Indian Contributions to Science PDF

14. Indigenous Agriculture, Biotechnology............................. 149...

14. Indigenous Agriculture, Biotechnology............................. 149 and Nano –technology 15. Traditional Wisdom of Astronomy..................................... 154 16. India in Space: A Remarkable Odyssey.............................. 165 Contents 17. Discovery of Gravitational Waves—................................... 178 The Indian Contributions 18. Discovering Samgamagrama Madhavan...................... 180 Preface...................................................................................................vii 19. Latest Achievements July 2016 Onwards..................... 184 Vidyarthi Vigyan Manthan (VVM Edition –XIII) 2024-25...........ix Acknowledgement..................................................................................xi Syllabus: 1. India’s Contribution to Science and Technology..................1  Junior group (Class VI- VIII): Chapters 1-7 & 9-12 (From Ancient to Modern) 2. Astronomy in India....................................................................9  Senior group (Class IX- XI): All Chapters (Chapters 1-19) 3. Chemistry in India: A Survey................................................. 20 4. The Historical Evolution of....................................................30 Medicinal Tradition in Ancient India 5. Plant and Animal Science in Ancient India..........................39 6. Mathematics in India............................................................... 46 7. Metallurgy in India..................................................................58 8. Indian Traditional Knowledge on......................................... 69 Environmental Conservation 9. Ayurveda for Life, Health and Well-being: A Survey........81 10. Nobel Laureates of Indian Origin & Inspiring................89 Lives of Scientists and their contribution 11. Conventional, Non-conventional and................................. 131 Clean Energy Sources of India 12. Science and Its Various Branches........................................137 13. Ayurveda and Medicinal Plants.........................................141 vi  2 Indian Contributions to Science natural air conditioning, complex stone work and construction 1 engineering. The Indus Valley Civilization was the world’s first to build planned towns with underground drainage, civil sanitation, hydraulic engineering and air-cooling architecture. While other ancient civilizations of the world were small towns with one central complex, the Indus Valley Civilization had the distinction of being spread across a region about half the size India’s Contribution to Science and of Europe. Weights and linguistic symbols were standardized Technology (From Ancient to Modern) across this vast geography, for a period of over 1000 years, from around 3000 BCE to 1500 BCE. Water Management Water has been the life blood of most major civilizations. A dvancements in science and technology have been the major reason for the development of human civilization. India has been contributing to the fields of science and technology Criss-crossed by many great rivers, India is no exception to the rule. Indians had been developing water management techniques even before the Harappan time. Wells, ponds, lakes, dams and since ancient times. Even today, what we term as ‘traditional canals have been constructed with advanced technologies knowledge’ is actually based on scientific reasoning. throughout the historic timeline of Indian civilization. Water has been used for storage, drinking and purposes of irrigation. Pre-Independence It is estimated that even today, there are more than a million The history of scientific discoveries and man-made ponds and lakes in India. development in India dates back to the Vedic era. It is believed that ancient Indian scholars had developed geometric Iron and Steel theorems before Pythagoras had made them popular. The Iron and steel have literally been the pillars of modern concept of squares, rectangles, circles, triangles, fractions, civilization. Ancient India was pioneer in developing the and the ability to express number 10 to the 12th power, technology of producing rust-free iron. This metal from India algebraic formulae, and astronomy have all had their origins was famous in contemporary Europe for sword making. The in Vedic literature; some are stated to have been known as famous Iron Pillar of Delhi is a testimony to that technology early as 1500 BCE. The decimal system was already in use which is almost rust free even today. during the Harappan Civilization. This is evident in their use of weights and measures. Moreover, the concepts of Farming Technique and Fertilizers astronomy and metaphysics are all described in the Rig Veda, an ancient Hindu text of the Vedic era. Indian farming technology was mostly indigenously From the complex layout of Harappan towns to the developed and was ahead of its time. It included soil testing existence of the Iron Pillar in Delhi, it is evident that India’s techniques, crop rotation methods, irrigation plans, application indigenous technologies had been very sophisticated. They of eco friendly pesticides and fertilizers, storage methods for included the design and planning of water supply, traffic flow, crops, etc.  