Silver and Gold: An Account of the Mining and Metallurgical Industries of the United States |
Dari dalam buku
Hasil 1-5 dari 89
Halaman 23
... tunnel nearly four miles in length , conduct it thence into the mining regions lying adjacent to Bear River and the north and mid- dle forks of the American and their several tributaries , bringing a por- tion of it on to San Francisco ...
... tunnel nearly four miles in length , conduct it thence into the mining regions lying adjacent to Bear River and the north and mid- dle forks of the American and their several tributaries , bringing a por- tion of it on to San Francisco ...
Halaman 41
... tunnels can be run in from one - half to one - sixth of the time required by hand - drill- ing , so that one of the greatest objections to this kind of mining ( the great length of time required to drive a long tunnel ) is obviated ...
... tunnels can be run in from one - half to one - sixth of the time required by hand - drill- ing , so that one of the greatest objections to this kind of mining ( the great length of time required to drive a long tunnel ) is obviated ...
Halaman 42
... tunnel 65 by 93 feet . This new method of using water - power in the tunnel has completely satisfied the miners that the year 1871 has been a year of progression in mining , and that the day is now close at hand when their tunnels can ...
... tunnel 65 by 93 feet . This new method of using water - power in the tunnel has completely satisfied the miners that the year 1871 has been a year of progression in mining , and that the day is now close at hand when their tunnels can ...
Halaman 44
... tunnel a tread - mill horse - power can be placed on one side of the track in the tunnel , and be moved in as the tunnel is driven forward . Where a steam- engine is at the surface , power can be taken from it to operate in the deepest ...
... tunnel a tread - mill horse - power can be placed on one side of the track in the tunnel , and be moved in as the tunnel is driven forward . Where a steam- engine is at the surface , power can be taken from it to operate in the deepest ...
Halaman 52
... tunnels run to strike the channel . From the best data at our disposal we estimate the total length of tunnels run in ... Tunnel Company , under the heading of " Tuolumne County . " Gravel deposits in the foothills . - The La Grange 52 ...
... tunnels run to strike the channel . From the best data at our disposal we estimate the total length of tunnels run in ... Tunnel Company , under the heading of " Tuolumne County . " Gravel deposits in the foothills . - The La Grange 52 ...
Edisi yang lain - Lihat semua
Istilah dan frasa umum
50 feet amalgam amount antimony arrastra assay average Bannack base bullion bed-rock bullion Calaveras County California CaƱon carbonate cent chemical claim coal commenced company's contains copper cost County course Creek Cupellation December deposits depth developed district ditch drift drill east El Dorado County engine erected Eureka expense extracted feet deep feet in length feet long feet wide furnace galena gangue gold Gold Hill gravel ground Gulch Hill hundred hydraulic inches incline iron labor lead ledge limestone located lode metallurgy metals miles mill miners Mining Company months nearly Nevada opened operations ounces owners placer mines pounds present Professor prospecting quantity quartz quartzite rich River rock San Francisco silver slag slate smelting smelting-works stamps stopes sulphurets sunk supply surface Table Mountain tailings thick tion tons Total tunnel Tuolumne County tuyeres Valley vein width yield