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 - 313 strani
 

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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 : * The experiments were made by the author.
Stran 43 - Castillo, and Dormentes, with a negro named Estevancio," arrived at Culiacan, on the gulf of California, from the peninsula of Florida. These were the sole survivors of the three hundred Spaniards who in 1527 landed with Pamfilo Narvaez on the coast of Florida with the intention of conquering that country. Nunez subsequently conducted the expedition which discovered the Rio de la Plata and effected the first conquest of Paraguay. Early Explorations — In 1542 Mendoza, Viceroy of Mexico, sent Rodriguez...
Stran 142 - Size, nine feet on top, six feet bottom, four feet deep. Grade from seven to eight feet to the mile. The greater part of the ditch is cut in granite, and in places there are solid walls, fifty to seventy feet high, built of stone.
Stran 225 - Travels, pp. 77-8. the blocks, and has given excellent results. The block and rock riffles are not desirable for those sluices which have frequently to be cleaned up. So far, experience shows square block riffles to be the best for saving gold. The objection to their use is the cost of wear and tear. Rocks are the most economical substitute, but sluices set with them require steeper grades and more water than those arranged with blocks. As a matter of convenience and economy, block riffles should...
Stran 105 - The stream feeding the reservoir has a maximum flow during great freshets of 5,000 to 7,000 cubic feet of water per second. The existence of other reservoirs higher up the stream adds to the danger from great floods, and therefore the Bowman dams have been designed to withstand not only freshets in the canons, but also any additional influx of water caused by the breaking of the upper dams.
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 163 - TV of an inch thicker than the iron of the pipe, and with a play of ^ 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 180 - FIG. 33. Their construction was very defective. The pressure of the water caused the joint to move hard, and when the pipe was turned horizontally it was apt to "buck," or fly around in a contrary direction.
Stran 73 - ... diffused throughout the detritus. Whilst working this claim a large hole in the bedrock twenty-five feet deep was bottomed. The hole was filled with gravel, but no pay was obtained. The pay stratum was found to be on a level with and a continuation of the pay stratum of the rest of the claim. On the other hand, at the Chesnau and French Hill Claims, whenever these hollows are found, a large yield of gold is invariably obtained. The experience of miners in the gold-fields of Victoria has led to...
Stran 240 - It is impossible to lay too much stress on the importance of the dump, as without it hydraulic mining could not be carried on.

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