John-- But isn't it saids that Babylonian and Italian hour-lines are straight lines?
Michael Ossipoff 2018-08-10 4:50 GMT-04:00 John Davis via sundial <sundial@uni-koeln.de>: > Diese Nachricht wurde eingewickelt um DMARC-kompatibel zu sein. Die > eigentliche Nachricht steht dadurch in einem Anhang. > > This message was wrapped to be DMARC compliant. The actual message > text is therefore in an attachment. > > ---------- Forwarded message ---------- > From: John Davis <john.davi...@btopenworld.com> > To: Dan-George Uza <cerculdest...@gmail.com>, Sundial List < > sundial@uni-koeln.de> > Cc: > Bcc: > Date: Fri, 10 Aug 2018 08:50:00 +0000 (UTC) > Subject: Re: Dyptich sundial - help! > Hi Dan, > > This is a fairly typical diptych dial, probably 17th century. Museums such > as the Whipple in Cambridge have large collections. It would probably be > possible to date yours more accurately by careful comparisons. > > The string gnomon for the horizontal dial is fixed to the wrong point - it > should come from the intersection of the hour lines on the horizontal dial. > > The two scaphe dials normally show Italian and Babylonian hours. > > The windrose on the outer surface is for showing wind direction. The small > hole in the panel allows the compass needle to be observed when the dial is > closed. The counter-changed rule is not original, I believe, and is an > inappropriate replacement. There should be a small vertical windvane which > would fit in the centre of the rose. > > I hope this helps. > > Regards, > > John > ------------------- > > Dr J Davis > Flowton Dials http://www.flowton-dials.co.uk/ > BSS Editor http://sundialsoc.org.uk/publications/the-bss-bulletin/ > <http://www.sundialsoc.org.uk/bulletin.php> > > > > ------------------------------ > *From:* Dan-George Uza <cerculdest...@gmail.com> > *To:* Sundial List <sundial@uni-koeln.de> > *Sent:* Friday, 10 August 2018, 9:23 > *Subject:* Dyptich sundial - help! > > Dear all, > > I've recently found this piece in a museum near me and I need your help in > dating it. > > Why are the hour marks offset? I suspect a correction for latitude. And > what do the two small circular dials on the bottom measure? > > Also what would be the purpose of the circular shape containing the > alidade? I suspect it has something to do with the winds. > > Any info will be highly appreciated. > > Thank you, > > Dan Uza > > > > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > > > > --------------------------------------------------- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > >
--------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial