Sundials - In 'What to look for outside a church' - P J Hunt
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You will usually find sundials standing on a pedestal or column. The dial itself - in both sundials and scratch dials - is marked out in lines radiating from a central point and which represent hours, half-hours, and so on. In the centre is a metal rod, called gnomon or style, which casts a shadow onto the dial. When the sun is strong enough, you can tell the time by noting where the shadow falls on the dial. Some dials are puzzling, because they have marks where no shadow could ever rest.
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