India’s Contribution to Science and Technology 3 4 Indian Contributions to Science Physics of Missile Launching Technology, India is among the top five nations of the world. Science and technology was brought into The concept of atom can be traced to the Vedic times. The the mainstream of economic planning, with the establishment of material world was divided into five elements, namely, earth the Department of Science and Technology (DST) in May 1971. (Prithvi), fire (Agni), air (Vayu), water (Jal) and ether or space DST, today, promotes new areas in science and technology and (Akasha). Paramanu (beyond atom) was considered to be the plays the role of a nodal department for organizing, coordinating smallest particle, which cannot be divided further. Nuclear and promoting science and technology in the country. energy is produced today splitting the same. Our country’s resources are used to get maximum output in Medicine and Surgery the field of agriculture and industry. Indian scientists are making Ayurveda (Ayur means life, Veda means knowledge) is path-breaking research in the fields of agriculture, medicine, probably the oldest structured system of medical science in biotechnology, cold regions research, communications, the world. Proper knowledge about various ailments, diseases, environment, industry, mining, nuclear power, space and symptoms, diagnosis and cure is the basis of Ayurveda. Many transportation. Now, India has the expertise in the fields of scholars like Charaka and Susruta have made invaluable astronomy and astrophysics, liquid crystals, condensed matter contribution to Ayurveda by inscribing in written form, as found physics, molecular biology, virology, and crystallography, in ancient manuscripts. software technology, nuclear power and defense research and development. Shipping and Shipbuilding Atomic Energy Shipbuilding was one of India’s major export industries till the British dismantled it and formally banned it. Medieval Arab The main objective of India’s nuclear energy programme is sailors purchased boats from India. Even the Portuguese, instead to use it to generate power, and apply the technology for further of buying from Europe, also obtained their boats from India. progress in agriculture, medicine, industry and research. India Some of the world’s largest and most sophisticated ships were is, today, recognized as one of the most advanced countries in nuclear technology. Accelerators and nuclear power reactors built in India and China. The compass and other navigation tools are now designed and built indigenously. were already in use in India, much before Europe. Using their expertise in the science of maritime travel, Indians participated Space in the earliest known ocean-based trading system. Indian Space Research Organization (ISRO) is the Post-Independence sixth largest space research organization in the world. It has numerous milestones to its credit since its establishment in 1969. India has witnessed considerable growth in the field India’s first satellite Aryabhatta was built by ISRO in 1975. It of science and technology post Independence. Significant was followed by many more. In 2008, Chandrayaan-1 became achievements have been made in the areas of nuclear and space India’s first mission to the moon. The Indian Space Research science, electronics and defense. India has the third largest Organization (ISRO), under the Department of Space (DOS), scientific and technical manpower in the world. In the field is responsible for research, development and operation in the  India’s Contribution to Science and Technology 5 6 Indian Contributions to Science space through satellite communications, remote sensing for an entirely indigenous effort, was completed by the eighth resource survey, environmental monitoring, meteorological expedition. The objective was to study the ozone layer and services, and so on. India is the only Third World country to other important constituents like optical aurora, geomagnetic develop its own remote-sensing satellite. pulsation and related phenomena. The National Institute of Ocean Technology has been set up for the development of Electronics and Information Technology ocean-related technologies. The Department of Electronics plays promotional role Biotechnology for the development and use of electronics for socio-economic development. Application of electronics in areas such as India has been the frontrunner among the developing agriculture, health and service sectors has also been receiving countries in promoting multidisciplinary activities in this special attention. For upgrading the quality of indigenously area, recognizing the practically unlimited possibility of their manufactured products, a series of tests and development applications in increasing agricultural and industrial production, centres and regional laboratories have been set up. These and in improving human and animal life. The National centres for electronic design and technology help small and Biotechnology Board was formed in 1982. The Department of medium electronics units. Information Technology (IT) is one Biotechnology was created in 1986. The areas which have been of the most important industry in the Indian economy. The IT receiving attention are cattle herd improvement through embryo industry of India has registered huge growth in recent years. transfer technology, in vitro propagation of disease- resistant India’s IT industry grew from 150 million US dollars in 1990/91 plant varieties for obtaining higher yields and development of to a whopping 500 billion US dollars in2006/07. In the last ten vaccines for