The earliest evidence of technological progress in the Indian subcontinent is to be found in the remains of the Harappan civilization (4000-3000 BC). Archaeological remains point to the existence of well-planned urban centres that boasted of private and public dwellings laid out in orderly fashion along with roads and drainage systems complementing them. The drainage systems were particularly remarkable for the times since they were built underground and were constructed in a manner to allow for regular cleaning. Smaller drains from private homes connected to the larger public drains.
Larger private dwellings were invariably multi-storied and all homes were constructed from standardized fired bricks and provided for separate cooking areas and toilets. Storage facilities for grain and goods for trade were built as were public baths and other buildings intended for various public functions.
Urban centres were often planned near riverine or sea-ports. Accurate weights and measures were in use and ports such as Lothal were developed as export centres of early manufactured products from smelted copper and bronze. Kilns for smelting copper ingots and casting tools were in existence as were metal tools such as curved or circular saws, pierced needles and most significantly, bronze drills with twisted grooves. The drill enabled the production of items with unparalleled precision for the times and could be regarded as an ancient precursor of the modern machine tool.
There is also evidence of planned irrigation systems and it appears that fire and flood control measures to protect farms and villages were also in place. Artisans made use of the wheel and clay pottery was decorated in a variety of colors and designs. Cotton was grown and used to produce textiles.
Urban centres in the Harappan region traded with each other as well as with counterparts in Babylon, the Persian Gulf, Egypt and possibly the Mediteranean. The span of the Harappan civilization was quite extensive, and included much of modern Sindh, Gujarat, Rajasthan, Haryana, Punjab and Western UP.
But prior to it's disappearance, there is also evidence of considerable social decay and disintegration. Excavations from the later phases of the Harappan civilization suggest that population pressures led to greater anarchy in building construction. Urban dwellings became smaller and settlements became more haphazard indicating a breakdown of social mores and structures that promoted urban regulations and enforced construction codes.
Social Conditions and Technological Progress
It is quite possible that the decline in civil society extended to other areas such as agricultural planning and maintenance of irrigations systems making the civilization more vulnerable to natural disasters such droughts, floods, fires or earthquakes - thus contributing to the eventual extinction of that vibrant civilization. This suggests that technological progress cannot be divorced from social conditions that may either encourage the progress of technology or conversely cause civilizations that may be (in relative terms) quite advanced to stagnate and even decline.
For instance, 3000 years after Harappa, we find anecdotal evidence of impressive urban settlements constructed during the Mauryan period. Greek travellers have left behind admiring descriptions of Patliputra - the Mauryan capital. But social strife brought a precipitous end to the grand civilization. The growth of a parasitic, exploitative and socially oppressive elite led to massive social upheavals. In the course of the civil wars, fires and looting destroyed virtually all of the wood-based dwellings including grand palaces and public buildings.
Thus, an entire tradition of wood-based urban construction - (which may have taken several centuries to develop) was destroyed. But it also led to a greater emphasis on the use of more lasting construction materials. The very social conditions that destroyed technological progress in one direction gave birth to technological progress in another. Sculptural finds from the Mauryan period indicate that Mauryan sculptors of that time had achieved a high degree of proficiency in working with stone. They must have had tools and implements that enabled them to create smoothly modelled and highly polished representations of human and animal figures. Later civilizations in India employed these skills not only for the purposes of sculpting but for creating entire monuments constructed from a variety of hard building materials. For instance, various methods for preparing cements were developed, and by the 7th century, cement of highly durable quality came into use in the construction of important monuments that survive to this day.
The Impetus for Metallurgy
Monumental architecture required considerable advances in the technology of lifting, loading and transportation of construction materials, building construction ramps, scaffolding, and related tools and implements. As in ancient Egypt or Babylon, appropriate techniques also had to be developed and implemented in India. But more importantly, stone-based construction presupposes the existence of hard metal based tools and implements for cutting and shaping stone. The discovery of iron thus played an essential role in the development of monumental architecture in India which may have in turn given a further impetus to the development of metallurgical skills.
As early as the 4th C. BC, Kautilya's Arthashastra had a section outlining the processes for metal extraction and alloying. Later Sanskrit texts talk about assessing metal purity and describe techniques for achieving metal purity. Various alloying techniques were in use and some may have had their origin in the Harappan or Vedic periods. (For instance, there are references in the Vedic literature that suggest that copper vessels were coated with tin so as to prevent milk from going sour.)
A combination of scholarly investigation and broad dissemination of practical techniques propelled the development of metallurgical skills. The fifth century Iron Pillar of Delhi is a remarkable example of those skills. Standing over 23 feet high it consists of a single piece of iron and has weathered over 1500 monsoons without showing any signs of rust. The pillar is made of wrought iron with an iron content of 99.72 % and appears to have been protected from rust by the application of a thin coating of manganese dioxide.
By the 12th century, construction engineers were using iron girders and beams on a scale unknown in any other part of the world. The most significant use of iron beams was in the temples of Puri and Konarak. The Puri temple contains 239 iron beams and one of the beams in Konarak is 35 feet long. All are 99.64 percent iron and were produced in a similiar manner to the Delhi iron pillar.
During the middle ages, India acquired a reputation for producing very high quality steel and was also able to extract zinc from it's ore by the 14th century. Bidari (an alloy of copper, lead and tin developed in the Deccan) was also extensively used.
