RV: Seasonal Sunrise Marker

[Martha A. Villegas]

You can see two examples of  analemmatic sundials with these marks, at the Frans Maes page:   http://www.biol.rug.nl/maes/zonnewijzers/en/slyk-ewyk-e.htm   http://www.biol.rug.nl/maes/zonnewijzers/en/ootmarsum-e.htm   ...and also a link with a very good math page related with this. See:   http://pass.maths.org/issue11/features/sundials/   Greetings,   Martha A. Villegas   25°32' N 103° 27' W