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SUNDIALS
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MAKING

Shepherd's sundials from Pringles's pack

Making sundials from available materials is really a good task for pupils. We plan to publish most simple and interesting models suggested by pupils during sundials lessons. Here is a model of altitude sundial, known as Shepherd's sundials.

You'll need high pack from Pringles chips with a plastic lid for gnomon attachment. For the gnomon a wooden skewer may be used, but any stick of appropriate size is OK. Dial is printed on self-adhesive sheet of paper. We used Shadows program for calculating hour lines at Moscow's latitude.
We use А4 size of paper for the dial. Cylinder's height is 230 mm, diameter - 75 mm, thus, the choosen length for horizontal gnomon is 100 mm. You can find ready dial print here.
How gnomon can be attached to the lid? Here is the simpliest attachment we could think up. You are welcome to experiment at your own.
Our sundial looks like this. Once again: more fantasy - the better. For example, assuming Sun's height is varying throughout the year highly, it make sence to provide 2 gnomons of different length for summer and winter period each.
Final view on the 3d of May (gnomon is near "1-V" mark). Local Sun time was 3 pm (but at 9 am Sun was at the same height!). To get mean local time, we need to take into consideration a longitude correction (30 minutes for Moscow) and equation of time at May, 3 (about +3 minutes). So, civil mean time is about 15:27.