Mining Magazine: Devoted to Mines, Mining Operations, Metallurgy & C1860 |
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Page 16
... complete fusion the contents of the chamber are allowed to run off into a basin on the outside . As it cools , a crust is formed on the surface , which contains to a large extent sulphurets of copper , lead , and the impurities . This ...
... complete fusion the contents of the chamber are allowed to run off into a basin on the outside . As it cools , a crust is formed on the surface , which contains to a large extent sulphurets of copper , lead , and the impurities . This ...
Page 19
... complete decomposition of the ore , and the amalga- mation , is generally effected in the warm season in the course of two or three weeks , in the cold season much longer . The mixture is then transferred to a tub or vat , where the ...
... complete decomposition of the ore , and the amalga- mation , is generally effected in the warm season in the course of two or three weeks , in the cold season much longer . The mixture is then transferred to a tub or vat , where the ...
Page 41
... completing its analysis , and adding some further remarks on its associations . This mineral occurs in minute crystals which are rarely as much as one - tenth of an inch in length ; they are rhombic ' prisms , but not very distinct ...
... completing its analysis , and adding some further remarks on its associations . This mineral occurs in minute crystals which are rarely as much as one - tenth of an inch in length ; they are rhombic ' prisms , but not very distinct ...
Page 78
... complete . The lot is traversed by one or more narrow veins bearing coarse gold , and it is proposed to mine , in part at least , by the aid of water under pressure - the Hydraulic method of Califor- nia . The Company have secured the ...
... complete . The lot is traversed by one or more narrow veins bearing coarse gold , and it is proposed to mine , in part at least , by the aid of water under pressure - the Hydraulic method of Califor- nia . The Company have secured the ...
Page 86
... complete account of the present state of metallurgy abroad . Almost every important process has been in a greater or less degree re- investigated by the author ; and all the experimental results which it has required many years to ...
... complete account of the present state of metallurgy abroad . Almost every important process has been in a greater or less degree re- investigated by the author ; and all the experimental results which it has required many years to ...
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Common terms and phrases
acid amount antimony appears Arizona arsenic assay average basin beds Bornite bottom calcination California carbonate cent chemical chloride coal collieries contain copper cost Cretaceous crevice crystals cupel Dahlonega decomposed decomposition deposits depth discovery district east Edward Hitchcock employed explorations extended extraction formation formed fossils furnace galena geological geologists gold heat Hill hundred feet inches iron Lake Superior lead limestone locality lode lower mass matts melting metal metamorphic miles mineral Mining Company mountains nearly observed obtained occur opening operation orthoclase ounces oxyd pig metal portion pounds precipitation present produced proportion pyrites quantity quartz region Report reverberatory furnace rich river roasting rock salt sandstone schists shaft shales silver slag smelting Sonora specimens steel strata sulphate sulphur sulphuret surface Survey temperature Tetradymite thickness tion tons tubs upper Valley vein vicinity Virginiatown washed yield zeolites zinc
Popular passages
Page 427 - ... and by that name may sue and be sued, plead and be impleaded, appear, prosecute and defend, in any court of law or equity...
Page 155 - On this difficult and mysterious subject a work will very shortly appear, by Mr. Charles Darwin, the result of twenty years of observation and experiments in Zoology, Botany, and Geology, by which he has been led to the conclusion, that those powers of nature which give rise to races and permanent varieties in animals and plants, are the same as those which, in much longer periods, produce species, and, in a still longer series...
Page 86 - Post 8vo. 8s. 6d. (FC) Principles of Athenian Architecture, and the Optical Refinements exhibited in the Construction of the Ancient Buildings at Athens, from a Survey. With 40 Plates. Folio. 61. 5s. PERCY'S (JOHN, MD) Metallurgy; or, the Art of Extracting Metals from their Ores and adapting them to various purposes of Manufacture.
Page 98 - Gash veins may cross the strata at any angle ; but are limited to one particular group of strata, and are peculiar to the unaltered sedimentary rocks. True veins are aggregations of mineral matter, accompanied by metalliferous ores, within a crevice or fissure which had its origin in some deepseated cause, and which may be presumed to extend for an indefinite distance downwards. True veins are almost universally admitted by geologists to have originated in
Page 370 - ... and that cold shortness resulted from the presence of a like quantity of phosphorus ; it therefore became necessary to remove those substances. Steam and pure hydrogen gas were tried with more or less success in the removal of sulphur, and various fluxes composed chiefly of silicates of the oxide of iron and manganese, were brought in contact with the fluid metal during the process, and the quantity of phosphorus was thereby reduced. Thus many months were consumed in laborious and expensive experiments;...
Page 252 - An adequate Amount of Ventilation shall be constantly produced at all Collieries to dilute and render harmless noxious Gases to such an Extent as that the working Places of the Pits and Levels of such Collieries shall under ordinary Circumstances be in a fit State for working : 2.
Page 153 - I have thus failed to obtain satisfactory evidence in favor of the remote origin assigned to the human fossils of Le Puy, I am fully prepared to corroborate the conclusions which have been recently laid before the Royal Society by Mr. Prestwich, in regard to the age of the flint implements associated in undisturbed gravel, in the North of France, with the bones of elephants at Abbeville and Amiens. These were first noticed at Abbeville, and their true geological position assigned to them by M. Boucher...
Page 154 - France — slow movements of upheaval and subsidence, deranging but not wholly displacing the course of the ancient rivers. Lastly, the disappearance of the elephant, rhinoceros, and other genera of quadrupeds now foreign to Europe, implies, in like manner, a vast lapse of ages, separating the era in which the fossil implements were framed, and that of the invasion of Gaul by the Romans.
Page 152 - Faleoner, of the Brixham Cave, must, I think, have prepared you to admit that scepticism in regard to the cave-evidence in favour of the antiquity of man had previously been pushed to an extreme.
Page 154 - ... level of the Somme, for the deposition of fine sediment including entire shells, both terrestrial and aquatic, and also for the denudation which the entire mass of stratified drift has undergone, portions having been swept away, so that what remains of it often terminates abruptly in old river-cliffs, besides being covered by a newer unstratified drift. To explain these changes I should infer considerable oscillations in the level of the land in that part of France— slow movements of upheaval...