Water and Water Supply

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D. Van Nostrand, 1890 - 144 páginas
 

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Página 40 - Here is what I am referring to, and I think it is one of the most important things, if not the most important thing, with which this Committee has to deal. That is, whether or not, when the Federal Government grants a patent, which is an exclusive right to use an idea, there ought to be some agreement under which the patentee could not refuse the granting of the right to use to anybody who paid a reasonable compensation...
Página 120 - It will be safe to infer, however, from the above results, that there is no river in the United Kingdom long enough to effect the destruction of sewage by oxidation.
Página 119 - Thus, whether we examine the organic pollution of a river at different points of its flow, or the rate of disappearance of the organic matter of sewage when the latter is mixed with fresh water and violently agitated in contact with air, or finally the rate at which dissolved oxygen disappears in water polluted with 5 per cent, of sewage, we are led in each case to the inevitable conclusion that the oxidation of the organic matter in sewage proceeds with extreme slowness...
Página 119 - ... we are led in each case to the inevitable conclusion that the oxidation of the organic matter in sewage proceeds with extreme slowness even when the sewage is mixed with a large volume of unpolluted water, and that it is impossible to say how far such water must flow before the sewage matter becomes thoroughly oxidized.
Página 119 - It is evident, that so far from sewage mixed with twenty times its volume of water being oxidized during a flow of ten or twelve miles, scarcely two-thirds of it would be sO destroyed in a flow of 168 miles at the rate of one mile per hour, or after the lapse of a week.
Página 118 - ... feet of air. The results indicated approximately the effect of oxidation which would be produced by the flow of a stream containing 10 per cent, of sewage for 96 and 192 miles respectively, at the rate of one mile per hour.
Página 121 - ... produce an injurious effect upon health. Therefore, if a large proportion of organic matter was removed by the process of oxidation, the quantity left might be quite sufficient to be injurious to health. With regard to the oxidation, we know that to destroy organic' matter the most powerful oxidizing agents are required ; we must boil it with nitric acid and chloric acid and the most perfect chemical agents. To think to get rid of organic matter by exposure to the air for a short time is absurd...
Página 33 - ... in town districts, even a few miles distant from a town, is not a pure water for drinking ; and that if it could be got direct from the clouds in large quantities, we must still resort to collecting it on the ground in order to get it pure. The impurities of rain are completely removed by filtration through the soil...
Página 90 - ... compression. This fact convinced him, that pipes in that position were very insecure. Commonly, in similar cases, there was a pressure of water on the inside, and a pressure of earth on the outside; and it was a usual arrangement for the valve which shut off the water to be placed under the embankment...
Página 122 - it ought to be made an absolute condition for a public water supply that it should be uncontaminable by drainage.

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