Franz Ritter was a German mathematician and astronomer whose works are very rare. This beautiful engraving is a horological diagram that includes depictions of the Zodiac. It is most remarkable for the elaborately engraved decorative border with a large cartouche and 32-point wind rose.
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Condition: A
A dark impression on a bright sheet with a small medallion watermark, issued folding and now flattened with a couple of printer's creases. Binding trims at left have been professionally replaced.