Re: Request for information about a type of altitude dial
* The benefit of an altitude dial is that it does need to be aligned with the polar axis. With that concept in mind then a latitude adjusted altitude dial is not feasible. However, if one gives up that benefit, and takes an altitude dial and then tilting it towards the pole, or away from it, in other words now aligning it with true north or true south, such that at the new latitude, the dial is aligned in space matching that alignment of its design latitude, then the altitude dial will work at the adjusted new latitude. I have had fun with doing this with the shepherd dial. Some interesting dial plates can be generated that one would assume could never possibly work when so adjusted. However, they do. I have a three page article on my web site, less than 1mb in size:- www.illustratingshadows.com/altDialLatitude.pdf Simon Simon Wheaton-Smith www.illustratingshadows.com Phoenix, Arizona, W112.1 N33.5 > > From: Steve Lelievre >To: David Bell >Cc: "sundial@uni-koeln.de" >Sent: Sunday, June 1, 2014 3:46 PM >Subject: Re: Request for information about a type of altitude dial > > >Dave, > >That's the point I'm struggling to understand. I'm assuming a chain is >used to suspend the dial in use, but wouldn't it adjust itself to bring >the centre of gravity back under the point of suspension - effectively >making it impossible to rotate the dial face? > >Steve > > > >On 01/06/2014 7:36 PM, David Bell wrote: >> I don't know the name, but I believe the moveable "attachment point" is >> where the hanging loop clamps to the dial plate. Moving that will rotate the >> dial and altitude scale relative to vertical. >> >> Dave >> >> Sent from my iPhone >> >>> On Jun 1, 2014, at 3:13 PM, Steve Lelievre >>> wrote: >>> >>> Hi folks, >>> >>> http://www.pinterest.com/pin/301178293801331061/ >>> >>> What type of dial is this; I realize it's a form of altitude dial, but is >>> there a specific name for it? >>> >>> The accompanying note states that the dial can be adjusted for latitude by >>> moving "the attachment point". I don't understand which part of the >>> mechanism does that. Can anyone explain it for me? >>> >>> Lastly, I'm appreciate references for articles or webpages that discuss >>> these dials - history and mathematics. >>> >>> Thanks, >>> Steve >>> >>> >>> >>> >>> >>> >>> >>> --- >>> https://lists.uni-koeln.de/mailman/listinfo/sundial >>> >> > >--- >https://lists.uni-koeln.de/mailman/listinfo/sundial > > > >--- https://lists.uni-koeln.de/mailman/listinfo/sundial
June Compendium
The June issue of The Compendium is out (or soon will be!). This issue includes an article by Jeffrey Kretsch: Sundials For Indicating Ultraviolet Exposure. One of the references Jeff cites at the end of his article was printed incorrectly. It should be: http://www.wunderground.com/resources/health/uvindex.asp Fred Sawyer --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Request for information about a type of altitude dial
The benefit of an altitude dial is that it does need to be aligned with the polar axis. With that concept in mind then a latitude adjusted altitude dial is not feasible. However, if one gives up that benefit, and takes an altitude dial and then tilting it towards the pole, or away from it, in other words now aligning it with true north or true south, then the altitude dial will work at the adjusted new latitude. I have had fun with doing this with the shepherd dial. Some interesting dial plates can be generated that one would assume could never possibly work when so adjusted. However, they do. Simon Simon Wheaton-Smith www.illustratingshadows.com Phoenix, Arizona, W112.1 N33.5 > > From: Bill Gottesman >To: Steve Lelievre >Cc: "sundial@uni-koeln.de" >Sent: Sunday, June 1, 2014 3:35 PM >Subject: Re: Request for information about a type of altitude dial > > > >Neat dial. I don't know what it is called, but I like it and it's clever >pinhole date aperture. I suspect the note about attachment point and latitude >is incorrect. I am not aware of any altitude dial that is adjustable for >latitude (and still be mathematically correct). If there are any, I do not >think this is one of them. -Bill > > > > > >On Sun, Jun 1, 2014 at 6:13 PM, Steve Lelievre > wrote: > >Hi folks, >> >>http://www.pinterest.com/pin/301178293801331061/ >> >>What type of dial is this; I realize it's a form of altitude dial, but is >>there a specific name for it? >> >>The accompanying note states that the dial can be adjusted for latitude by >>moving "the attachment point". I don't understand which part of the mechanism >>does that. Can anyone explain it for me? >> >>Lastly, I'm appreciate references for articles or webpages that discuss these >>dials - history and mathematics. >> >>Thanks, >>Steve >> >> >> >> >> >> >> >>--- >>https://lists.uni-koeln.de/mailman/listinfo/sundial >> >> > > >--- >https://lists.uni-koeln.de/mailman/listinfo/sundial > > > >--- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Request for information about a type of altitude dial
