Report of Progress ...

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Board of Commissioners for the Second Geological Survey, 1883
35 vols. are atlases.
 

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Página 30 - Colonies in America, and to prevent the Erection of any Mill or other Engine for slitting or rolling of Iron, or any plating Forge to work with a Tilt Hammer, or any Furnace for making Steel in any of the said Colonies...
Página 197 - ... its average width at not less than eighteen inches. It is bounded by regular and well-defined, nearly parallel walls, the prevailing material of which is a coarse, soft granite, composed chiefly of white feldspar and quartz. " It would seem to be a pretty general fact that such of these veins as are confined entirely or...
Página 220 - Finally are to be mentioned the gravels of various recent periods which have been studied by Prof. Henry Carvill Lewis, first mentioned in some papers included in the published proceedings of the Mineralogical and Geological Section of the Academy of Natural Sciences of Philadelphia for 1877-1879, and soon to be fully described in his special Report on the Glacial Moraine in Pennsylvania (Z).
Página 197 - It would seem to be a pretty general fact, that such of these veins as are confined entirely or chiefly to the gneiss bear lead as their principal metal, whereas those which are included solely within the red shale are characterized by containing the ores of copper. But the zinc ores, viz : zinc-blende and calamine, prevail in greater or less proportions in both set of veins, existing, perhaps, in a rather larger relative amount in the copper-bearing lodes of the red shale.
Página ii - EB HARDEN, topographer, in charge of illustrations for reports, and general correspondence at head-quarters, 907 Walnut street, Philadelphia, to whom all business communications respecting the Work of the Survey should be addressed. Anthracite Survey. CA ASHBURNER, geologist, in charge of the Survey of the Anthracite coal fields ; address 907 Walnut street, Philadelphia.

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