Ok, I want to see if I have this. the declination lines are designed by laying out a series of circles at different diameters of degrees of arc. Where the circles intersect the hour lines determine the declination arc. When drawing the original dial, the Equinox line is determined as a basis of construction. So, the arc diameter of degrees is determined at the noon line.
The number of degrees from the equinox line, up and down, corresponds with the apparent height in the sky of the sun at noon and this determines date. This is how you can mark a particular date on any sundial and mark that as a line just as you would the equinox and solstices. So, where does one find the degrees to use for this measurement? I think I finally have the geometric construction figured out. Now I need to find the numbers for my degrees of movement from equinox. After this, I want to learn how to determine sunrise and sunsets with a dial. Of course, I live in mountains so, it really does not matter to me but I'd love to learn how it is done. Karon Adams Accredited Jewelry Professional (GIA) You can send a free Rosary to a soldier! www.facebook.com/MilitaryRosary www.YellowRibbonRosaries.com
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