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The Persian wheel is a mechanical water lifting device operated usually by draught animals like bullocks, buffaloes or camels. It is used to lift water from water sources typically open wells. In Sanskrit the word Araghatta has been used in the ancient texts to describe the Persian Wheel. The ‘ara-ghatta’ comes from the combination of the words ‘ara’ meaning spoke and ‘ghatta’ meaning pot.
There is evidence to argue that this system of lifting water from open wells was probably invented in the India of the past. With its use also in Iran, the then Persia, and perhaps its discovery there, it came to be called the Persian wheel. The celebrated writer philosopher Ananda K Coomaraswamy in his monograph ‘The Persian Wheel’ argues that it is not justified to draw its origins to Persia as it finds mention in the Panchatantra (3rd Century BCE) and the Rajatarangini (12 th century CE) as the ‘cakka-vattakka’ or the ‘ghati yantra’.
The word ‘araghatta’ itself became to be called the rahat or reghat in North India, a name by which it is known even now. The Araghattikka or arahattiyanara describes the person or animal working the Araghatta and this description was extensively used in the twelfth century. Usually men, bullocks, elephants or camels did the job of moving in circles to lift water.
Noria or the Saqia?
The biggest confusion amongst authors and people is between the more common water wheel and the Persian wheel. The water wheel -the noria- is perhaps an Egyptian invention and is a stream or river based water lifting device. It even acts as a water mill at times. It is however powered by water and not by draught animals. It uses the strength of the water current to move and to translate that to a grinding action in the case of a mill and to lift it to greater heads in other cases.
The Persian wheel, also the saqia, is a land based water lifting device from wells, more in the nature of a pump. In fact in parts of Kolar in Karnataka, India it is called a ‘bucket pump’. It does not use water power but draught animal power to lift water from open wells. Joseph Needham, in Science and Civilisation in China, Vol. IV(2), gave a clear definition of the two forms, the noria having the containers fixed to the rim of the wheel, and the saqiya on the rope or chain flung over the wheel (p. 356).
Lifting height, operation and efficiency
The Persian wheel usually operates to a maximum depth of 20 metres beyond which the weight of the pots becomes too much for the oxen to lift.
The FAO document on water lifting devices is an excellent one to compare the efficiencies of various lifting devices for water.
As it states- “The Persian wheel, is a great improvement on the ‘mohte’ [a water lifting device using a leather bucket and a rope to pull up water usually by a draught animal], as its chain of buckets imposes an almost constant load on the drive shaft to the wheel. Persian wheels are usually driven by some form of right angle drive. The first is the most common, where the drive shaft from the secondary gear is buried and the animals walk over it; this has the advantage of keeping the Persian wheel as low as possible to minimize the head through which water is lifted. The second example is a traditional wooden Persian wheel mechanism where the animal passes under the horizontal shaft. The sweep of a Persian wheel carries an almost constant load and therefore the animal can establish a steady comfortable pace and needs little supervision.”
“Although Persian wheels (…) are mechanically quite efficient, the main source of loss from these types of device is that some water is spilled from the buckets and also there is a certain amount of friction drag caused when the buckets scoop up water, which again reduces efficiency. Also, the Persian wheel is obliged to lift the water at least 1 m (or more) higher than necessary before discharging it into a trough, which can significantly increase the pumping head, particularly in the case of low lifts. The traditional wooden Persian wheels also inevitably need to be quite large in diameter to accommodate a large enough collection trough to catch most of the water spilling from the pots; this in turn requires a large well diameter which increases the cost.”
Ancien usage of the Persian wheel
Ubiquitous everywhere in India, as were open wells, the Persian Wheel’s use was widespread in the ninth and tenth century particularly in Rajasthan. As late as 1920 there were 600 Persian Wheels introduced by the then collector Brayne in Haryana alone.
The typical fort in ancient India was perched on a hillock or a rocky citadel. Water harvesting was common but also the Persian wheel was common to lift water from lakes below up through several steps to the top of the fort itself. Golconda fort near Hyderabad in Andhra Pradesh state and Jodhpur fort in the state of Rajasthan are but two examples of forts where the Persian wheel was used to obtain water from wells. Even here the systems have been removed and now it cannot be seen as to how the ancients used the system. In Pedgaon of Ahmednagar district of Maharashtra a large Persian wheel brought water to the fort and the township from the river Bhima till the 1850’s.
Present usage of the Persian wheel
The Persian wheel still exists in some parts of India especially in parts of Southern and Eastern Rajasthan, the state of Jharkhand and in the Indo-Gangetic plain where the groundwater aquifers are still shallow. In typically poorer parts of India, where electricity has not reached as yet and where endowment is considerable, Persian wheels are still in use. The state of Jharkhand in Eastern India is an example. Here many parts of the district do not yet have electricity. Diesel is prohibitively expensive and hence pumps cannot be used. The Persian wheel continues to be the main lifting device for water. In Pakistan, Persian wheels continue to operate in the provinces of Punjab and Sind lifting water from open wells.
Elsewhere, as ground water levels decline in India, Persian wheels cannot reach the water to draw them out from open wells. Many such Persian wheels stands forlorn and abandoned as the water table has dipped in places such as Kolar, Karnataka. Wheels which have worked for the last 80 years are being sold as scrap. The last factory which made Persian wheels closed in the year 1982.
The Persian Wheel is perhaps actually the Indian Wheel. The ‘ara-ghatta’ was a leap in the hydraulics of agriculture and represented technological progress in the voluminous use of water. Extensive irrigation must have become possible through the use of animal power and this technological development would have helped extend irrigation to larger tracts of land.
But falling water tables have made the Persian wheel redundant as well as the arrival of the electric pumps, their greater yield and cost efficiencies.
However, the Persian wheel represents a water culture and water heritage of India. It therefore seems imperative to document and preserve the knowledge base around this instrument which was both a function and an indicator of the ecological availability of water at shallow levels.
It seems necessary to work with farmers to ensure efficient use of water and allow the Persian wheel -a symbol of sustainable and carbon free water use- to continue its existence. Because, with its disappearance, would go a water culture and history at least 1200 years old.
This sheet is also available in French: La Roue persane en Inde