Re: a unique sundial on a cylindrical column of opal glass
The article Un cadran solaire insolite sur colonne dans l'ancien couvent de la Baumette by Manuel Pizarro Gavilán was published in Le Gnomoniste in Dec 2010 and is available here: http://cadrans-solaires.scg.ulaval.ca/v08-08-04/quidnovi/XVII-4-p12-20.pdf This excellent article was also published in the SAF 'Cadrans Info in October 2010. Dials like these are often called top hat or filter sundials in English and filterhut in Austrian. Regards, Roger Bailey -- From: Helmut Sonderegger (Tele2) h.sondereg...@utanet.at Sent: Sunday, October 20, 2013 1:19 AM To: f.w.m...@rug.nl Cc: sundial@uni-koeln.de Subject: Re: a unique sundial on a cylindrical column of opal glass Dear Frans, here a photo of such a Filterhut dial with vertical slits around the edge. This sundial was found some years ago by Manuel Pizarro Gavilan on a column in the couvent of La Baumette near Angers (France). Time is read where the shadow of such a single stick is shortest i.e. vertically down. On Valentin Hristov's website you find constructions where this edge outside the cylinder is turned inside (with concetric hole in the circle plane on the top of the cylinder): http://www.mysundial.ca/tsp/deltacad_sundial_macros_vh_cylinder2.html. And in these versions finally one can get Willy Lender's beautiful sundial. Best wishes Helmut Am 16.10.2013 21:09, schrieb Frans W. Maes: Dear Helmut all, You are right, Willy Sullivan's sundial is not a shepherd dial. It is very similar to a so-called Filterhut dial; I am sure you know the type. For those who don't: that's understandable, as only a handful of examples exist. Attached is a picture of a specimen at the abbey of St. Martin-de-Boscherville (near Rouen in northern France). The time is read at the highest point of the ring's shadow edge. According to René Rohr, this type was described already by Athanasius Kircher in the 17th century. The accuracy is sometines increased by vertical slits around the edge, which makes it easier to find the sun's azimuth. Rohr continues to tell that the Arab scientist Abul Hassan al Marrakushi described already in 1272 a version in which only a small radial strip of the ring was present. Which exactly matches Sullivan's dial! Best regards, Frans Maes --- https://lists.uni-koeln.de/mailman/listinfo/sundial - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4158 / Virus Database: 3614/6765 - Release Date: 10/19/13 - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4158 / Virus Database: 3614/6765 - Release Date: 10/19/13 --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: a unique sundial on a cylindrical column of opal glass
Dear Helmut all, I don't think Woody Sullivan's sundial is very similar to Willy Leenders' impressive sundial. From a typological point of view, Sullivan's sundial is a shepherd dial. It uses the altitude of the sun to show the time. Willy Leenders' dial is a nodal dial, similar to a scaphe dial or a chalice dial. It derives the time from the sun's hour angle. Best regards, Frans Maes On 14-10-2013 15:17, Helmut Sonderegger (Tele2) wrote: Hi Roderick, I like Willys new sundial too. It looks beautifully. I included this sundial construction a longer time ago in my software SONNE and discussed different cylinder sundials in Compendium vol 16 nr. 4 (Dec 2009). In my freeware Sonne.exe you can construct the sundial for the outside of a cylinder with fixed orientation and moveable horizontal gnomon (see image below). Now Willy has positioned the Gnomon in the central axis of the cylinder and so the gnomon length is equal the radius and nee not be turned around. The construction stays the same but the scale is positioned on the Northern part of the vertical cylinder instead of South. By the way: Woody Sulllivan made a very similar construction on the outer side of a cone ( http://sundials.org/index.php/component/sundials/onedial/746 ) Helmut Sonderegger www.helson.at --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: a unique sundial on a cylindrical column of opal glass
