I agree with John and Jack, this dial is suffering from gnomon dysfunction. This affects a lot of older sundials. The intended gnomon was polar, not normal (perpendicular)..
Jack analyzed the hour lines and found that they are inconsistent. I did similar limited tests and agree. This sundial seems to be a mass produced brass plate item, not an engraved and gnomonically correct sundial. The patterns on the dial are easily mass produced as brass plate pressings. If this were the "Antique Road Show" I would not place a significant value on this sundial. Some things do not improve with age. Regards, Roger Bailey Walking Shadow Designs From: John Carmichael Sent: Monday, May 30, 2011 7:55 AM To: 'Sundial List' Cc: [email protected] Subject: FW: sundial /Jacopo de'Benci Hi Jan- I'm forwarding your letter and my comments to the Sundial List. Perhaps the sundial experts in our group can help you more than I can! _______________________________________________________________________________ Hello Dialists: I received this letter inquiring about an old European sundial. I'm not an expert on these things, so I'm forwarding the letter to you guys. I've never heard of the maker- Jacopo de' Benci whose name is inscribed on the dial. Looking at the enlarged photo of it at http://www.mediadesign.me/pollaiuolo/images/sonnenuhr-jacopo-de-benci-4.jpg you can see it has a perpendicular rod gnomon, implying that at first glance it is a nodus-based design. But the location of the rod seems to be incorrectly located at the convergence of the hour lines. I'm thinking that this dial was not designed to have a perpendicular gnomon. It should have an angled polar axis gnomon (an angled rod or a triangular sheet). Perhaps the rod was added to the original attachment hole after the original polar axis gnomon fell off at an earlier date. Does my analysis seem correct? Please copy your replies to Jan K. Botor at [email protected] Thx John C. From: info-mediadesign [mailto:[email protected]] Sent: Monday, May 30, 2011 2:45 AM To: [email protected] Subject: sundial /Jacopo de'Benci Dear Mr Carmichael. Mrs. Monika Leonhardt, M.A. (Uhrenmuseum Beyer Zürich) kindly provided me with your contact details. I am currently trying to investigate into the origin of this sundial and I kindly ask you for your opinion as an expert about this piece of applied art and your suggestion if it could possibly be authentic. My personal opinion is that it is a copy of something made in the 19th Century but I can not locate anything similar whether in books nor in the whole internet. I put the details that I know, a summary of suggestions I received 3rd hand and high-resolution pictures at the following link: http://www.mediadesign.me/pollaiuolo/index.html It is my intention to give it to an department for dendrochronical and spectroscopic analysis, as I got various information that differs widely regarding the possible age and origin. It is starting with suggestions, placing it around the early 19th century and goes as far as it was possibly an early work by Pollaiuolo at the goldsmith "Ghiberti" where Jacopo de' Benci was apprentice for Metalwork. That is well a wide range for speculations so, the coming analysis will place the object in a probable timeframe, I hope . I want to thank you in advance for your effort and It would be really nice to hear your opinion and if a scientific analysis would be advisable. If it is of interest, as the photographs are may not sufficient I would be glad to provide you with the original instrument for further research. With kind regards, Jan K. Botor Hauptstr.40 25704 Meldorf T 0178-7732125 [email protected] www.mediadesign.me -------------------------------------------------------------------------------- --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
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