This Sundials for Starters appeared in The Comendium in June 2010
by Robert Kellogg, Ph.D.
Some years ago I had the thrill of reading the Tiberius manuscript1, which in Old English presented a horologium, a set of shadow lengths, from somewhere in England. The shadow lengths were given throughout the year, such as on Christ’s Mass day where “the shadow at [mid] morning and nine [halfway through the afternoon] is twenty [less] a heel foot and at midday four and twenty.”
1 MS Cotton Tiberius A, iii – folio 179 o/v British Museum, Manuscript Library
This Sundials for Starters appeared in The Compendium in December 2013
Robert L. Kellogg, Ph.D.
Fig. 1 Analemma over the Acropolis photographed during the year by Ayiomamitis
As the shadows grow longer and we head for the winter solstice my mind turns again to the analemma, a concept invented by Grandjean de Fouchy in 1740 to describe the apparent irregular motion of the sun. Strictly speaking, this is the difference between the right ascension of the true sun minus the right ascension of the mean sun. While this is mathematically important to astronomers, it is esthetically pleasing that the apparent sun will describe a “figure 8” through annual motion in the sky. This “figure 8” or analemma is visible only when the sun’s position is compared to a “mean time” using a precise clock. The analemma (or the sun’s apparent East-West motion called the Equation of Time) allows us to answer the question “Will the time shown on my sundial be fast or slow compared with my watch?”
This Sundials for Starters appeared in The Compendium in March, 2006
by Robert L. Kellogg, Ph.D
I usually get up at 7am (ante meridian), but unlike ancient farmers, the time of rise has almost nothing to do with sunrise. One June 21st, and just west of Washington D.C. my sunrise occurs at 5:43 am Eastern Daylight Time (EDT). That would be 4:43 am Eastern Standard Time (EST) if we left our clocks alone. I’m almost due west of Washington D.C. and the Ellipse in front of the White House. Interestinglyu, my sunrise will occur about 44 seconds after sunlight rises on the White House. How does this relate to longitude?
At the 2014 NASS Conference in Indianapolis, Indiana, Fred Sawyer announced this year’s Sawyer Dialing Award is given to Robert Kellogg, “who, through his constant outreach, his unflagging support of NASS, and his technical ingenuity, as evidenced by his invention of the digital sundial, has helped to usher dialing into the modern age.”
Bob designed and patented a digital sundial based on sunbeam projection, first considered when he was at the US Naval Postgraduate School. But it took more than a decade for those ideas to gel into a firm technical form and a US Patent.
Bob continues to write “Sundials for Starters”, a regular column for NASS's Compendium. Over the last several years he has organized the joint NASS-Analemma Society outreach at the US Science and Engineering Festival and has brought sundialing to Montgomery County Schools in Maryland for the last 20 years.
Fred Sawyer presented Bob with an award certificate, the traditional cash prize of $200 and a custom made Spectra Sundial by Jim Tallman of Artisan Industrials.
[CHSI - Harvard Collection]
Appropriate to NASS’ visit, Harvard had just recently completed a new major exhibit entitled “Time and Time Again” offering conference members a unique view on the changes in time keeping and the social impact of timekeeping technology. On Friday afternoon, NASS members followed the Time Trails through the Harvard campus, locating historical sundials “in the wild” and timepieces in the Semitic, Peabody, and Natural History Museums.
The day was finished by two presentations “Trading in Time: European Pocket Sundials Designed for Colonial Use in American Territories by Sara Schechner and “Portable Sundials in Austrian Museums” by Ilse Fabian.
During Saturday a plethora of sundial talks were presented by NASS members, including “Counting the Sunny Hours” by Roger Bailey to a new “Wandering Gnomon Sundial Designn” by Fred Sawyer. Bob Kellogg presented the making of an animation illustrating the Ibn al-Shatir sundial proposed for Observatory Park in Virginia for the Analemma Society. One of the most color presentations was Art Paque’s update on Solargraphy, illustrating the technique of forming daily images of the sun a photographic paper that at the last is digitally scanned and preserved.
