Qanats: Underground Aqueducts- A reliable Source of Water in Arid Climate

Posted on November 21, 2014 by Rashid Faridi

 Qanat are series of well-like vertical shafts, connected by gently sloping tunnels. they create a reliable supply of water for human settlements and irrigation in hot, arid, and semi-arid climates.

 Persians started constructed elaborate tunnel systems called qanats for getting groundwater in the dry mountain basins of present-day Iran . Qanat tunnels were hand-dug, just large enough to fit the person doing the digging. Along the length of a qanat, which can be several kilometers, vertical shafts were sunk at intervals of 20 to 30 meters to remove excavated material and to provide ventilation and access for repairs. The main qanat tunnel sloped gently down from pre-mountainous alluvial fans to an outlet at a village. From there, canals would distribute water to fields for irrigation. These amazing structures allowed Persian farmers to succeed despite long dry periods when there was no surface water to be had. Many qanats are still in use stretching from China on the east to Morocco on the west, and even to the Americas.

Qanats are constructed as a series of well-like vertical shafts, connected by gently sloping tunnels. Qanats tap into subterranean water in a manner that efficiently delivers large quantities of water to the surface without need for pumping. The water drains by gravity, with the destination lower than the source, which is typically an upland aquifer. Qanats allow water to be transported over long distances in hot dry climates without loss of much of the water to evaporation.

Etymology

Qanats are also called kārīz (or kārēz from Persian: كاريز‎) (Iran, Afghanistan, Pakistan and Central Asia, derived from Persian: كاهریز‎), kahan (from Persian: کهن‎), kahriz/kəhriz(Azerbaijan); khettara (Morocco); galería (Spain); falaj (from Arabic: فلج‎) (United Arab Emirates and Oman); Kahn (Baloch) or foggara/fughara (North Africa).[8] Alternative terms for qanats in Asia and North Africa are kakuriz, chin-avulz, and mayun. Common variants of qanat in English include kanat, khanat, kunut, kona, konait, ghanat,ghundat.

In Urban systems

In some cities, water in qanats flows in tunnels beneath residential areas and surfaces near the cultivated area. Staircases from the surface reach down to these streams. The first access is usually at a public cistern where drinking water is available to the entire community. Sometimes these cisterns are sizable vaults as much as 10 meters across and 15 or more meters deep with spiral stairs leading down to small platforms at water level. In cities like Herat in Afghanistan, these cisterns are ancient constructions encased in tile. Other more modest urban access points are found along major streets, and even in some alleys, a factor that probably played an important role in the social and physical layout of the town.

Where tunnels run beneath houses, private access points provide water for various domestic uses. In wealthy homes, special rooms are constructed beside the underground stream with tall shafts reaching upward to windtowers above roof level. Air caught by the windtowers, which are oriented to prevailing summer winds, is forced down the shaft, circulates at water level, and provides a cool refuge from the afternoon heat of summer.

Qanats are build by a special group of masons called Mugannis in Iran and Karez Kan in Afghanistan. They inherit the skill of Qanat making from there forefathers.

read more here:

http://en.wikipedia.org/wiki/Qanat

http://www.waterhistory.org/histories/qanats/

Traditional Water Harvesting Systems of India

References

Afkhami, A., 1997, “Disease and Water Supply: The Case of Cholera in 19th Century Iran,” Proceedings of Conference: Transformations of Middle Eastern Natural Environments: Legacies and Lessons, Yale University, October.

Bahadori, M. N., 1978, “Passive Cooling Systems in Iranian Architecture,” Scientific American, February, pp.144-154.

Beekman, C. S., P. S. Weigand, and J. J. Pint, 1999, “Old World Irrigation Technology in a New World Context: Qanats in Spanish Colonial Western Mexico,” Antiquity 73(279): 440-446.

English, P., 1997, “Qanats and Lifeworlds in Iranian Plateau Villages,” Proceedings of the Conference: Transformation of Middle Eastern Natural Environment: Legacies and Lessons, Yale University, October.

Lightfoot, D., 2003, “Traditional Wells as Phreatic Barometers: A View from Qanats and Tube Wells in Developing Arid Lands,” Proceedings of the UCOWR Conference: Water Security in the 21st Century, Washington, DC, July.

Pazwash, N. 1983. “Iran’s Mode of Modernization: Greening the Desert, Deserting the Greenery,” Civil Engineering, March. pp. 48-51.

United Nationals Environmental Programme, 1983. Rain and Water Harvesting in Rural Area. Tycooly International Publishing Limited, Dublin, pp 84-88.