Unsurprisingly, developments in metallurgy also had their impact on artillery production. According to A. Rahman (Science in Medieval India), by the 16th century, the heaviest guns in the world were being cast in India and a variety of weapons were being manufactured in the subcontinent. The Jaigarh cannon factory was one of India's best and before the crucial battle of 1857, the Jaipur Rajputs laid claim to owning Asia's largest cannon. Yet, none of the Rajput cannons were ever used to confront the British who succeeded in conquering the sub-continent without ever having to fight against the country's best equipped armies, thus demonstrating that technological progress is not an end in itself.
Social Needs and Technological Applications
More often than not, social needs (as arising from geographic, climactic or living conditions) have been the primary impetus for technological progress in society. The long dry months that most regions of India had to deal with led to numerous innovations in water-management techniques. Irrigation canals, wells of different types, storage tanks and a variety of water-harvesting techniques were developed throughout the sub-continent. The Harappans were not alone in creating water-management solutions. Irrigation works of enormous size were undertaken time and time again. The reservoirs at Girnar in Kathiawar (built in the 3rd C. BC) had an embankment over 100 ft thick at the base. The artificial lake at Bhojpur (near Bhopal) commisioned by Raja Bhoj in the 11th C covered 250 sq. miles. In the South, also in the 11th C., an artificial lake fed by the Kaveri river had a 16-mile long embankment with stone sluices and irrigation channels. Rajput kings built artificial lakes throughout the desert state of Rajasthan, but irrigation schemes were essential to agricultural prosperity even in Kashmir, Bengal and the delta regions of the South.
The need for accurate prediction of the monsoons spurred developments in astronomy while the intense heat of the summer led to innovations in architecture. In Rajasthan and Gujarat step-wells were built deep into the ground - sometimes descending as much as a hundred feet and large scale observatories were built in Benaras, Mathura and Ujjain to facilitate advances in the astronomical sciences. Bengal became known for it's fine muslins that were light and airy to wear in the warm and humid climate of the state. Techniques for pickling and preserving fruits, vegetables, fish and meats were developed throughout the country to prevent or delay spoilage. Manually operated cooling devices were also invented. The Arthashatra mentions the variyantra (probably a revolving water spray for cooling the air). Technology thus arose in response to compelling material needs.
Scientific Rationalism and Technological Efficacy
But technological progress also requires a favorable social milieu. A foundation of scientific knowledge, rational thinking and practical experimentation can be essential to the process of making technological discoveries (although the application of already known technologies can occur more easily). As mentioned in the essay: Development of Philosophical Thought and Scientific Method in Ancient India numerous technological inventions occurred in parallel with developments in rational philosophy and advances in mathematics and natural sciences.
This is not to say that Indian society was entirely rational. In all ancient societies (and even modern ones), superstitions, religious beliefs, reliance on astrology, numerology or the advice of 'seers', palmists and fortune-tellers have impinged on the scientific process and consequently hindered the progress of technology. In the civilizations of ancient Egypt, Babylon and India - we see numerous instances of scientifically accurate statements and practical truths mixed up with religious myths and popular superstitions. This was especially true in the science of medicine. Genuine cures were listed with unscientific practices without clear distinction. But during the rational period in India the emphasis on the scientific method led to a much greater level of veracity with respect to the efficacy of different medicines and medical procedures.
The more accurately the Indian medical practitioner was able to observe reality, understand bodily functions and test the efficacy of popular medical techniques, the more successful were the prescribed cures. Dissection of corpses and careful monitoring of different diseases was an important component in the study and practice of medicine. With greater success in treatment came greater confidence and allowed medical practitioners to conduct surgical procedures using a variety of surgical tools - albeit primitive in comparison to modern surgical equipment.
Procedures for inducing unconsciousness or numbing body parts that were to be operated on were required and developed. Tools for excision, incision, puncturing, probing, organ or part extraction, fluid drainage, bloodletting, suturing and cauterization were developed. Various types of bandages and ointments were used as were basic procedures for ensuring cleanliness and limiting contamination. The caesarian section was known, bone-setting reached a high degree of skill, and plastic surgery developed far beyond anything known elsewhere at the time. Indian surgeons also became proficient at the repair of noses, ears and lips lost or injured in battle or by judicially mandated mutilation. By the 1st C. AD the foundations of this rather evolved medical system were in place and by the 4th C. - much of this knowledge was standardized and available in the classical textbooks of Charaka and Susruta.
While all ancient societies cherished and admired the skills of the medical practitioner, it was the more determined adoption of the scientific approach that enabled Indian medicine to make a quantum leap over the older medical systems of the time.
{Progress in medicine also led to developments in chemistry and chemical technologies. The manufacture of alkaline substances, medicinal powders, ointments and liquids was systematized, as were chemical processes relating to the manufacture of glass. Advances in food processing (such as manufacture of sugar, condiments and edible oils) took place as did the manufacture of personal hygiene products and beauty aids (such as shampoos, deodorizers, perfumes and cosmetics).}
Cultural Mores and Technological Innovation
Cultural preferences also impelled technological innovations. During the rational period, considerable attention was paid to human psychological processes. The analysis of moods and emotions led to elaborate theories on the role of color and design in inducing psychological well-being. Treatises on art and architecture emphasized the importance of color. As a result, the use of color in decorating household artifacts, textiles, furniture, and public and private dwellings became widely prevalent and a matter of conscious choice.
Discoveries concerning the manufacture and application of natural and artificial dyes quickly followed. Block printing, tie and dye, and other textile-dyeing techniques were popularized. The use of mordents in color-fast dyeing of textiles became known as did the knowledge of lacquers that could be applied to wood