A Practical Treatise on Hydraulic Mining in California: With Description of the Use and Construction of Ditches, Flumes, Wrought Iron Pipes, and Dams ...

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D. Van Nostrand, 1885 - 307 strani
 

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Stran 45 - No minerals of particular importance have yet been found in Upper California, nor any appearance of metals.
Stran 126 - ... is equal to that which a heavy body would acquire in falling through a space equal to the depth of the opening below the surface of the fluid, and is expressed as follows : In which z/=velocity in feet per second.
Stran 238 - When the cut is rapidly pushed ahead and the work not squared, the men at the pipes become encircled by the high walls and their lives are in danger. Where the banks exceed 150 feet in height, the deposit is usually worked in two benches. When the men at the pipes see that the bank is about to cave, the water should be immediately turned away, for if the cave falls on water, a rush of debris is liable to .follow, which may bury the pipes and force the men to run for their lives.
Stran 218 - ... is washed these are considered preferable on account of their cheapness. At Smartsville they have been found to serve fully as well as the blocks, and are claimed to be cheaper. It must, however, be stated that they are more costly to handle, as longer time is required to clean up and repave the sluices when they are used. In some sections of the State longitudinal riffles are preferred, ie, riffles made of scantling placed lengthwise in the sluice.
Stran 54 - Auriferous Gravels of the Sierra Nevada of California," which are the principal authorities for this chapter. the whole of the agricultural and the greater part of the mining districts. These lines divide the State geologically as well as physically. The Great Valley is the belt of recent alluvial deposits ; the Sierra is the belt of intrusive granite, of strata principally of triassic and Jurassic age, with important pliocene river deposits, of ante-cretaceous elevation, and of metamorphism induced...
Stran 45 - There is no doubt but that gold, silver, quicksilver, copper, lead, sulphur and coal mines, are to be found all over California, and it is equally doubtful whether, under their present owners, they will ever be worked.
Stran 124 - ... miner's inch of the Park Canal and Mining Company, in El Dorado County, discharges 1.39* cubic feet of water per minute. The inch of the South Yuba Canal Company...
Stran 125 - The size of the opening was taken with a measure (micrometer attached) which had been compared with and adjusted to a standard United States yard. Time was read to one-fifth of a second ; the level of the water (drawn from a large reservoir) was determined with Boyden's hook, micrometer adjustment The following results were obtained : One miner's inch will discharge in I second .026 cubic feet.
Stran 160 - ... of an inch between the inside of the collar and the outside of the pipe ; b is the lead, which is run in and then calked tight from both sides ; c is a nipple of No. 9 iron, 6 inches in width, riveted on one end of each pipe by means of six rivets.
Stran 46 - Fort, found some pieces of yellow metal, which he and the half dozen men working with him at the mill supposed to be gold. He felt confident that he had made a discovery of great importance, but he knew nothing of either chemistry or gold mining, so he could not prove the nature of the metal or tell how to obtain it in paying quantities.

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