various diseases. years, the IT industry in India has grown at an average annual rate of 30%. Council of Scientific and Industrial Research The Council of Scientific and Industrial Research (CSIR) Oceanography was established in 1942, and is today the premier institution India has a coastline of more than 7,600 km and 1,250 for scientific and industrial research. It has a network of 40 islands. The Department of Ocean Development was established laboratories, two cooperative industrial research institutions and in 1981 to ensure optimum utilization of living resources, more than 100 extensions and field centres. It plays a leading exploitation of non-living resources such as hydrocarbons and role in the fulfilment of the technological missions supported minerals and production of ocean energy. Two research vessels, by the government. FORV Sagar Kanya and FORV Sagar Sampada, are assessing and evaluating the resource potential. Surveys and exploration efforts have been directed to *** assess sea bed topography, and concentration and quality of mineral nodules. India has sent 13 scientific research expeditions to Antarctica since 1981, and has established a permanently manned base, Dakshin Gangotri. A second permanent station,  8 Indian Contributions to Science Follow Guide to Pronunciation (Chapter 2 to 6) In this course, we have used diacritical marks for words in Sanskrit and other Indian languages, that is to say, accents, dots and macrons. This is necessary in order to get their pronunciation right. Should you find those marks disconcerting at first, just keep in mind these few simple and easy principles:  A macron (¯) over a vowel makes it long; for instance rāga In every ancient culture, astronomy was born before is pronounced raaga. mathematics: there is, in fact, no need of maths to look at the  The letter c stands for ‘ch’- as in ‘Caraka’, pronounced sky, observe the periodicity of the moon’s phases, of a few ‘Charaka’. identifiable planets, the northward or southward journey of  ś (as in ‘Suśruta’) and ş (as in nakşatra) may be pronounced the sunrise on the eastern horizon through the year, or to trace more or less as ’sh’ in ‘shall’. Thus Śulbasūtra is pronounced imaginary lines between the stars. shulbasootra.  The letter ŗ(as in smŗti) may be roughly pronounced as ri, but keeping the’ i’ as brief as possible.  Other dotted consonants (d, ţ and ņ mainly) are ‘hard’, that is, pronounced by hitting the tongue on the palate. Thus ‘Āryabhata’ is pronounced ‘aaryabhatta’ with a hard sounding ‘tt’. Undotted consonants are soft, with the tongue on the teeth. For instance, in ganita, ni is hard, but ta is soft. Students who wish to know the precise correspondence between diacritics and the Devanagari alphabet may refer to the following two tables, for vowels and consonants:  9 10 Indian Contributions to Science 2 Astronomy in India The Beginnings of Indian Astronomy Some of the rings stone found at Mohenjo-daro, with rows of small drilled holes that appears to point to the sunset across the year. (Courtesy: Erkka Maula) And that is indeed how the story of astronomy always begins. In India, those beginnings are not adequately Patterns of rock art found in Kashmir, such as a double documented. The first ‘astronomical’ objects, found in the sun or concentric circles, have convinced some scholars that Andamans, belong to the palaeolithic era, some 12,000 years ago; they were depictions of a supernova and meteor showers they are calendar sticks noting the waxing and waning* of the respectively, perhaps witnessed some 7,000 years ago. Ring- moon by incising daily notches on a wooden stick. stones found at Mohenjo-daro, the largest city of the Indus civilization (2600-1900 BCE), which exhibit rows of small drilled holes, have been interpreted as calendrical devices keeping track of the sunrise at different times of the year. The perfect east– west alignment of streets in the same city has been attributed to the sighting of the star cluster Pleiades (Kṛttikā). While the above statements remain speculative, it is well recognized that ancient people everywhere felt a need to relate to the universe by tuning in to the rhythms of celestial objects. A few thousand years ago, the Rig-Veda, the oldest of the four Vedas, spoke of a year of 360 days divided into twelve equal parts and used a five-year yuga (era), probably as a first attempt to reconcile the lunar and solar years (by the addition of One of the calendar sticks found in the Andaman islands, a month after those five years). It clearly recorded a solar eclipse, apparently recording lunar phases across several months although in a metaphorical language. And it has recently been proposed that its mention of ‘3,339 gods’ was actually a reference to the 18-year cycle of eclipses known as the saros; if so, this *The apparent increase (waxing) and decrease (waning) of the points to a very early tradition of astronomical observation. A moon’s disc from new moon to full moon and back, in the course few centuries later, the Yajur-Veda considered a lunar year of 354 of a lunar month. days and a solar year of 365 days, and divided the year into six  Astronomy in India 11 12 Indian Contributions to Science The Early Historical Period The second period extended from the 3rd century BCE to the 1st century CE and was marked by astronomical computations based on the risings and settings of planets, their revolutions, etc. Jain astronomy also developed in this period, based