Recherche dans la collection - Coal mines in Spanish River. No. 1. Section of the coal- ground in the range of the main level and perpendicular to the horizon. No. 2. Section of the coal-ground, perpendicular to the horizon, in a direction tranverse to No. 1. No. 3. Plan of part of the coal stratum. With the whole of the Subterranean works. [cartographic material]

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