Franz Ritter was a German mathematician and astronomer whose works are extremely rare. This beautiful engraving is a horological diagram remarkable for the elaborate decorative border. At top is a large cartouche and at bottom is a 32-point wind rose. A very rare and unusual cartographic curiosity.
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Condition: A+
A dark impression on a bright sheet with a small medallion watermark, issued folding and now flattened. Binding trims at left have been professionally replaced.