What's New Under The Sun
Elements of Dialing Course - 2025
Monday, 15 September 2025 19:42
NASS is pleased to announce the upcoming fifth instance of Elements of Dialing, our introductory course about sundials, their history, and the science that makes them work. The free 12-lesson course, intended for those are new to sundialing, runs from 27 October 2025 until 26 April 2026. The course instructor is Robert Kellogg, NASS Vice President and Sundial Registrar. Bob will be...
Sun Queen of World War II
Thursday, 11 September 2025 23:11
A Hungarian born American scientist, Mária Telkes (1900-1995), was called "The Sun Queen" and among other honors, was postmousthly inducted into the National Inventors Hall of Fame. She lived to 95 and for most of her life developed solar power in a variety of forms.
Trained as a biophysicist, she worked for Westinghouse Electrical and Manufacturing Company in Pittsburgh, PA, where she...
2025 Conference -Ottawa
Thursday, 28 August 2025 23:25
The annual NASS Conference was held 7-10 August, 2025 in Ottawa. As usual, the conference began late Thursday afternoon with an introduction social and a "grab bag give away", taking your chances with tickets to win the bag's prize. Will Grant was the final winner of the Walton Double Planar Polar Sundial, but Paul Ulbrich beat the statistic odds and won this prize three times,...
Prosciutto di Portici Sundial's Owner
Tuesday, 10 June 2025 18:51
Prosciutto di Portici (Ham) Sundial
Photo: Getty Images
The Prosciutto di Portici Sundial, more often called the Portici Ham Sundial, dates from the first century somewhere between 8 BCE to 79 CE. This small silvered bronze dial was uncovered on 11 June, 1755 in the ruins of Herculaneum (current day Portici) in the "Villa of the Papyri", buried in...
Hamilton Dial Dedicated
Friday, 06 June 2025 21:01
Sundial dedication May 31, 2025. At left is Kathleen Stuckey Fox, with the City Proclamation presented by Mayor Pat Moeller and City Council on-lookers Carla Fiehrer and Susan Vaughn offering congratulations.
On May 31, 2025 at 1pm, the Hamilton, Ohio, sundial (NASS Sundial Registry #1109) was re-dedicated in Monument Park. Originally dedicated in 1941 to the...
Frans Maes Received a Royal Decoration
Monday, 24 March 2025 21:33
Several years ago Frans decided to write the course on sundials that included self assessment questions to force students not only to read the text, but to internalize the concepts. And a final submittal question "not necessarily a difficult question, but: no answer, no new lesson." Thus Frans Maes began writing lessons and sending them out to students.
NASS has now used his material to create...
Pros and Cons of Daylight Savings Time
Monday, 24 March 2025 15:37
In a 24 March 2025 article from the on-line Science Advisor (American Association for the Advancement of Science) Phie Jacobs summarizes the "great debate" of the yearly shift from standard time to daylight savings time. In January 2025 the US Senate introduced the Sunshine Protection Act to permanently have daylight savings time year round. Certainly 54% of Americans do not like the...
Native American Moon Alignment Ring
Friday, 21 March 2025 19:26
Perhaps the most famous alignment circle in the United States is the Cahokia Woodhenge near St. Louis constructed between 700-1400 CE by Cahokia Indigenous native Americans. But there were an estimated 10,000 other earthen mounds that once were scatter across the mid-west..
In an article from Atlas Obscura (https://www.atlasobscura.com/articles/octagon-earthworks-ohio) by Olivia Young on March...
Hamilton Dial under Restoration
Friday, 21 March 2025 18:37
The Hamilton dial is in the restorative care of Jarrett and Celene Hawkins (Hawkins & Hawkins Custom, LLC in Cincinnati Ohio https://www.studio-hawkins.com/) in preparation for the dial's dedication on Saturday, May 31, 2025.
The face of the Hamilton Grand Army of the Republic (GAR) sundial has been cleaned and bead-blasted showing the dial as it was cast 84 years ago. In the process,...
VSSC Space Museum gets Polar Sundial
Tuesday, 17 December 2024 23:47
In November 2024, a team consisting of members from SPL, TTDG and CMD of VSSC successfully designed and installed an accurate and fully functional sundial at the Rocket Garden of VSSC Space Museum, Thumba (8.53°N, 76.86°E). Following a space theme, the vertical gnomon is a 3-stage rocket that casts its daily and seasonal shadow on a dial face 1 1/2 meters by 1 meter. The the sundial face...
Historic Sundials of Andalusia
Saturday, 16 November 2024 00:07
Esteban Martínez Almirón has published a new book Historical Sundials: Forgotten Andalusian Treasures (Relojes de Sol Históricos Tesoros Andaluces Olvidados) In it he reviews over 400 sundials from the Andalucian region of southern Spain Originally to celebrate the 25th year of the website https://relojandalusi.org/
Esteban Martínez Almirón began showing his sundial drawings on the site....
Shelbyville Sundial
Wednesday, 13 November 2024 19:36
It isn't often that a sundial face is created before the gnomon is attached. In Shelbyville IN a large, circular art piece in the form of a sundial, was created at the Blue River Trailhead early in 2024. If they had chosen an analemmatic sundial, a walker of the trail could have simply stood on the appropriate date and used his or her own shadow to tell the local solar time. ...
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![]() "Analemmatic or Azimuthal Dial"
J.J. de LaLande 1784
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The Analemmatic Sundial SourceBook was first published in 2004, revised in 2014, and now is again available in digital form on CD or by download from the north American Sundial Society. What is it? It is a very comphrehensive reference to the origins, history, and modern evolution of the analemmatic sundial compiled and edited by Fred Sawyer III, President of NASS.
It started with J.L de Vaulezard publishing a small work of 15 pages in 1640 descibing the dial in vague terms, promising to reveal its construction later "if I see that the work has been well received by you...." Four years later de Vaulezard published his "Treatis of the origin, demonstration, construction and usage of the analemmatic dial". A decade later Samuel Foster published "Elliptical or Azimuthal Horologiography" further describing the analemmatic sundial. The SourceBook reprints a facsimile of this and three other of Foster's original works.
The Historical Period includes not only the works of de Vaulezard and Foster but works by Aubri, Tuttell, Richer, Parent, Bion, Lalande, Bedos de Celle, Lambert, Oberreit, Boutereau, Meikle, Perret, Peaucellier, Viala, Lisbonne, Gruey, Marchand, Roguet and Chomard. For over 250 years these authors provide the earliest proof of the analemmatic dial, the introduction of the Foster/Lambert, diametral, and Parent variations, as well as many important historical and theoretical discussions of the analemmatic dial and its properties.
Study of the analemmatic sundial had a revival at the turn of the 20th century and again beginning in 1986 with the publication of "Equator Projection Sundials" by de Rijk. Other articles include R.J. Vinck's "Times of Sunrise and Sunset on the Analemmatic Sundial" further descriptions of seasonal points by Bailey and Sonderegger. Vinck's "The Elliptical, Circular and Linear Dials" detailing of the mathematical foundation of a whole class of azimuthal sundials with examples of strange looking sundials by Sawyer, Olgesby, Gianni, Massé, Sassenburg, Sonderegger, and Rouxel.
Fred Sawyer III has a number of articles within the Analemmatic SourceBook, including "Of Analemmas, Mean Time and the Analemmatic Sundial", "Foster's Diametrical Sundial", and many more.
The Analemmatic Sundial SourceBook provides a rich historical and mathematical account of the Analemmatic Sundial and its modern derivatives. Order yours today by clicking here: NASS Publications Order Form
Open the "Read More" to see the detailed contents