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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 <steve.lelievre.can...@gmail.com> >To: David Bell <db...@thebells.net> >Cc: "sundial@uni-koeln.de" <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 >>> <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 > > > >
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