A manual of jail hygiene for the use of medical subordinates / by W. J. Buchanan.

  • Buchanan, W. J.
Date:
1900
Catalogue details

Licence: In copyright

Credit: A manual of jail hygiene for the use of medical subordinates / by W. J. Buchanan. Source: Wellcome Collection.

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    water which is the source of the underground springs, which form either natural openings on the surface of the earth or are artificially tapped by man by means of wells. The sources of water-supply are very varied, but some of them do not concern us in considering the supplies to jails. They are as follows :— (1) Rain water (including snow). (2) Upland surface water. (3) Spring and well water. (4) River water. (5) Distilled water. (6) Sea water. Rain Water. This is the purest of all kinds of natural water. In its passage through the air it becomes highly aerated, but a the same time carries down with it any impurities which may be in the air, such as dust, smoke, etc. It is conse- quently cleaner in open country places than in large towns. It is collected in many ways—in India chiefly in the form of natm’al hollows or artificial tanks, or it may be collected from roofs of houses, etc., in cisterns. Rain water is very “ soft, ”* owing to comparative absence of salts of lime and magnesia; it is therefore good for washing and cooking purposes. Well and Spring Water. This water is naturally clear and bright in consequence of the filtration the water has undergone in its passa?e through the under-ground soil to reach the well. Wells are usually divided into shallow (subsoil) and deep.t Shallow wells are those under 100 feet deep. Deep wells are those over 100 feet in depth. A variety of deep Tor explanation see belo^v, page 38. be no such thing as a ‘ deep ’ well in the alluvial plains of Bengal ”-(5»7it).