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alluvial alluvions amalgam amount auriferous banks bed-rock blast blocks bottom bucket Butte County California cement cent channel claim Coast Ranges construction cost Creek cross drifts cubic feet cubic yards deposits discharge district ditch estimated Eureka Lake feet deep feet high feet long feet per mile feet per second feet wide flume French Corral gold gold-fields grade Grange granite gravel head height Hill hundred feet Hurdy-gurdy hydraulic mining inches deep inches in diameter inches of water iron La Grange length lower main sluice material Milton miner's inches miners mountain Nevada County North Bloomfield nozzle Pelton Wheel pipe placed Placer County plank pounds powder precious metal pressure box quantity quicksilver Report reservoir riffles River rivets rocks sand shaft side Sierra Nevada sills slope Smartsville South stone streams thick timber tion Total tunnel undercurrents Valley velocity washed wheel width yield Yuba
الصفحة 3 - ME A Practical Treatise on Hydraulic Mining in California. With Description of the Use and Construction of Ditches, Flumes, Wrought-iron Pipes and Dams; Flow of Water on Heavy Grades, and its Applicability, under High Pressure, to Mining.
الصفحة 126 - Bloomfield inch can only be considered an assumed rough estimate of discharge in twenty-four hours for one miner's inch. The theoretical velocity, in feet per second, of a fluid flowing into the air, through openings in the bottoms or sides of a vessel or reservoir, the surface level of which is kept constantly at the same height, 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...
الصفحة 136 - All water-courses on the line of the ditch should be secured ; their supply partially counteracts the loss by evaporation, leakage, and absorption, and frequently furnishes an additional quantum of water during several months of the year. (5) At proper intervals waste-gates should be arranged so as to discharge the water, when necessary, without risk of damage to the ditch. In regions of heavy snow these waste-ways should be provided at intervals not greater than one-half a mile.
الصفحة 118 - ... would suffer, nor can it be conceived how a total destruction of the structure could occur. The dam might settle and its usefulness be temporarily impaired, but the only effect that could result in the event of a breach would be a return to the condition of affairs at present existing. As the waters are already charged to their fullest extent, no larger quantity of debris could be transported to a , greater distance in a single flood. The report of LieutCol. GH Mendell to the Secretary of War...
الصفحة 215 - Its size is to be determined by the requirements of the work, 4x4 feet or 5 x 9 feet in the clear, according to circumstances. Whilst raising from the tunnel due precaution should be taken against accidents arising from the rush of water, sand, and gravel, which is liable to occur when the bottom of a deposit is tapped. Where a shaft 5...
الصفحة 43 - ... Conqueror of Mexico. He was glad to escape with his life, and never crossed the line which marks our southern boundary . Here we may note a very remarkable event which happened in the same year that Cortez was making his fruitless attempt. Four persons, Alvar Nunez Cabeza de Vaca, Castillo, Dorantes, and a negro named Estevancio arrived at Culiacan on the Gulf of California from the peninsula of Florida. They were the sole survivors of three hundred Spaniards who landed with Pamfilo Narvaez on...
الصفحة 226 - ... 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.
الصفحة 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.
الصفحة 163 - ... 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.