André Bouchard received the 2013 Sawyer Dialing prize at the Boston NASS Conference “In recognition of two decades of promoting, preserving, extending and exemplifying the pairimoine of Québecois of dialing and gnomonics.”
During the first 15 years of the CCSQ (la Commission des Cadrans solaires du Québec) André made numerous presentations on gnomonics, adopting objective and descriptive ways in order to highlight the specific elements of particular dials and dialist styles. Now as editor of The Gnomonist / Le Gnomoniste, André is rediscovering the fundamentals of philosophy through sundials, showing that they merge both in time, place, casting symbolic meaning and beauty within their surrounding. André illustrated this by discussing the design of the 2008 sundial on the shore of the St. Laurence River at Point aux Outardes Park near Baie-Comeau, where the polar gnomon and its supports simulate bull rushes, augmented by a flight of geese.
Fred Sawyer presented André with an award certificate, the traditional cash prize of $200 and a custom made Spectra Sundial by Jim Tallman of Artisan Industrials.
Read The Seattle Times article of May 14, 2013: http://seattletimes.com/html/localnews/2020985468_sundialxml.html
In the May 14, 2013 edition of The Seattle Times University of Washington professor Woody Sullivan was honored as ‘Mr. Sundial’ for his persistence in declaring Seattle as the Sundial Capital of North America. Dr. Sullivan has worked on more than a dozen dials in Seattle, including the large 20x30 foot vertical dial on southwest wall of the Physics and Astronomy building at UW and the elegant 11x17 foot reflection sundial painted on the ceiling of his garage at N 47° 41.232, W 122° 21.562. A small circular mirror outside the south facing window reflects a spot of light onto the ceiling.
The reflection sundial was a labor of love taking over 3 years to create. Woody marked over 700 locations on the ceiling that allowed him to draw the local solar time, dates, hours of daylight, solar azimuth and altitude, analemma, and even hours to dawn. And being a radio astronomer, he marked the transit sidereal time for two radio sources. The dial was painted with marvelous beauty by a local mural artist, Jim Noonan. The sundial is very personal to Woody, showing time marks for the date he married to the birthdays of himself, his wife, and two daughters. The zodiac painted along the ecliptic has a local touch, representing Pisces by a pair of sockeye; Cancer by a Dungeness crab; and Capricorn as a mountain goat. There is even a compass rose.
Fred Sawyer, president of the North American Sundial Society (NASS) is quoted by Erik Lacitis, Seattle Times staff reporter, saying “it’s likely true that Sullivan’s garage sundial is one of the best in North America.” When the NASS visited Seattle for the 2011 annual sundial conference, they visited Woody’s Reflection Dial and a marker was added to it for the date and time of itsofficial dial dedication held on Saturday 22 August 2011. “We toasted the sundial with an appropriate wine, ‘Wehlener Sonnenuhr’ by Joh. Hos. Prum, the fine Mosel Kabinett from the German vineyard with a large vertical sundial.” said Roger Bailey, the society’s secretary.
Among Dr. Sullivan’s accomplishments in the world of sundials began in the early 1990’s when the University of Washington’s Physics and Astronomy Building was being designed. He suggested a large vertical (southwest declining) sundial. The dial was completed in 1994 and Woody was hooked. He also helped design sundials used on the Mars exploration rovers Sprit and Opportunity that landed ion the Martian surface in 2004. A campaign to build sundials all around our world ensued with the motto “Two Worlds One Sun”. [photos from NASS]
Sundials for Starters
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Sawyer Dialing Prize
Fred Sawyer, in cooperation with the North American Sundial Society, established a continuing yearly award, the Sawyer Dialing Prize to be presented by NASS to an individual for accomplishments in or contributions to dialing and the dialing community.
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In these pages is the famous tub sundial created by Robert Terwilliger using his laser trigon to lay out hour lines on a very irregular surface to create a working sundial.
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Who are today's sundial artisans? Here are several bioghraphies of several artisans that show the unique combination of talents in art, engineering, and mathematics.
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