Wessels, K (2000), Renovating Qanats in a changing world, a case study in Syria, paper presented to the International Syposuim on Qanats, May 2000, Yazd, Iran.

Wulff, H.E., 1968, “The Qanats of Iran,” Scientific American, April, p. 94-105. (http://users.bart.nl/~leenders/txt/qanats.html)

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Why the world’s largest democracy has the most modern-day slaves

Posted on November 19, 2014 by Rashid Faridi
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Middle East:A Misnomer

Posted on November 17, 2014 by Rashid Faridi

A term which originated in the west to pack up a group of regions and nations which have different languages, history, and culture. People there do not think of themselves as “middle eastern”. They think of themselves as either Arabs, Turks, Persians …. and I can keep naming ethnicities for a long time. 

Another misconception is that what is called the middle east is mainly a desert. Most countries in the so-called middle east have only a limited desert area and others do not have deserts at all. 

The term ‘Middle East’ appears to have originated in the British India Office during the 1850s, inthe early days of expansionist rivalry between Russia and Britain. It became current in theEnglish-speaking world around 1900 when the American naval historian, A.T. Mahan, employedit in a discussion of British naval strategy in relation to Russian activity in Iran and a Germanproject for a Berlin to Baghdād railway.He was referring to a region centred on the Persian Gulf,for which the current terms ‘Near East’ and ‘Far East’ seemed inadequate. The term was alsotaken up by The Times correspondent in Tehrān V. Chirol, for a series of articles on the landsforming the western and northern approaches to India,2 the defence of which had been asensitive issue for more than a century and became more and more crucial as the strategic centreof the British Empire, no less than British trade, became centred upon the subcontinent . ‘Middle East’ was given respectability when it was used in the House of Lords on 22 March,1911 by Lord Curzon in opening a discussion of ‘the state of affairs in Persia, the Persian Gulf,and Turkey in Asia, in relation. . . to the construction of railways .

Clearly, the term ‘Middle East’ was one of strategic reference, developed in a Eurocentred world,just as the older terms ‘The East’, ‘Far East’ and ‘Near East’ had been. It was developed furtherduring the First World War when the operational theatre of the Mesopotamia ExpeditionaryForce came to be distinguished as ‘Middle East’ from the ‘Near East’ of Palestine and Syria inwhich the Egyptian Expeditionary Force operated.4 Although Curzon had already given the terma wider application than the lands centred about the Gulf, this only became permanent by aseries of accidents in military organization. In 1932 the existing Royal Air Force Middle EasternCommand, in Iraq, was amalgamated with Near Eastern Command, in Egypt, but the newcommand retained the title ‘Middle East’. When the Italian threat to the Suez Canal at thebeginning of the Second World War led to the establishment of a military headquarters in Cairo,the army followed the RAF in calling this ‘GHQ Middle East’. Between 1940 and 1943, the Cairoheadquarters controlled British and Allied operations over a very wide region . Theconstant use of ‘Middle East’ to describe this region in communiqués and amongst militarypersonnel made the term familiar to a large public. Continued political ferment in the region andits basic strategic importance have maintained the term in use, though not without some pleasfor the retention of the old term ‘Near East’.Indeed, the term ‘Middle East’ has become so useful that it is employed by the Russians and even the inhabitants of the region itself,though sometimes with reference to slightly different areas.

References:

Urban Dictionary: middle east.

THE MIDDLE EAST :A GEOGRAPHICAL STUDY

Peter Beaumont Professor of Geography, St. David’s University College, University of Wales

Gerald H. Blake Senior Lecturer in Geography, University of Durham

J. Malcolm Wagstaff Senior Lecturer in Geography, University of Southampton

David Fulton Publishers

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BOOK: The Age of Scientific Naturalism: Tyndall and His Contemporaries

Posted on November 15, 2014 by Rashid Faridi

darwinsbulldog's avatarThe Dispersal of Darwin

Pickering & Chatto has published as part of their Science and Culture in the Nineteenth Century series a collection of papers about the nineteenth-century Irish physicist John Tyndall, who wrote and lectured for the public, was a member of the X Club and Darwin supporter, and vocal critic of religion. Most of the papers are from a conference, held in Big Sky, Montana in June 2012, that brought together historians and students working on the John Tyndall Correspondence Project to present their research. I attended, and presented my MA paper. Unfortunately, for the publication, I did not have the resources necessary to do continued research for my paper. But I am happy to see the publication out, and delighted to see my paper in the book’s very first footnote. If anyone wishes to see my paper – “The ‘efficient defender of a fellow-scientific man’: John Tyndall, Darwin, and Preaching Pure…

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