Hi Larry, That's interesting in that you did a Sundial Patent. I’ve often wonder if it is worth it to Patent things as the cost could be high. I hope you don’t mind me asking, did you make any money and did it make you rich? I’ve downloaded your paten into my “Make Sundial” folder. Has the Patent expired? Are we now allowed to build it? Thanks, regards, Roderick Wall. From: Larry Bohlayer Sent: Tuesday, October 15, 2013 12:39 AM To: sundial@uni-koeln.de I patented a version of this type of sundial in the early 1980s and made a number of them (of smaller scale) in brass and glass. I coined the name “SunVial” to describe our product. More at: https://www.google.com/patents/US4384408?pg=PA1dq=bohlayerhl=ensa=Xei=iPJbUr_TJKigyAHWpIGwBQved=0CEoQ6AEwAw Larry Larry Bohlayer Celestial Products 608 Coral Bells Ct NW Concord, NC 28027-8034 540-338-4040 Fax 704-973-7799 la...@celestialproducts.com www.celestialproducts.com From: sundial [mailto:sundial-boun...@uni-koeln.de] On Behalf Of Helmut Sonderegger (Tele2) Sent: Monday, October 14, 2013 9:17 AM To: sundial@uni-koeln.de Subject: Re: a unique sundial on a cylindrical column of opal glass Hi Roderick, I like Willys new sundial too. It looks beautifully. I included this sundial construction a longer time ago in my software SONNE and discussed different cylinder sundials in Compendium vol 16 nr. 4 (Dec 2009). In my freeware Sonne.exe you can construct the sundial for the outside of a cylinder with fixed orientation and moveable horizontal gnomon (see image below). Now Willy has positioned the Gnomon in the central axis of the cylinder and so the gnomon length is equal the radius and nee not be turned around. The construction stays the same but the scale is positioned on the Northern part of the vertical cylinder instead of South. By the way: Woody Sulllivan made a very similar construction on the outer side of a cone ( http://sundials.org/index.php/component/sundials/onedial/746 ) Helmut Sonderegger www.helson.at Am 14.10.2013 06:16, schrieb rodwall1...@gmail.com: Hi Willy, That’s a great idea, thanks for showing us. Maybe someone will include it in their Sundial Software? Roderick Wall. From: Willy Leenders Sent: Monday, October 14, 2013 5:36 AM To: Sundial sundiallist Dear sundialists, I calculated a unique sundial on a cylindrical column of opal glass. It is inaugurated in the vicinity of Brussels (Belgium). The shadow of the sphere falls on the inside of the cylinder and can be seen through the opalescent glass on the outside. There the shadow gives an indication of the time and the date. You can see more information specially translated for you in English on my website on page http://www.wijzerweb.be/humbeek001AENGLISH.html Willy Leenders Hasselt in Flanders (Belgium) Visit my website about the sundials in the province of Limburg (Flanders) with a section 'worth knowing about sundials' (mostly in Dutch): http://www.wijzerweb.be --- https://lists.uni-koeln.de/mailman/listinfo/sundial--- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: a unique sundial on a cylindrical column of opal glass
Hi Helmut, Ok about Willy’s sundial. I need to install SONNE onto my new Laptop compute and see what it can do, thanks. I did have SONNE on my old computer. Willy’s sundial is interesting, maybe make one from a drinking glass and paint the hour lines using hobby glass paint. Regard, Roderick Wall. From: Helmut Sonderegger (Tele2) Sent: Tuesday, October 15, 2013 12:17 AM To: sundial@uni-koeln.de Hi Roderick, I like Willys new sundial too. It looks beautifully. I included this sundial construction a longer time ago in my software SONNE and discussed different cylinder sundials in Compendium vol 16 nr. 4 (Dec 2009). In my freeware Sonne.exe you can construct the sundial for the outside of a cylinder with fixed orientation and moveable horizontal gnomon (see image below). Now Willy has positioned the Gnomon in the central axis of the cylinder and so the gnomon length is equal the radius and nee not be turned around. The construction stays the same but the scale is positioned on the Northern part of the vertical cylinder instead of South. By the way: Woody Sulllivan made a very similar construction on the outer side of a cone ( http://sundials.org/index.php/component/sundials/onedial/746 ) Helmut Sonderegger www.helson.at Am 14.10.2013 06:16, schrieb rodwall1...