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Keywords from Image Description:
Meridiaanikone . en Meridian circle in the Meridian hall of the Helsinki observatory Made by Reichenbach und Ertel and Utzschneider und Fraunhofer ca fi Meridiaanikone Helsingin observatorion Meridiaanisalissa Reichenback und Ertelin ja Utzschneider und Fraunhoferin noin vuosina valmistama own MKFI Collections of the Helsinki