on a peculiar model of two sets of 27 nakṣatras, two suns and two moons; it nevertheless resulted in precise calendrical calculations. This is also the period when huge scales of time were The 27 nakṣatras, with the earth in the centre. (Courtesy: M.S. Sriram) conceived of such as a ‘day of Brahmā’ (or kalpa) of 4.32 billion years, which curiously comes close to the age of the earth (4.5 billion years). Of course, there are much longer time scales to be found in Jain texts and in the Purāṇas. ṛtus or seasons of two months each. The Yajur-Veda also gave the While some scholars have discerned Babylonian and Greek first list of 27 nakṣatras or lunar mansions, that is, constellations influences at play during this and the next periods, the issue along the path of the moon on the celestial sphere. remains open. Nevertheless, such influences seem clear enough Because of the need to keep time for the proper conduct in the introduction of the seven-day week a few centuries of rituals, calendrical astronomy grew more sophisticated in BCE (late Vedic India divided the month only into two lunar the late Vedic period, with the Vedāṅga Jyotiṣa of Lagadha as fortnights or pakṣa, one light and one dark), and of the zodiac its representative text (and, if we may call it so, the first extant of 12 signs (rāśi), first recorded in the Yavanajātaka (c. 269 CE). Indian scientific text). On the basis of its own astronomical data, it has been dated between the 12th and the 14th centuries BCE The Siddhāntic Era by most scholars. The length of the sidereal day (i.e. the time There are many gaps in our knowledge after the above taken by the earth to complete one revolution with respect to period and before the start of what has been called the golden any given star) it uses is 23 h 56 min 4.6 s, while the correct value age of Indian mathematics and astronomy. Beginning in the is 23 h 56 min 4.091 s; the tiny difference is an indication of the 5th century CE, this is the Siddhāntic era, when texts called precision reached in that early age. The Vedāṅga Jyotiṣa also siddhāntas were composed — a Sanskrit word meaning discusses solstices (ayanānta) and equinoxes (viṣuva) and uses ‘principle’ or ‘conclusion’, but which applies here to a collection two intercalary lunar months (adhikamāsa) to catch up with the of conclusions or a treatise. Their chief characteristics were the solar calendar.* In some ways, this text remains the foundation use of trigonometric methods and epicyclic* models for the for India’s traditional luni-solar calendars. computations of planetary positions. *Because they were using a geocentric system, early Greek and Indian astronomers could not explain the planets’ occasional retrograde *The solar year is about 365.24 solar days, while the lunar year is, at most, 360 days. After a few years, the difference between the two will grow so motion (as seen from the earth); they assumed that the planets moved much that a month needs to be added to the lunar year to restore a broad along smaller orbits, called epicycles, whose centres revolved around coincidence between the two systems. This is the intercalary month. the earth along larger circles (the planets’ mean orbits).  Astronomy in India 13 14 Indian Contributions to Science Āryabhaṭa I (born 476 CE), working near what is today true positions of celestial bodies, and eclipses. Varāhamihira, Patna, ushered in this era with his Āryabhaṭīya, which dealt Āryabhaṭa’s contemporary, composed in 505 CE a collection concisely but systematically with developments in mathematics of five astronomical texts prevalent during his time; one of the and astronomy. Among other things, it discussed units of time five texts, the Sūrya Siddhānta, was revised later and became a and features of celestial sphere, described the earth as a rotating fundamental text of Indian astronomy; two others expounded sphere hanging in space, and produced a table of the planets’ the principles of Greek astronomy. Varāhamihira extensively mean positions. Āryabhaṭa also gave a correct explanation for discussed the revolutions of planets, eclipses, and the zodiac, both lunar and solar eclipses, and stated that the diameter of often with an astrological background. Bhāskara I (b. 600 CE), the earth is 1,050 yojanas (defining the yojana as 8,000 average the earliest known exponent of Āryabhaṭa I, provided a very human heights or about 13.6 km); this is close to the actual useful elucidation of Āryabhaṭa’s astronomy, besides improved dimension, though 12% too large. (His diameters for the planets calculation methods. and the sun are however much too small.) Many brilliant astronomers followed, dealing with issues of coordinate systems, time measurement and division, mean and A manuscript of a passage of Brahmagupta’s Brahmasphuta Siddhānta. (Courtesy: Bombay University Library) A few years later, Brahmagupta (born 598 CE), who lived near Mount Abu, mistakenly rejected Āryabhaṭa view of the earth as rotating sphere, but contributed much to calculations of the mean and true longitudes of planets, conjunctions and problems of lunar and solar eclipses, applying to all these his considerable mathematical skills. * *The celestial longitude of a celestial body (planet or star) is the arc A map showing some of India’s astronomers / mathematicians. Their dates of the ecliptic measured eastward from the vernal equinox (Aries) to of birth as well as their place of birth or work are often approximate. Note the point where the ecliptic is intersected by the great circle passing that many more names, from Baudhāyana (~ 600 BCE) to Śrīdhara (~ 800) through the body. (The ecliptic is the plane of the earth’s orbit.) ‘Mean or Āryabhaṭa II (~ 950), simply cannot be placed on the map, as the texts are silent on their locations. (Courtesy: Michel Danino, compiled from longitude’ refers to an average value, i.e. the body’s average position, various sources) while ‘true longitude’ refers to its actual position at a given time.  