Is there something wrong with the list? It seems that Edley is responding to a message about a Dodwell dial, but I never received it.
Bill Gottesman Burlington, VT In a message dated 12/19/2001 4:41:11 AM Eastern Standard Time, [EMAIL PROTECTED] writes: > > Date: 12/19/2001 4:41:11 AM Eastern Standard Time > From: [EMAIL PROTECTED] (Edley) > Sender: [EMAIL PROTECTED] > To: [EMAIL PROTECTED] (Peter Mayer) > CC: [email protected] > > Hello Peter, > > Wow, The Dodwell dial is amazing! I wish I had some better pictures > so that I could see it in some more detail. The surfaces appear to > be of the "Astroid/Evolute of an Ellipse" type. I assume the > "unwinding of the analemma" is by multiple gnomons? This has given > me an idea for a different kind of polar dial that covers all the > hours. I've got to think about this one. I too am at a loss as to > how he made it in the 1940's! There were some cam fed machining > tools that could have done the basic curves of the design, but laying > out the actual hour lines must have taken a long time. > > Thanks much!, > > Edley McKnight >
