Re: azimuth dial

[JOHN DAVIS]

I was intrigued by the description of the Richard Whitehead dial in the BSS Register so I'm glad that you are investigating it. Whitehead was apprenticed to my hero Henry Wynne, who's large double horizontal dials feature azimuth scales. The one at Wrest Park (Bedfordshire) has an azimuth scale divided down to one-eighth points, as well as to quarter degrees.The points are labelled, for example, SWbS.Slightly later dials of similar size (about 750mm diameter) by Wynne seem to make do with quarter points and half degrees. Most of the other information on the dials is astronomical, rather than nautical.

By coincidence, I am currently designing a dial for an Americal client which willinclude a central pin to show the azimuth of the sun, particularly at sunrise/sunset. In this case, the gnomon will be of the cantelevered or underslung type where the shadow is cast by the bottom edge of the gnomon. This leaves the centre of the dialplate clear for the scales.

I would be interested to see how Whitehead arranged his shadow pin for the azimuth scale. Do you think it was an actual pin rather than a plumb-bob or plummet?

Regards,

John
-Frank Evans [EMAIL PROTECTED] wrote:
Greetings Fellow Dialists,I am interested in a pedestal dial in the English Lake District. My interest is in the arrangement for finding the azimuth of the sun. The dial is by Richard Whitehead, dated 1688, and a central compass rose is divided into points, the points being further divided into one eighths i.e. better than 1.5 degrees. The gnomon is vertically drilled for a central shadow pin, which is missing.Does anyone have any information about shadow pins in sundials and are there other examples of dials centrally inscribed in points with the object of finding the sun's direction. And were points an essentially nautical feature?The dial was first listed in the BSS Sundial Register, No,  in Cumbria, by Robert Sylvester.Frank 55N 1W-- Frank Evans[EMAIL PROTECTED]-Dr J R
 DavisFlowton DialsN52d 08m: E1d 05m

Any references on making a universal ring dial?

[michael Alexander]

Hello,

  As the subject says, I am looking for any information of the making of
universal ring dials.   So far I've only been able to find links to buying
them or seeing collections of them.  I would prefer any free sources, but
books would be welcome suggestions as well (especially with ISBN)  I
participate in some renaissance festivals and instead of having afew of them
configured for the different areas it would be nice to have a single 'pocket
watch' that can be used anywhere.

  Also, is there a way to create a 'normal' sundail that is specific for a
location and time frame?  Such as the month of may in chicago, taking into
account the equation of time?

Thank you,
Michael Alexander


-