Astronomy in India 15 16 Indian Contributions to Science Indian astronomers could not have achieved so much Bhāskara II (b. 1114), better known as Bhāskarāchārya, without a strong tradition of observation, and the 22nd chapter brought important innovations to both astronomical and of Brahmagupta’s magnum opus, the Brahmasphuta Siddhānta, mathematical techniques, discussing in particular the mean and dealt with a variety of astronomical instruments, most of which true positions of planets, the triple problem of time, direction could be easily made by any good craftsman: among them, a and place, the risings and settings and conjunctions of the water clock (ghaṭī yantra) consisting of a bowl with a small hole planets, eccentric and epicyclic theories for their motions of at the bottom, which would sink in exactly 24 minutes (a ghaṭī) planets, and a large number of astronomical instruments. Over if placed over water; a gnomon ( a short stick kept vertically all, Bhāskarāchārya greatly improved upon the formulas and for the study of the motion of its shadow); a graduated disk methods adopted by earlier Indian astronomers. or half-disk; and a scissor-like pair acting as a compass. Those instruments and the computational techniques applied to them were both adopted by later scholars, beginning by Lalla of the 8th century. Inscription of 1128 CE recording King Ratnadeva’s donation of a village to astronomer Padmanābha for predicting a total lunar eclipse. Over 350 such inscriptions, from 440 to 1859, have been traced out. (Courtesy: B.V. Subbarayappa) Some of the instrum ents described by Lalla for astronomical o bservations. During those centuries, astronomy’s interface with the (Courtesy: S hekher Narveker) general public was mostly through calendars and pañcāṅgas (almanacs), and the prediction of eclipses, which had great Brahmagupta also authored a manual of astronomical religious and social significance. Indeed, an astronomer’s fame calculations which remained popular for centuries, as testified was guaranteed if he could accurately predict the occurrence, by Al-Biruni, the Persian savant who came to India in the 11th nature and duration of eclipses, and numerous inscriptions century as part of Mahmud of Ghazni’s entourage. Al-Biruni record a king’s reward to such an astronomer. Another interface was deeply interested in Indian astronomical techniques, wrote was architecture, and many temples show clear astronomical about them at length, and translated texts by Varāhamihira and alignments with events such as the sunrise at solstices and Brahmagupta into Arabic or Persian. equinoxes.  Astronomy in India 17 18 Indian Contributions to Science with Maṅgala or Kuja (Mars), Bṛhaspati or Guru (Jupiter) and Śani (Saturn), as moving in eccentric orbits around the sun. This achievement of the Kerala school of astronomy is truly remarkable in the light of the fact that Nīlakaṇṭha preceded Copernicus (1473-1543), the propounder of the heliocentric theory in Europe. It seems unlikely, however, that Indian heliocentrism directly influenced European advances in the field. Other Post-Siddhāntic Developments About the same time, a complex interface with Islamic astronomy took place, which, among other benefits, brought The Sringeri temple, whose mandapa is de dicated to the twelve rāśis o r instruments such as the astrolabe to India. The famous and signs of the zodiac; some of the pil lars are align ed to the sunrise on the massive yantramantra or Jantar Mantar observatories built in two solstices. (Courtesy: B.S. S hylaja) the early 18th century by the Maharaja of Jaipur, Sawai Jai Singh (1688-1743), represent a convergence between Indian, Arabic The Kerala School and European astronomy. In a general way, Indian astronomers were more interested The widespread belief that there was virtually no progress in efficient methods of computation than in theoretical models. in Indian astronomy and mathematics after Bhāskara II is based Some of the techniques used to calculate planetary positions and on a general ignorance of the intense developments that took place in the southern state of Kerala. The so-called ‘Kerala School of astronomy and mathematics’ flourished there from the 14th to the 17th century, when networks of knowledge transmission in north India were severely disrupted in the wake of repeated invasions. Parameśvara (c. 1362-1455), an author of some thirty works, was one of the foremost astronomers of this School, and the founder of the dṛk system, which improved computations of eclipses and the positions of the planets and proved to be very popular. He emphasized the need to regularly correct formulas to bring them closer to actual observations, and was said to have studied eclipses and their parameters over a period of years. He was followed by Nīlakaṇṭha Somayājī (1444-1545), who, in his landmark Tantrasaṅgraha, carried out a major revision of the older Indian planetary model for the inferior planets, Budha (Mercury) and Śukra (Venus), and described them, along  Astronomy in India 19 3 Chemistry in India: A Survey Chemistry, as we understand it today, is a relatively young discipline; it took shape in 18th -century Europe, after a few centuries of alchemical tradition, which was partly borrowed from the Arabs. (Alchemy was a semi-esoteric practice whose ultimate goal was to turn base metals into gold and discover Two views of New Delhi’s Jantar Mantar. (Courtesy: Michel Danino) an ‘elixir of life’ that would grant immortality.) Other cultures — especially the Chinese and the Indian — had alchemical eclipses yielded remarkably precise results and impressed by traditions of their own, which included much knowledge of their speed European astronomers such as Le Gentil, a French chemical processes and techniques. savant who stayed in Puducherry for two years to observe a solar transit of Venus in June 1769. Early Chemical Techniques Although traditional tables and even calculation methods In India, we can trace such techniques all the way to the survived well into the nineteenth century (witness the case of Indus civilization (3rd millennium BCE) and its antecedents. the Odiya astronomer, Sāmanta Candraśekhara Simha, who was The Harappans’ metallurgical skills have been described in the completely insulated from European astronomy and authored in 1869 a voluminous Siddhānta), the introduction of modern astronomy brought to a close India’s own developments in this science. But India, in many ways, had contributed to the growth of the new science, as some of the techniques developed by Indian astronomers and mathematicians had been relayed to Europe centuries earlier through the Arabs. Indeed, Indian astronomy interacted not only with Islamic (or Zīj) and European astronomies, but also with Chinese astronomy, in complex interplays that invariably enriched both players. A bleached bead from Harappa (courtesy: J.M. Kenoyer).  Chemistry in India: A Survey 21 22 Indian Contributions to Science module on Metallurgy in India. Pottery called for a control of Pigments were another area for skilled chemical practices, processes such as heating, fusion and evaporation. Bead-making and were required for painting (witness the famous Ajanta involved complex treatments of minerals, including bleaching murals) as well as dyeing of cotton and othertextiles. a bead with a solution of calcium carbonate, then heating it in Interestingly, sources of pigments were not limited to organic a kiln, so as to leave permanent white designs on it. materials (such as extracts of specific flowers or fruits) but Harappans also experimented with various mortars and included mineral sources, from carbon (lamp black) to arsenic cements made of burnt limestone and gypsum, among other sulphide (yellow ochre) or copper acetate (verdigris, greenish- components. Finely crushed quartz, once fired, produced blue in colour). faience, a synthetic material; it was then coated with silica (perhaps fused with soda) to which copper oxide was added Atomism in Vaiśeṣika to give it a shiny turquoise glaze. Faience was then shaped into Although it did not translate into actual chemistry, the various ornaments or figurines. The addition of iron oxide gave Indian notion of atomism deserves a brief mention. Atomism, a greenish blue tint to glazed pottery, while manganese oxide or the concept that matter is ultimately made of indivisible resulted in a maroon colour. building blocks, appeared in India a few centuries BCE as part Such techniques survived the end of the Indus civilization of philosophical speculations, in particular in the Vaiśeṣika, one and found their way to the later Ganges civilization (1st of the six philosophical systems of ancient India. The author of millennium BCE), often with innovations — glass manufacture, the Vaiśeṣika Sūtras came to be known as Kaṇāda (literally ‘eater for instance: numerous glass beads and other artefacts have been of particles’) and may have lived any time after 500 BCE. In this unearthed from Taxila in the Northwest to Nalanda in the East system, all substance was seen as an aggregated form of smaller and Arikamedu in the South. units called atoms (aṇu or paramāṇu), which were eternal, indestructible, spherical, supra -sensible and in motion at the primordial state; they could form pairs or triplets, among other combinations, and unseen forces caused interactions between them. The Vaiśeṣika system identified nine types of substance (dravya): (1 to 5) the five elements (earth or prithvi, water or ap, fire or tejas, wind or vāyu, ether or ākāśa), (6) time (kāla), (7) space or direction (dik), (8) the mind (manas), and (9) the spirit or knower (ātman). Besides, substance had twenty-four different qualities (guṇas), including fluidity, viscosity, elasticity and gravity. While fluidity was related to water, earth and fire, viscosity was unique to water, and gravity to earth. Distinctive characteristics of sound, heat and light were also discussed, which often came close to later discoveries of physics, although, lacking a mathematical apparatus, they did not evolve into scientific theories. A Harappan Bangle made of faience  Chemistry in India: A Survey 23 24 Indian Contributions to Science Chemistry in Early Literature entirely from extracts from various plants, fruits, seeds and barks which, after being boiled and concentrated, were then We find plentiful evidence of knowledge of chemical treated with various resins. It