Rod:
Here are photos of actual clocks for sale with spiral faces. Notice that the hour numerals in each turn of the spiral are radially aligned so that the clock hands point to the same numerals in all the turns. A planar equatorial dial would be the perfect dial type to use in this design. See : http://www.cafepress.com/+spiral+clocks The dial you referred to was invented by Bill Gottesman and it takes the form of a 3D helix. regards From: rodwall1...@gmail.com [mailto:rodwall1...@gmail.com] Sent: Friday, June 23, 2017 2:36 PM To: John Carmichael; sundial@uni-koeln.de Subject: Re: Golden Ratio and Sundials Hi all and thanks to everyone who responded to my questions. All very interesting. John I have never see a spiral clock face. Very interesting thanks. Learn something every day. That had me thinking. I think I have seen somewhere where there is a spiral sundial. Where a spot of light marked the time on the numbers on the spiral. Wonder if it was a Golden Ratio spiral. Have fun, Roderick Wall. ----- Reply message ----- From: "John Carmichael" <jlcarmich...@comcast.net> To: "'rodwall1...@gmail.com'" <rodwall1...@gmail.com>, <sundial@uni-koeln.de> Subject: Golden Ratio and Sundials Date: Sat, Jun 24, 2017 2:34 AM Rod: Do a goggle image search on “spiral clock face”. A similar sundial face design could be made. Time marks and numerals could be adjusted to be in the proper positions to be a functional sundial. From: sundial [mailto:sundial-boun...@uni-koeln.de] On Behalf Of rodwall1...@gmail.com Sent: Wednesday, June 21, 2017 2:04 PM To: sundial@uni-koeln.de Subject: Golden Ratio and Sundials Hi all, I have been reading a book on the Golden Ratio which is 1.6180339887. It describes how the Golden Ratio describes how the spiral of a sea shell is produced. And how nature uses the Golden Ratio on the size of leaves etc. Does anyone know if sundials have ever been produced useing the Golden Ratio. The Golden Ratio goes back in history so one wonders if it was ever applied to sundials. The book describes that the short and long sizes of credit cards are close to being the Golden Ratio. LongSide/ShortSide = Golden Ratio. Regards, Roderick Wall.
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