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Keywords from Image Description:
HeveliusQuadrant. Hevelius' Quadrant Hevelius' quadrant German subtitle says Peter Crger's large azimuthal quadrant completed by Hevel according to Hevel's Machina coelestis Scanned from Geschichte der Astron Messwerkzeuge by Repsold Rivi de BadJPEG PDold original upload log page de Quadrant Rivi bytes no Quadrant Machina