Hi Peter, In both planes the width of the slots is changing. For each half hour we tried to get the line of light disappearnig from an hour line and at the same moment a new line appearing on the next hour line. We did some experiments but the final was determined with the help of construction in Autocad. Don't ask me how I did it so many years ago.
The gentleman with the beard is a self portrait of Bill as he demonstrates the principle of hour or shadow planes very clear. Best wishes, Fer. Fer J. de Vries De Zonnewijzerkring mailto:[EMAIL PROTECTED] http://www.de-zonnewijzerkring.nl Home mailto:[EMAIL PROTECTED] http://www.iae.nl/users/ferdv/index-fer.htm Eindhoven, Netherlands lat. 51:30 N long. 5:30 E ----- Original Message ----- From: "Peter Mayer" <[EMAIL PROTECTED]> To: "Fer J. de Vries" <[EMAIL PROTECTED]>; <sundial@rrz.uni-koeln.de> Sent: Sunday, November 21, 2004 11:57 PM Subject: Re: Fw: 'Wineglass' of Sonius > Hi Fer, > Thank you very much for your comments. I should have checked the > URL for Karl's page; I see now that I consulted it a bit over a year ago. > I have two questions, one sensible (I hope), the other quite > childish, which I hope you will forgive! > You noted "Because of the thickness of the two plates the slots > needed to be of different widths. This was the most difficult part of > the calculation". Here, I imagine, that the slots on the 'sun side' had > to be wider than those on the 'dial side'. Is the best width of the > slots something one determines by experiment, depending on the size of > the dial and the thickness of the blocks? > Secondly, your reference to the articles in the Compendium reminded > me of something quite silly. In Figure 7 of the first article there is > a drawing of a handsome gentleman with a beard looking at the shadow of > a string. As one does when one tries to imagine the face of a person > whose voice one hears on the radio, I have wondered, more than once, > whether there is any resemblance to Fer,or Mac or Bill...! > > warmest wishes, > > Peter > > > > -- > Peter Mayer > Politics Department > Adelaide University, AUSTRALIA 5005 > Ph : +61 8 8303 5606 > Fax : +61 8 8303 3446 > e-mail: [EMAIL PROTECTED] > > ----------------------------------------------------------- > This email message is intended only for the addressee(s) > and contains information which may be confidential and/or > copyright. If you are not the intended recipient please > do not read, save, forward, disclose, or copy the contents > of this email. If this email has been sent to you in error, > please notify the sender by reply email and delete this > email and any copies or links to this email completely and > immediately from your system. No representation is made > that this email is free of viruses. Virus scanning is > recommended and is the responsibility of the recipient. > > -
