Franz Ritter was a German mathematician and astronomer whose works are extremely rare. This beautiful engraving is a horological diagram remarkable for the elaborately engraved 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
Tiny bit of faint foxing, still very good with a crisp impression and lovely color. Close bottom margin, as issued.