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

 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.


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.

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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. (

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

Originally posted on Quartz:

India has the highest number of enslaved people in the world.

More than 14 million out of India’s population of over 1.2 billion people are living in modern slavery, according to the second edition of the Global Slavery Index. Produced by an Australian human rights body, Walk Free Foundation, the survey defines modern slaves as those without individual liberty, by being subjugated to forced labor, trafficking and sexual exploitation.

An estimated 35.8 million people worldwide, or 0.5% of the world’s population, live as modern-day slaves.

In terms of the highest number of slaves as a percentage of a nation’s population, India is ranked fifth, with 1.14% of the country’s population trapped as slaves. The worst affected are people belonging to lower castes or tribes, religious minorities and migrant workers.

Of 167 countries surveyed, the worst 10 countries are home to 71% of the world’s slaves.


Government response

The Global Slavery Index gives…

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Middle East:A Misnomer?

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. 

Urban Dictionary: middle east.

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

Originally posted on The 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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From a Professor to a Showman: Kishen Pattnayak on Prannoy Roy

Originally posted on Kafila:

Translated from the original Hindi by Akhil Katyal

Kishen Pattnayak (1930-2004) was a socialist thinker and writer. He had been a member of the Indian parliament from Orissa. Pattanayak was the founding editor of a Hindi monthly periodical called ‘Samayik Varta’. In this Hindi essay ‘Professor Se Tamashgeer’ published in March, 1994, he understands Prannoy Roy as representative of a new class of intellectuals which came into being precisely with the changing economic policies of the Indian government in the early ’90s.

Those who do not know English in this country might not know Prannoy Roy. But knowing him is important because Prannoy Roy represents a new social phenomenon. Prannoy Roy’s fame has been sealed by the program “The World This Week” running every Friday on Doordarshan. Not unlike a magician putting on a show, it has lately become quite an art for Doordarshan to concentrate the attentions of the…

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Hiring a Forensic Accountant

Forensic accountants are an invaluable ally to attorneys in a number of situations. They examine and facilitate settlements to be more equitable and fair. While the need for a forensic accountant depends on a number of factors, there are some general cases in which they can be used. A forensic accountant can help arbitrate nasty situations and help mitigate disputes as well. Here are six situations in which a person will need to hire a forensic accountant.

1. Assess Commercial Damages

calcuForensic accountants are most commonly brought into a situation to provide expert witness regarding unjust enrichment or lost funds. This includes, but is not limited to, disputes over fraud, embezzlement, product liability, breach of contract, wrongful competition, and intellectual property infringement.

2. Settle Matrimonial Disputes


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Divorces never end well, and it can be useful to have a competent person divvying up the assets. Divorces and annulments oftentimes require a forensic accountant to trace, locate, and evaluate assets. It is paramount that the accountant ensures an equal division of funds and assets between the two parties involved. A forensic accountant may also determine how much money should be used to pay child support.

3. Uncover Hidden Income and Assets


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In the case of divorce, or suspected foul play by a partner, a forensic accountant may find transferred, deferred, or hidden income. The forensic accountant uses a combination of factors, including a party’s income to pay expenditures, net worth, and bank deposits.

4.Shareholders and Partnership Disputes/Employee Fraud  Investigations


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Forensic accountants are often called upon to analyze accounting records to trace and quantify the compensation, benefits, or distributions received by shareholders or owners or partners. This includes, but is not limited to, tracing funds, forensic intelligence gathering, suspect interviews, due diligence reviews, and asset identification and recovery.

5. Commercial Insurance Claims


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Forensic accountants may also be called on to assist with a commercial business claim. This includes business interruption, employee dishonesty (fidelity), and property loss claims. Forensic accountants carefully review a party’s financial situation to provide an accurate estimate of loss. This will help identify how much an entity can collect, and it is important to remember that the forensic accountant, in this respect, can be hired by either the insurance company or by the insured.

6. Personal Injury Claims


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In this particular case, a forensic accountant will be hired to analyze the injured party’s economic losses due to loss of salary or services. A similar set of analysis is required for cases of wrongful termination and medical malpractice. The report is usually given in a formal report or expert testimony.

Forensic accountants are relied upon in a wide variety of situations. Hiring the right accountant could mean the difference between saving thousands of dollars and being footed with a big bill. Make sure that your accountant is reputable, starting with proof that he or she completed a forensic accounting degree from a reputable university.

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