would be interesting to test and practices in some of India’s early literature. scientifically assess such recipes. Kauṭilya’s Arthaśāstra is a well-known text of governance Several texts (such as the Kāmasūtra) contain a list of and administration authored probably in the 3rd or 4th century the traditional sixty-four arts which an accomplished person BCE, during the Mauryan era. It has much data on prevailing was supposed to master. Among them, interestingly, we find, chemical practices, in particular a long section on mines and ‘Knowledge of gold and silver coins, jewelsand gems; chemistry minerals (including metal ores of gold, silver, copper, lead, tin and mineralogy; coloured jewels, gems and beads; knowledge and iron). It also discusses the various characteristics of precious of mines and quarries,’ which testifies to the attention paid to stones (pearl, ruby, beryl, etc.), details of fermented juices (from such fields. sugarcane, jaggery, honey, jambu, jackfruit, mango, etc.), and oil extraction. The Classical Age The fundamental two texts of Ayurveda are the Caraka Saṃhitā and the Suśruta Saṃhitā, both dated a few centuries Alchemy in India emerged around the mid-first millennium CE. Not only do they turn to a wide range of chemicals for CE, during the Gupta empire. Its origins remain hard to trace, medical use — metals, minerals, salts, juices — but they also and scholars have proposed that it received inputs from China, discuss the preparation of various alkalis (kṣāra), which is where the discipline is well attested as early as in the 2nd regarded as one of the ‘ten arts’ (kalā). Alkalis are described as century CE. Whatever its beginnings, Indian alchemy soon took mild, caustic or average and are prepared from specific plants: a stamp of its own. It was variously called rasaśāstra, rasavidyā after the plants have been burnt together with some limestone, or dhātuvāda; the word rasa has many meanings, such as their ashes are then stirred in water, filtered, and the resulting essence, taste, sap, juice or semen, but in this context refers to solution is concentrated by boiling, to which burnt limestone mercury, seen as one of the most important elements. Mercury and conch shells are added. Such alkalis were used to treat was identified with the male principle (Shiva), while sulphur surgical instruments as well as thin sheets of metals like iron, (gandhaka) was associated with the female principle (Shakti), gold or silver intended for the preparation of drugs. These texts and most alchemical texts were presented as a dialogue between also speak of organic acids extracted from plants such as citrus Shiva and Shakti. (Intriguingly, the genders of mercury and or tamarind (an awareness of mineral acids came much later). sulphur are the other way round in Chinese alchemy!) This is Varāhamihira’s Bṛhat Saṃhitā, an encyclopaedia of in tune with the Tantra philosophy, and indeed, in alchemical sorts composed in the 6th century CE, has a chapter on the practices, preparations and processes, mercury was regarded preparation of numeous perfumes out of sixteen fundamental as divine and assumed to be potent enough to confer not only substances mixed in different proportions. Indeed, perfumery longevity but also occult powers, including invisibility and and cosmetics formed a major branch of chemical practices in levitation. classical and medieval India. There is a vast alchemical literature, authored by savants The Bṛhat Saṃhitā also includes various recipes, for such as Nāgārjuna, Govinda Bhāgavat, Vāgbhata, Somadeva, instance for the preparation of a glutinous material to be applied Yaśodhara, among many others. The rasaśāstra texts discuss on the roofs and walls of houses and temples; it was prepared many chemical substances and their interactions. They were categorized as follows (with some variations):  Chemistry in India: A Survey 25 26 Indian Contributions to Science  mahārasas or eight major substances: mica, tourmaline, copper pyrite, iron pyrite, bitumen, copper sulphate, zinc carbonate, and mercury (sometimes lapis lazuli and magnetite or lodestone are included);  uparasas or eight minor substances: sulphur, red ochre, iron sulphate, alum, orpiment (arsenic trisulphide), realgar (arsenic sulphide), collyrium (compounds of antimony), and tintstone or cassiterite (tin dioxide).  navaratnas or nine gems, including pearl, topaz, emerald, ruby, sapphire and diamond;  dhātus or seven metals: gold, silver, copper, iron, lead, tin, zinc; a few alloys (such as brass, bronze and combinations of five metals) were also included; poisons (viṣa or garala) and plants; among the latter, over 200 are named in the Native cinnabar or mercuric sulphide texts (their identification is not always certain); plants were required, in particular, to treat or ‘digest’ metals and minerals. Transmuting base metals, such as lead, tin or copper, In the quest for the elixir of life, mercurial preparations into gold was another pursuit of alchemy, and involved five were supposed to bestow long life and youthful vigour; mercury operations: smearing, throwing, pouring, fumigating and was sometimes called amṛtadhātu or ‘immortal metal’. In impact. Here again, mercury, sometimes called svarṇakāraka practice, some Ayurvedic and Siddha medicines were derived or ‘maker of gold’, often played a major role. The processes from various metals and minerals, but only after those had described in the texts are quite elaborate, extending to