high, 5' long and 40" wide and is made of
Design Cast, a man-made stone. I will concentrate on the sundial as
sculpture, how the dialing was incorporated into the design, and the process
of making it, from initial proposal to the finished work. This would include
a description of the material used and my experience with it in past works.
A slide presentation will document all phases of construction and I have a
maquette of the Sundial which can be put on display.

Bill Gottesman             Setting Your Sundial To Read Solar, Standard, or
Daylight
Savings Time.  A high precision method of sundial alignment.
My talk will present a method for aligning a sundial by taking three time
readings over the course of a day, as well as the theory behind it. No
tedious formulas will be discussed, but rather I will focus on concepts and
graphics. This method, which I have not found described previously, enables
all "right ascension" sundials to be properly tilted and aligned for optimum
precision, even dials made for a different location, without needing to know
the longitude or latitude of the dial's design! Interestingly, this method
also partly compensates for errors of poor construction, such as a tilted
gnomon.

Bob Kellogg                 A New Generation of Digital Sundial
Over the last five years there have been a number of digital dial patents,
including those relying on nearly uniform grills.  A new generation of
vertically declining digital dials is outlined that is suitable for window
installation.  The interior view of the dial presents the local time in real
alphanumeric such as "12:30 PM", similar to the principles given in the 1997
Patent 5,596,553 by Bob Kellogg.  This new generation of digital dials is
based on shadow planes described so elegantly by Mac Oglesby, et. al.

Tom Kreyche               Projections of the Sphere for the Planispheric
Astrolabe and Double Horizontal Dial
The most remarkable aspect of sundial design is the attraction it holds for
people with a spectrum of interests--from art, history and architecture to
the sciences. My personal bias is towards instruments that expose the
workings of the cosmos. The best examples are the planispheric astrolabe and
its close cousin, the double horizontal sundial, because they illuminate
with a remarkable aesthetic appeal. The armillary sphere and spherical
astrolabes could be considered, but they are distinctly different types of
instruments and will not be discussed in this paper.

The planispheric astrolabe and double horizontal sundial have important
similarities--they are both observational devices, used for measuring
positions of astronomical bodies, and also computational devices for solving
astronomical problems. However, the astrolabe is more flexible and suited to
computation, while the double horizontal sundial is more specialized as an
observational instrument.

The essential concept behind the astrolabe and the double horizontal dial is
the representation of the three dimensional celestial sphere onto a planar
surface, and related to an observer's local position.  This representation,
called a projection, can take many forms. Some projections are known from
antiquity, hundreds are published and many more have yet to be developed.
Their applications vary widely-from historical interest to common use in
mapmaking to purely mathematical recreations.

Over the centuries, many papers have been written on astrolabe theory and
design. Many are confusing because terminology was developed before the
science was completely understood. And the graphical design techniques that
were employed are less relevant today.

This paper uses strict cartographic descriptions to present a general
background on projections, and an in-depth discussion of those used for the
planispheric astrolabe and double horizontal sundial. This knowledge is
essential to understanding the designs and applications of these
instruments, and is applicable to other sundial designs as well. The paper
also includes a discussion of computer based design techniques.

Tony Moss                    Before Your Very Eyes !
A practical introduction to the layout of a sundial using Adobe Illustrator
software.  Using a laptop and a video projector the elements of a typical
dial will be generated from scratch on screen with the various tools,
techniques and shortcuts explained.

Fred Sawyer                The Foster Point Dial - Time In A Perfect Round
This talk will introduce a new form of horizontal sundial whose hour points
are distributed evenly around the dial as though on a clock face.  Although
the form is new, the dial design follows directly from a little known scale
developed in the 17th century by Samuel Foster.

Fred Sawyer               ShadowCatchers
This talk will introduce NASS members to a new publishing project designed
to give them access to facsimile reproductions of a number of rare books on
dialing.

Fred Sawyer                A New Universal Altitude Sundial
Fred plans to introduce a form of universal altitude sundial based on Samuel
Foster's 'geometrical square'.

Sara Schechner            Savvy Travelers
How time finding tools served those on the move in the Renaissance.  A look
at pocket sundials and astronomical compendia, with their remarkable
components (including gazetteers, specialized hour scales, astrolabes,
quadrants, nocturnals, maps, and travel guides).

John Schilke                Oh, East is East and West is West..A Note On The
Prime Vertical
The prime vertical is that great circle which passes through the zenith and
nadir and the east and west points of the horizon.  It is thus orthogonal to
the meridian and to the horizon.  It has a few properties which make it
useful for the diallist: several terms of formulae in common use vanish,
simplifying calculations.  We present two methods of establishing the PV as
well as examples of dials for which a readily determined local east-west
line is even more convenient than the meridian.

The Sundial Tour
Our Saturday bus tour will go through Montreal, Laval, Longueuil and
Boucherville and will highlight an amazing 19 sundials (1 armillary, 3
equatorials, 9 horizontals, 5 verticals and 1 polyhedral).  At the
Planetarium of Montreal we will view an exhibit of an additional 24 sundials
from the Stewart Museum.  We will have lunch at the Restaurant Hélène de
Champlain on St. Helen Island, with a view of Mount Royal.


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