@gmail.com: Hi Willy, That’s a great idea, thanks for showing us. Maybe someone will include it in their Sundial Software? Roderick Wall. From: Willy Leenders Sent: Monday, October 14, 2013 5:36 AM To: Sundial sundiallist Dear sundialists, I calculated a unique sundial on a cylindrical column of opal glass. It is inaugurated in the vicinity of Brussels (Belgium). The shadow of the sphere falls on the inside of the cylinder and can be seen through the opalescent glass on the outside. There the shadow gives an indication of the time and the date. You can see more information specially translated for you in English on my website on page http://www.wijzerweb.be/humbeek001AENGLISH.html Willy Leenders Hasselt in Flanders (Belgium) Visit my website about the sundials in the province of Limburg (Flanders) with a section 'worth knowing about sundials' (mostly in Dutch): http://www.wijzerweb.be --- https://lists.uni-koeln.de/mailman/listinfo/sundial--- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: a unique sundial on a cylindrical column of opal glass
Dear Willy, Beautiful work! Thank you for sharing this with us. best wishes, Peter On 14/10/2013 5:06 AM, Willy Leenders wrote: Dear sundialists, I calculated a unique sundial on a cylindrical column of opal glass. It is inaugurated in the vicinity of Brussels (Belgium). The shadow of the sphere falls on the inside of the cylinder and can be seen through the opalescent glass on the outside. There the shadow gives an indication of the time and the date. You can see more information specially translated for you in English on my website on page http://www.wijzerweb.be/humbeek001AENGLISH.html Willy Leenders Hasselt in Flanders (Belgium) Visit my website about the sundials in the province of Limburg (Flanders) with a section 'worth knowing about sundials' (mostly in Dutch): http://www.wijzerweb.be --- https://lists.uni-koeln.de/mailman/listinfo/sundial -- Peter Mayer Discipline of Politics International Studies (POLIS) School of History Politics http://www.arts.adelaide.edu.au/historypolitics/ The University of Adelaide, AUSTRALIA 5005 Ph : +61 8 8313 5609 Fax : +61 8 8313 3443 e-mail: peter.ma...@adelaide.edu.au CRICOS Provider Number 00123M --- This email message is intended only for the addressee(s) and contains information that may be confidential and/or copyright. If you are not the intended recipient please notify the sender by reply email and immediately delete this email. Use, disclosure or reproduction of this email by anyone other than the intended recipient(s) is strictly prohibited. No representation is made that this email or any attachments are free of viruses. Virus scanning is recommended and is the responsibility of the recipient. --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: a unique sundial on a cylindrical column of opal glass
Hi Willy, That’s a great idea, thanks for showing us. Maybe someone will include it in their Sundial Software? Roderick Wall. From: Willy Leenders Sent: Monday, October 14, 2013 5:36 AM To: Sundial sundiallist Dear sundialists, I calculated a unique sundial on a cylindrical column of opal glass. It is inaugurated in the vicinity of Brussels (Belgium). The shadow of the sphere falls on the inside of the cylinder and can be seen through the opalescent glass on the outside. There the shadow gives an indication of the time and the date. You can see more information specially translated for you in English on my website on page http://www.wijzerweb.be/humbeek001AENGLISH.html Willy Leenders Hasselt in Flanders (Belgium) Visit my website about the sundials in the province of Limburg (Flanders) with a section 'worth knowing about sundials' (mostly in Dutch): http://www.wijzerweb.beinline: humbeek001A.jpg--- https://lists.uni-koeln.de/mailman/listinfo/sundial
