Army manual of hygiene and sanitation, 1934 / [War Office].

Date:
1941
Catalogue details

Licence: Public Domain Mark

Credit: Army manual of hygiene and sanitation, 1934 / [War Office]. Source: Wellcome Collection.

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    An artesian well is a form of deep well which taps water under pressure, which therefore comes to the surface without Tube wells consist of lengths of iron tubing fitted together and driven into the ground. Deep springs deliver water from a deep water-bearing layer gases or minerals and therefore are sometimes used for medicinal purposes. Sources of water may therefore Be summarized as rain, and underground waters from springs, shallow wells and deep Impurities are found in all waters and are derived from the % pure, but it picks up dust, soot, germs and acids during its passage through the air. Streams and rivers pick up further im- products discharged into them and may therefore be heavily contaminated ; similarly ponds and lakes may be contaminated into the ground water dissolves salts and other substances from removed ; water, therefore, from a depth may contain many stances such as bacteria. Impurities in water may be in solution or in suspension. The impurities in solution consist of salts and chemicals which are dissolved in the water during its passage through the soil and, whless excessive in amount, they do not make the water unfit for drinking, although they may affect its uses ery clog boiler pipes by depositing the salts in them. Other salts The suspended impurities in water may be dead or living. Dead impurities may be decayed vegetable matter such as