Report on the Geology and Topography of a Portion of the Lake Superior Land District in the State of Michigan: Copper landsHouse of Reps, 1850 |
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Página 34
... continuous chains , but exist in groups , radiating from a common centre , presenting a series of knobs , rising one above another , until the summit - level is attained . Their outline is rounded or waving their slope gradual . The ...
... continuous chains , but exist in groups , radiating from a common centre , presenting a series of knobs , rising one above another , until the summit - level is attained . Their outline is rounded or waving their slope gradual . The ...
Página 58
... continuous lines of elevation ; while in others they appear to have flowed like lava - currents in sheets over the sands then in the progress of accumulation . The mineral substances which compose these ancient lavas are very various in ...
... continuous lines of elevation ; while in others they appear to have flowed like lava - currents in sheets over the sands then in the progress of accumulation . The mineral substances which compose these ancient lavas are very various in ...
Página 71
... continuous chains , but appears in rounded groups or isolated knobs . At the Algonquin mine ( section 36 , township 52 , range 35 ) the trap is rather compact , and much mixed with epidote . The ridge here bears northeast , and the ...
... continuous chains , but appears in rounded groups or isolated knobs . At the Algonquin mine ( section 36 , township 52 , range 35 ) the trap is rather compact , and much mixed with epidote . The ridge here bears northeast , and the ...
Página 77
... continuous ranges . The bed of the Presqu ' Isle was examined by us with great care , as well as the country lying west of the river , before the organization of the survey . The conglomerate is seen flanking the trap on the north , as ...
... continuous ranges . The bed of the Presqu ' Isle was examined by us with great care , as well as the country lying west of the river , before the organization of the survey . The conglomerate is seen flanking the trap on the north , as ...
Página 110
... continuous lines , but exhibit numerous projections and recessions . Peaks shoot up above the mass , like towers , connected by walls , which at the base are excavated into arches and gate- ways . The whole is crowned by a dense mass of ...
... continuous lines , but exhibit numerous projections and recessions . Peaks shoot up above the mass , like towers , connected by walls , which at the base are excavated into arches and gate- ways . The whole is crowned by a dense mass of ...
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Términos y frases comunes
adit afford amygdaloid appearance bands bearing north bedded trap belt bluffs boulders calc-spar Carp river chlorite clay cliffs coast compact trap Company composed conglomerate consists containing Copper Harbor crystalline depth distance drift deposites east elevation epidote excavated explorations extended fissures gangue geological granite greenstone Harbor height hills hornblende hundred feet igneous rocks inches intersect iron island Isle Royale Keweenaw Point lake shore Lake Superior limestone lode mass metal Michigan miles mineral mines Montreal river mountains native copper nearly northern northwest numerous observed occur Ontonagon river pebbles places Porcupine mountains porphyry Portage lake portion prehnite quarter of section quartz range 34 region ridge rises sand sandstone Saut seam seen shaft silver slope southeast southern southwest spar strata stratification stream striæ summit surface thickness tons township 58 traced trap range trappean rocks traversed vein veinstone vicinity width
Pasajes populares
Página 9 - The groves were God's first temples. Ere man learned To hew the shaft, and lay the architrave, And spread the roof above them — ere he framed The lofty vault, to gather and roll back The sound of anthems ; in the darkling wood, Amid the cool and silence, he knelt down, And offered to the Mightiest solemn thanks And supplication.
Página 149 - The rubbish taken from the mine is piled up in mounds, which can readily be distinguished from the former contour of the ground.
Página 209 - Fault, in the language of miners, is the sudden interruption of the continuity of strata in the same plane, accompanied by a crack or fissure varying in width from a mere line to several feet, which is generally filled with broken stone, clay, &c.
Página 7 - I have seen several such pieces in the hands of savages; and since they are very superstitious, they esteem them as divinities, or as presents given to them to promote their happiness by the gods who dwell beneath the water. For this reason they preserve these pieces of copper wrapped with their most precious articles.
Página 54 - The temperature of the water of Lake Superior, during the summer, a fathom or two below the surface, is but a few degrees above the freezing point. In the western portion the water is much colder than in the eastern — the surface flow becoming warmer as it advances toward the outlet.
Página 149 - He saw numerous evidences to convince him that this was an artificial excavation, and at a subsequent day, with the assistance of two or three men, proceeded to explore it. In clearing out the rubbish they found numerous stone hammers, showing plainly that they were the mining implements of a rude race. At the bottom of the excavation they found a vein with ragged projections of copper, which the ancient miners had not detached.
Página 119 - It is on the rivers, and the boatman may repose on his oars ; it is in highways, and begins to exert itself along the courses of land conveyance ; it is at the bottom of mines, -a thousand feet below the earth's surface ; it is in the mill, and in the workshops of the trades. It rows, it pumps, it excavates, it carries, it draws, it lifts, it hammers, it spins, it weaves, it prints.
Página 149 - The earth was so packed around the copper as to give it a firm support. The ancient miners had evidently raised it about five feet and then abandoned the work as too laborous. They had taken off every projecting point which was accessible, so that the exposed surface was smooth.
Página 120 - ... fortunate circumstance, not only to the company, but to the whole mining interest on Lake Superior. It gave encouragement to those engaged in these pursuits, and induced them to persevere. It also demonstrated the true source from which the loose masses occasionally found on the lake shore had been derived. It demolished the fanciful theory advanced by at least one geologist as to the transport of the...
Página 149 - When he had penetrated to the depth of eighteen feet, he came to a mass of native copper ten feet long, three feet wide, and nearly two feet thick, and weighing over six tons. On digging around it the mass was found to rest on billets of oak, supported by sleepers of the same material. This wood...