The theory and practice of hygiene (Notter and Firth) / by J. Lane Notter ... and W. H. Horrocks.
- James Lane-Notter
- Date:
- 1900
Licence: In copyright
Credit: The theory and practice of hygiene (Notter and Firth) / by J. Lane Notter ... and W. H. Horrocks. Source: Wellcome Collection.
Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.
114/1146 page 92
![iron salts present in the strata through which the weU is sunk, and also possibly to the reducing action of the iron pipes by which the water is ''''t^^^Z^:.:ters, however, come up to this standard : a ^ore ^^^^^^^^^^^ statement of a permissible limit would be that m cases ^-]^^\'}''^.'^^^^^^^ be excluded as the source from which a water derives J, f^l^' in nitrates and nitrites should not exceed 0-1 per 100,000. other cases, the nitrogen from nitrates alone ^^J^^'l^^ Z 100,000, or the total combined nitrogen (including that |J ^^^^ albuminoid ammonias) should in no case exceed 0-4 per ''O^O ^^^^^ third of a grain per gallon. On these points it is extremely difocult to hy down anTw anf-fast rules, as every individual sample of water needs Kludged'^pon its own analytical facts. The merest traces of nitr^e is always suspicion, and in most cases should condemn ^l^^J-^^'^^'' marked presence of nitrates ought to be ground for ^^^^^^J,f ^^ocess ^me soils especiaUy sands and gravels, and m ferruginous soils the p ooess rnttrScatioS goesL extremely rapidly, and ^1- —^^^^^^ hftetnSsr^rinicma.^^ the oxygen-consummg power of a;j^*^^J, also to g^^ige the character and organic matters, even if of the same ^^'J'^ ^^^J ^ne that is is, at best, only of accessory value. ^J^j7/;;;'^\,3,,/,f the oxidis- practicable for many medical officers, or gl'^^ ^^^^^ ,,,, knowledge, able organic matter in water and is ^ ? ^^^^^^ indispensable ^TttfIhl eoSit^^^ -ater, being to Frank- aid to our judgment of c<^ndition albuminoid ammonia lands carbon ^o^^lJ^^^^^^^ ^^iand has fully ackno.dedged this method IS to ^^^^^^ ^^JXand has proposed a series of factors by which to telation in his latest woik ^^^^ P,™^ the result in terms of organic multiply the oxygen absorbed so ^^^^^.^^^^ ^^^^^^^^^ the carbon. These factors are based on ^ne o ^^^^^^ two processes m a ^^^^nX ir average c^^^^^^ The factors differ for dividing the average carbon by the average uajq different kinds of water in the following proportions :- C River water, q 2-38 Deep-well water, m - Shallow-well water, ,, - ^ Upland surface water, - nvvnpn ahsotbetl indicates a probable amount of so that 1 eontlgramme of oxygen awo o i ^^^^^ ^ ^.j. only 1-8 of ?35trofo:ygen\llb:^^^ '](https://iiif.wellcomecollection.org/image/b2135764x_0114.jp2/full/800%2C/0/default.jpg)
