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abundant Alaska amount appear average base basins beds blende bodies Bull carried cent character clay close concentration considerable contains County Creek crevices crystals deposits depth developed dike district dolomite Dubuque east evidence extending fact feet field flat formation Galena Geol Geology gold grains granite Hall important inches indicate Iowa iron irregular known later lead less limestone localities lower masses material miles mill mineral mines Mississippi nearly occur oil rock original oxide pitches places Platteville portion present probably production pyrite quadrangle quartz region relations represent result River Rochester shale sandstone schist seems seen sericite shaft shale showing shown side similar solutions species specimens streams structure sulphide surface Survey thickness thin upper usually Valley vein vertical walls Wisconsin zinc
Seite 36 - WS 158. Preliminary report on the geology and underground waters of the Roswell artesian area, New Mexico, by CA Fisher. 1906. 29 pp., 9 pis. PP 52.
Seite 126 - B 46. Nature and origin of deposits of phosphate of lime, by RAF Penrose, jr., with introduction by NS Shaler. 1888. 143pp. (Out of stock.) B 65. Stratigraphy of the bituminous coal field of Pennsylvania, Ohio, and West Virginia, by IC White.
Seite viii - The lead ore at these mines is now exclusively dug by the Fox Indians and, as is usual among savage tribes, the chief labor devolves upon the women. The old and superannuated men also partake in these labors, but the warriors and young men hold themselves above it. They employ the hoe, shovel, pickax, and crow-bar, in taking up the ore.
Seite 48 - This crevice was about two feet broad, the sides covered with mineral six to eight inches thick, leaving a space between the inner faces of the mineral up which we could see several feet. There was about this crevice an entirely new feature, so far as I know. The solid mineral projected from this crevice downward, a foot to a foot and a half in a * sheet...
Seite ix - About 1893 attention was again attracted to the soft-lead deposits of the Mississippi Valley, and a few years later the zinc ores of the region became properly appreciated. The most notable resultant contribution to the literature of the subject was the report on the lead a Senate Ex.
Seite 114 - ... prospect" in so barren a rock. According to this individual, the ore obtained here was all taken out "in the grass-roots" — ie, close to the surface — and no crevices had ever been found leading down to anything workable, a statement which agrees with all I have myself observed in the Lower Magnesian. On the whole, it will be safe to say that no profitable mining has ever been carried on in this rock, and that it is entirely wanting in well-developed crevices, or openings promising enough...
Seite 115 - The sheet of lead is cither imbedded in the crevice clay or fills the entire space between the rock walls. Where it extends south under the hill and has been little exposed to weathering agencies, the sides of the fissure have not undergone decomposition and the sheet is in contact with the rock. In other places where examined an inch or so of clay was found between it and the limestone, the crevice in this case being from 6 to 8 inches wide.
Seite viii - When a quantity of ore has been gotten out it is carried in baskets by the women to the banks of the Mississippi and then ferried over in canoes to the island, where it is purchased by the traders at the rate of $2 for 120 pounds, payable in goods.