Mining and Metallurgy: Published Monthly by the American Institute of Mining and Metallurgical Engineers, Issues 25-36

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American Institute of Mining and Metallurgical Engineers., 1909 - Mineral industries
 

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Page 3 - We are of opinion, further, that the constitutional power of the State to insist that its natural advantages shall remain unimpaired by its citizens is not dependent upon any nice estimate of the extent of present use or speculation as to future needs.
Page 17 - Engineers, the American Society of Mechanical Engineers, the American Institute of Electrical Engineers, and the American Institute of Chemical Engineers...
Page 39 - The transporting power of a current varies as the sixth power of the velocity. * * * If the velocity therefore be increased ten times, the transporting power is increased 1,000,000 times. A current running...
Page 385 - The principal loss or waste attending coal-mining operations is that represented by the quantity of coal necessarily left in the ground as pillars to support the roof. In some cases it is also necessary to leave a foot or...
Page 384 - ... periods. The result obtained by this method is that the easily accessible and available coal will be exhausted about the year 2027, and all coal by the middle of that century.
Page 497 - We recognize the waters as a primary resource, and we regard their use for domestic and municipal supply, irrigation, navigation, and power, as interrelated public uses, and properly subject to public control. We therefore favor the complete and concurrent development of the streams and their sources for every useful purpose to which they may be put.
Page 526 - Xernst in 1897, has resulted in the development and perfecting of the glower which is now embodied in the Nernst lamp. This glower is composed of a mixture of the rare earth oxides and is made in the form of a small rod or pencil of chalk-like material, having wire terminals at either end. When cold, the glower is an...
Page 408 - The Snake river's fine gold is finer than any natural placer gold I know of. It is high grade and worth $19.50 per ounce, but requires fully 1,500 colors to weigh one cent in value ; yet under a powerful microscope, each color is an individual nugget showing abrasion marks. These particles are often coated, touched or spotted with a crystalline white film of some foreign substance that looks like silica under the glass, and this is what makes it necessary to polish it in a grinding pan before it...
Page 1 - In considering the conservation of resources it should be held in mind that : (1) The present generation has the power and the right to use efficiently so much of these resources as it needs. (2) The nation's needs will not be curtailed; these needs will increase with the extent and diversity of its industries, and more rapidly than its population. (3) The men of this generation will not mine, extract, or use these resources in such manner as to entail continuous financial loss to themselves in order...
Page 495 - The paramount use should be that of water supply; next should follow navigation in humid regions and irrigation in arid regions. The development of power on the navigable and source streams should be kept subordinate to the primary and secondary uses of the waters; though other things equal, the development of power should be encouraged, not only to reduce the drain on other resources, but because properly designed reservoirs and power plants retard the run-off and so aid in the control of the streams...

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