
Nectar of life
Everyone knows that water is a must for survival, and you would have often observed plants in your terrace wither or wilt due to shortage of water.
It is however a lesser-known fact that water has been an essential ingredient for the very evolution of life, and the earliest life forms on earth originated in craters having water, and other organic ingredients. By this you would better appreciate the significance of the presence of water that various missions exploring existence of extraterrestrial life keep exploring. By this you can also understand the excitement of the scientific community over the discovery of the presence of water reserves on Mars.
Availability, and abundance of water at any place is generally governed by the rules of hydrological cycle. As regards the Indian subcontinent; most water received out here is owed to the southwest (SW) monsoon. The situation was however not always the same. The SW monsoon stabilized over the subcontinent only after the collision of Indian, and Eurasian plates that resulted in the evolution of the Himalayan mountain belt during the Miocene times (around 40-50 million years before present). This orographic barrier restricted northward drift of the water saturated monsoon clouds, and facilitated rainfall in the subcontinent; particularly so in the Himalayan region.

Despite receiving ample rainfall, major portion of the precipitation in the Himalayan region is however restricted to the monsoon season. Moreover the topography of the terrain promotes fast runoff, and the precipitated water is therefore soon unavailable for any productive purpose. Moreover the water of the glacier fed rivers of Himalaya is not fit for human consumption both during summer, and rainy seasons; melting of glaciers during the former enhances silt load in the water while during the latter surface erosion makes the water unfit for consumption. It is therefore no wonder that many habitations in the Himalayas located in the proximity of perennial glacier fed rivers often face shortage of drinking water, particularly during the summer season when demand is at its peak as also river discharge.
Human habitation in the Himalayas
Availability of drinking water in adequate quantities, and all through the year being a major prerequisite for survival, the questions relating to the establishment, and expansion of human habitations in the Himalayan region are not easy to address as requirement of many major hill habitations, particularly those located on the ridges are presently fulfilled by water pumped from far off places.
The primitive pump called shadoof that consists of a bucket tied to a rope at one end of a pole counterbalanced on a pivot, was utilized to lift water from well by the Mesopotamians since 3000 BC, ancient Egyptians since 2000 BC, the Minoans, Chinese since 1600 BC, and by many others. It is interesting to note that this primitive technology is still used in many parts of Africa, and Asia. These pumps are in fact common in rural areas of India, and Pakistan, and are identified as dhenki in the Bhojpuri belt of the Ganges plains.
Shadoof could not however be employed to lift water over long distances as is required for satisfying water related needs of the Himalayan habitations, and the one capable of doing so was only invented in 1687 Frenchmen Denis Papin.

Due to the constraints put forth by nature, unlike most ancient civilizations the early inhabitants of the Himalayan region did not enjoy the luxury of settling down in river valleys that provided these civilizations year round plentiful availability of water, access to fertile land for agriculture, means of transport and strategic advantage. These people could therefore devote their time towards other productive pursuits.
Rather than technology the human habitations in the Himalayan region thus thrived on human ingenuity, and quest to overcome adversities.
Optimal utilisation
Learning the art of effective, and optimal utilization of available water, as also developing alternative sources, though essential for growth, and expansion of habitations, is a time consuming process. It invariably involves observation, exploration, experimentation, and analysis over generations, and effective assimilation, and transmission of this accumulated knowledge before it is utilized by some of the descendants.
Until some breakthrough could be managed, the early settlers of the Himalayan region were left with no choice but to survive, and thrive on the booty of spring fed local streams together with the water seeping out of the hill slopes along joints, fractures, and other discontinuities present in the rock mass.
Though ensuring survival this restricted geographical spread of habitations to the proximity of seasonal streams. Depleted discharge of many of these, particularly during the summers was an added constraint.
Even though the seepages were available on higher elevations utilizing these conveniently was a major challenge, and these were at the same time fraught with uncertainly of going unproductive during summers. A method had therefore to be devised for using the seepages conveniently, and ensuring their longevity during summers.
Dhara
If you have ever come across seepages in the mountains you would have observed water oozing out, or tickling at a very slow pace. You would agree that it is really hard, and cumbersome to practically use this water. This water has therefore to be accumulated somewhere and for some time before being utilized productively, and efficiently.
Stone chamber
The early settlers thus experimented with the idea of carving out a chamber around the site of the seepage, and getting the seeping water collect in these. This was however much complicated than it sounds as the evolutionary history of the terrain has rendered the rock mass with numerous joints, and fractures. Most efforts of carving out chambers would have therefore gone futile but the successful ones would have certainly provided important lessons for checking site suitability, and ensuring desired results. An algorithm would have thus evolved, and passed on.

Regulated flow
The chamber thus created painstakingly in the rock mass harvested the water oozing out of the hill slope. A mechanism was however still needed for ensuring regulated, and continuous discharge of this collected water for using it conveniently. A stone with a through hole was the solution arrived at for this. Water collected in the stone chamber thus started to flow through the passage provided in the stone.
The animal head
The exposed portion of this stone was often sculptured in the shape of some animal head or motif. Water thus flowed out of the mouth of the animal head or motif in an aesthetically pleasing manner.
This animal head or motif must have held some religio-magical significance, and would have served some social ends; mere aesthetic pleasure being a luxury these people could hardly afford.
Religio-magical ends
The impact of flowing water would have eroded the ground below, and adversely affected the utilisation of water. Stone slabs were therefore laid down at the place where the running out water fell on the ground. Besides preventing erosion of the soil beneath, this ensured cleanliness of the surrounding area.
Presence of water in ample quantities would have promoted luxurious vegetation growth in the proximity of the water source, often referred to as dhara and amongst these peepal (Ficus religiosa), considered sacred was particularly nurtured. Besides providing shade the peepal tree served various religio–magical purposes.

A circular dry stone platform was often constructed around the stem of the chosen peepal tree in the proximity of the dhara where figurines of local deities were also established. This platform provided a convenient place for carrying out various religio-magical rite,s and the sacred lamp placed in the proximity of the deity was dutifully lighted in the evening by the community members.
The dhara was thus a combination of various sorts at one place; sacred animal or motif, life giving water, presence of the deity and the sacred peepal tree. This ensured cleanliness, and maintenance of these water sources voluntarily by the community.
[…] reserves are also easy to locate and exploit in middle and lower slopes, and therefore not many naulas are located in the higher […]