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Keywords from Image Description:
Tablica miernicza. pl Tablica miernicza Kopalni Rud Oowiu Fryderyk Tarnowskich Grach Zdjcie zrobione warszawskim Muzeum Techniki Tablice suyy kopalni jako punkty orientacyjne oraz stae punkty pomiarowe wyrobisk Tarnowskie Gry Poland Such boards were used in mines as landmarks and measurement points Picture taken in Warsaw Museum