Hi Daniel you can revolve your horizontal sundial 3° around the polar axis and it will be ready to show the time of a place with a difference of 3° of longitude.
It may be difficult to do this rotation so you can change declination and inclination of the dial so the new orientation corresponds to the revolving. I don't know your latitude, if it was 45° (for example) you may revolve the dial of 2.12° around an axis (a line on the dial) which forms an angle of 1.06° with the meridian line. If you give me your latitude I can give you the correct angles (I use spheric trigonometry to calculate them). This revolving has the same origin useful to rearrange a dial in an other place. The new orientation must keep the same elevation angle of the polar axis, the dial has to be revolved of the difference of longitude and it will show the correct time (if the Sun illuminates the sundial with new orientation). One of the first picture I drew, some years ago, was a machine where an oriented dial may be revolved around the polar axis, the dial shows the time of another place with a difference of longitude like the revolving angle. ciao Fabio Fabio Savian fabio.sav...@nonvedolora.it Paderno Dugnano, Milan, Italy 45° 34' 10'' N 9° 10' 9'' E GMT +1 (DST +2)
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