Suggestions in regard to sanitary works required for improving Indian stations prepared by the Barrack and Hospital Improvement Commission. In accordance with letters from the Secretary of State for India in Council, dated 8th December 1863 and 20th May 1864.

  • Barrack and Hospital Improvement Commission.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: Suggestions in regard to sanitary works required for improving Indian stations prepared by the Barrack and Hospital Improvement Commission. In accordance with letters from the Secretary of State for India in Council, dated 8th December 1863 and 20th May 1864. 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.

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    Importance of meteoro- logy to drainage. Examina- tion and selection of water sources. 15 feet vertical above the land through which the outlet sewer is laid. All manholes are carried above the highest level of floods. Where lands desirable to be used for building purposes are water-logged by artficial constiuctions, it will be a question of removing the cause of obstruction or of arti- ficially draining the site proposed to be used. Pumping is resorted to for drainage purposes in many places, and will pay for purely agricultural uses. Sewage is pumped at West Ham. near London, and at Worthing, in England. The low levels of London will be pumped, as also the low levels at Bombay. The sewage pumps at West Ham are so arranged as only to lift to the actual head or level of the tide as each tide rises and falls, and not to a fixed extreme high-water head. Steam is the cheapest pumping power for large volumes of sewage of towns. For small volumes of sewage, proceeding from barracks or military stations, animal power may be made available; windmills cannot be depended upon, nor river currents, where weather and rain-fall are variable. In dealing with questions of drainage, it is important that the sanitary engineer should make himself acquainted with meteorology generally; and special attention should be paid to the meteorology of the district he is about to work in. There are many natural signs to be observed in a new country, indicating the meteoro- logical character of the district. If violent rain floods take place, steep ground will be furrowed, rocky ground will be bare, and watercourses and valley lines will show the violent effects of flood waters. In Great Britain, rivers rise in flood from low-water level some 20 feet; the river Eden at Carlisle, the river Ouse at York, and other rivers of a similar character. In South Africa, rivers rise 60 and 70 feet vertical in floods. In many parts of Europe, Spain, Italy, and other places, there is no water visible in dry seasons where roaring torrents come down occasionally. Many parts of India are similarly affected, as is known to Indian engineers. The engineer should ascertain to what extent extreme variations range. Mediums and averages only mislead, unless the full truth has been mastered and is comprehended. The seasons and years vary in Great Britain as much as one to two ; that is, at any point or place where a long average of years shows a mean rain-fall of 30 inches, then, during such period, it will be found that the driest year has been as low as 20 inches and the wettest year as high as 40 inches ; intermediate years oscillating between these extremes. All embankments, bridges, culverts, viaducts, or other water-ways must be suffi- cient for the largest possible flood that can take place. In Great Britain the dry weather volume in a river is increased by ordinary floods 300 times, and occasionally up to 500 times the dry weather volume. In tropical countries with heavy continued rains the excess will be much greater. In most parts of Great Britain the dry weather flow from land down streams and rivers is half a cubic foot per second from each 1,000 statute acres of land, and of course in ordinary floods this will be 150 cubic feet per second, and during extreme floods 250 cubic feet per second. It will be of the utmost importance, in dealing with questions of drainage and water supply, to ascertain and record all meteorological extremes. Section II.—Water Supply.* Every existing water-source, supplying a station or town, should be examined as to its available quantity, and also analysed by a competent chemist, to ascertain,— a. Its hardness, by Clarke's test. b. Nature of its constituents, suspended and dissolved. c. Quantities of each constituent per gallon. It is a first principle that water, containing suspended matter, should never be distri- buted in that state for the use of troops. The most important soluble ingredient in water is its organic matter. The amount of this should be very carefully estimated and its nature ascertained whether it be of animal or of vegetable origin. Any appreciable quantity of animal matter subject to putrescence is objectionable in tropical climates and in such climates as those of India. Water containing it should either be purified from its presence, or, if this cannot be done, it should be rejected altogether. A grain or two of vegetable matter per gallon is not so objectionable. * Recommendation of the Royal Commission respecting Water supply. 8. That all existing water sources be subjected to analysis, and those rejected which contain matters injurious to health. That the present method of drawing and distributing water be discontinued wherever practicable. That all water used for drinking purposes be filtered, or otherwise purified.