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Keywords from Image Description:
Meyers Tunnelbau Englischer Vortrieb. de Englische Tunnelbauweise Sohlenstollen Firststollen Ausweitung fr den obern Teil der Kappe Strossen Aushub fr die Widerlager dazu den Artikel zeno org Tunnel in Meyers Groem KonversationsLexikon zeno org images Author PDMeyers History of mining Images from zeno org