Annual Report of the Isthmian Canal Commission ...

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U.S. Government Printing Office, 1908
 

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Página 74 - States may be necessary and convenient for the construction, maintenance, operation, sanitation and protection of the said Canal and railroad. All such works of sanitation, collection and disposition of sewage and distribution of water in the cities of Panama and Colon...
Página 74 - The Republic of Panama further grants to the United States in perpetuity the use, occupation and control of any other lands and waters outside of the zone above described which may be necessary and convenient for the construction, maintenance, operation, sanitation and protection of the said Canal or of any auxiliary canals or other works necessary and convenient for the construction, maintenance, operation and sanitation and protection of the said enterprise.
Página 175 - A rough estimate of the open space can be made from the uniformity coefficient. Sharp-grained materials having uniformity coefficients below 2, have nearly 45 per cent, open space as ordinarily packed; and sands having coefficients below 3, as they occur in the banks or artificially settled in water, will usually have 40 per cent. open space. With more mixed materials the closeness of packing increases, until, with a uniformity coefficient of 6 to 8, only 30 per cent, open space is obtained, and...
Página 196 - Schlichter0 says: If the particles of sand or gravel which make up the water-bearing medium are well rounded in form, the pores are somewhat triangular in cross section and the diameter of the individual pores is only one-fourth to one-seventh the diameter of the soil particles themselves. Thus if the individual grains of sand average one millimeter in diameter the pores through which the water must pass will average only one-fourth to one-seventh of a millimeter in diameter. If to a mass of nearly...
Página 174 - It was also found that in mixed materials containing particles of various sizes the water is forced to go around the larger particles and through the finer portions which occupy the intervening spaces, so that it is the finest portion which mainly determines the character of the sand for filtration.
Página 175 - This is conveniently shown by the "uniformity coefficient, " a term used to designate the ratio of the size of grain which has 60 per cent, of the sample finer than itself to the size which has 10 per cent, finer than itself.
Página 196 - Darton states that the rate of flow in the sands of the Dakota formation, from which the remarkable artesian wells of South Dakota draw their supply, does not exceed a mile or two a year.
Página 196 - A" is the quantity of water that is transmitted in unit time through a cylinder of the soil of unit length ;md unit cross section under unit difference in head at the ends.
Página 7 - ... were prepared showing the cost for each increase in width of 5 feet up to 125 feet, and the views of the Navy requested as to the width that should be adopted. In a memorandum dated October 29, 1907, the President of the General Board of the Navy submitted a memorandum stating it was their opinion that sound policy would dictate an increase to a clear width of 110 feet...
Página 196 - Sclichter has also shown that if two samples of the same sand are packed, one sample so that its porosity is 26 per cent, and the other sample so that its...

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