Dave, That's the point I'm struggling to understand. I'm assuming a chain is used to suspend the dial in use, but wouldn't it adjust itself to bring the centre of gravity back under the point of suspension - effectively making it impossible to rotate the dial face? Steve On 01/06/2014 7:36 PM, David Bell wrote: I don't know the name, but I believe the moveable "attachment point" is where the hanging loop clamps to the dial plate. Moving that will rotate the dial and altitude scale relative to vertical. Dave Sent from my iPhone On Jun 1, 2014, at 3:13 PM, Steve Lelievre wrote: Hi folks, http://www.pinterest.com/pin/301178293801331061/ What type of dial is this; I realize it's a form of altitude dial, but is there a specific name for it? The accompanying note states that the dial can be adjusted for latitude by moving "the attachment point". I don't understand which part of the mechanism does that. Can anyone explain it for me? Lastly, I'm appreciate references for articles or webpages that discuss these dials - history and mathematics. Thanks, Steve --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Request for information about a type of altitude dial
I don't know the name, but I believe the moveable "attachment point" is where the hanging loop clamps to the dial plate. Moving that will rotate the dial and altitude scale relative to vertical. Dave Sent from my iPhone > On Jun 1, 2014, at 3:13 PM, Steve Lelievre > wrote: > > Hi folks, > > http://www.pinterest.com/pin/301178293801331061/ > > What type of dial is this; I realize it's a form of altitude dial, but is > there a specific name for it? > > The accompanying note states that the dial can be adjusted for latitude by > moving "the attachment point". I don't understand which part of the mechanism > does that. Can anyone explain it for me? > > Lastly, I'm appreciate references for articles or webpages that discuss these > dials - history and mathematics. > > Thanks, > Steve > > > > > > > > --- > https://lists.uni-koeln.de/mailman/listinfo/sundial > --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: Request for information about a type of altitude dial
Neat dial. I don't know what it is called, but I like it and it's clever pinhole date aperture. I suspect the note about attachment point and latitude is incorrect. I am not aware of any altitude dial that is adjustable for latitude (and still be mathematically correct). If there are any, I do not think this is one of them. -Bill On Sun, Jun 1, 2014 at 6:13 PM, Steve Lelievre < steve.lelievre.can...@gmail.com> wrote: > Hi folks, > > http://www.pinterest.com/pin/301178293801331061/ > > What type of dial is this; I realize it's a form of altitude dial, but is > there a specific name for it? > > The accompanying note states that the dial can be adjusted for latitude by > moving "the attachment point". I don't understand which part of the > mechanism does that. Can anyone explain it for me? > > Lastly, I'm appreciate references for articles or webpages that discuss > these dials - history and mathematics. > > Thanks, > Steve > > > > > > > > --- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Request for information about a type of altitude dial
Hi folks, http://www.pinterest.com/pin/301178293801331061/ What type of dial is this; I realize it's a form of altitude dial, but is there a specific name for it? The accompanying note states that the dial can be adjusted for latitude by moving "the attachment point". I don't understand which part of the mechanism does that. Can anyone explain it for me? Lastly, I'm appreciate references for articles or webpages that discuss these dials - history and mathematics. Thanks, Steve --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Canon sundial
Dear Dialists! I want to make a sundial with a cannon. Have somebody declination about the cannon? Thank You! Geza idomes...@mcse.hu --- https://lists.uni-koeln.de/mailman/listinfo/sundial