many undergone complex purificatory processes so as to remove their days; their precise details cannot often be followed, however, toxic effects (or ‘kill’ them, as the texts say) and make them fit as there are uncertainties about some plants, minerals, or for internal use. For instance, although mercury compounds their treatments. But transmutation was not regarded as a are regarded as poisonous, cinnabar (mercuric sulphide, purely mechanical process: honesty, self-control, sincerity HgS) went through eighteen complex processes (saṃskāras), of purpose,devotion to God, obedience to the guru and faith including rubbing with various medicinally efficacious plant in rasavidyā were regarded as essential for the rasavādin to juices and extracts, incorporation of sulphur, mica, alkaline achieve success. Actual practices were kept secret, as the goal substances, etc. The resulting mercury compound was then would fail to be reached if they were divulged to the uninitiated. declared fit for consumption and believed to lead to the body’s devotion to God, obedience to the guru and faith in rasavidyā rejuvenation. Similar processes existed in Tamil alchemy and were regarded as essential for the rasavādin to achieve success. the Siddha system of medicine, which developed, in addition, Actual practices were kept secret, as the goal would fail to be special techniques in connection with naturally occurring salts, reached if they were divulged to the uninitiated. especially three of them (muppu), consisting of rock salts and Claims of actual production of gold out of base metals various carbonates. extend to recent times, such as a 1941 demonstration recorded on a marble slab at New Delhi’s Lakshminarayan temple; naturally,  Chemistry in India: A Survey 27 28 Indian Contributions to Science such claims must be viewed with the greatest scepticism. More glass vessels, the apparatus included specialized instruments likely, the colour of the metal was so altered that it appeared ingeniously developed for heating, steaming, distilling, golden; indeed, some texts refer to gold-looking alloys of triturating or extracting substances. Let us mention just a few silver, copper and mercury. In the alchemical tradition, the of them: transmutation of metals may also be taken as a metaphor for  the mūsa yantra or crucible, usually made of white clay or the body’s own transmutation through the elixir of life, which of the earth of an anthill mixed with rice husk, iron dust, was the ultimate objective of Indian alchemists. In any case, the chalk, etc.; such crucibles would have various shapes and quest for this elixir or the transmutation of base metals did lead sizes, depending on their application; to actual and valuable chemical techniques, in the medical field  the koṣṭhi yantra, for the extraction of ‘essences’ of metals, in particular, and eventually contributed to the Ayurvedic and consisting of two rimmed vessels, with fire urged from Siddha pharmacopoeias. above and a side blower; besides the metals, the vessels would be filled with charcoal; Laboratory and Apparatus  the svedanī yantra, a big earthen vessel used for steaming;  the dolā yantra, in which a pot is half-filled with a liquid The texts carefully spell out the layout of the laboratory, and a suspended substance absorbs the liquid’s vapours; with four doors, an esoteric symbol (rasaliṅga) in the east, furnaces in the southeast, instruments in the northwest, etc. Besides mortars (of stone or iron) and pestles, bellows (to heat the furnaces), sieves, pans, tongs, scissors and earthen or A representation of the koṣṭhi yantra (left) and the dolā yantra (right) (Courtesy: National Science Centre, New Delhi)  the pātana yantra, for sublimation or distillation; it could be upward, downward or sideways; the second was the ādhana yantra, in which a paste of mercury was coated at the bottom of the upper vessel, allowing vapours to descend into the lower vessel and combine with substances kept there;  the dhūpa yantra, used for fumigation of gold leaves or An artist’s view of an alchemical laboratory or rasasala silver foils with fumes of sulphur or other substances  Chemistry in India: A Survey 29 4 The Historical Evolution of Medicinal Tradition in Ancient India Specialization into eight branches A representation of the ādhana yantra (left) and the dhūpa yantra (right) The history of medicine in India spans a period of several (Courtesy: National Science Centre, New Delhi) thousand years, definitely dating back to a few centuries before the Common Era. There is evidence that the earliest textbooks Altogether, India’s chemical traditions were rich and of Ayurveda like Caraka Saṃhitā (General Medicine), Suśruta varied, and fused elaborate techniques with a spiritual Saṃhitā (Surgery), and Kāśyapa Saṃhitā (Paediatrics) were component. Although they may not have directly contributed edited and revised several times over a thousand years. They to the birth of modern chemistry, they did result in considerable attained their current form in the first few centuries of the practical applications, especially in fields like metallurgy, Common Era. It is an amazing fact that so early, Sanskrit gemmology and medicine. texts were composed dealing exclusively with specialties like Paediatrics, Surgery, Ophthalmology, ENT and so on. In these texts, Ayurveda is already seen in a developed form specialized into eight branches: General Medicine, Surgery, Ophthalmology-ENT-Dentistry, Paediatrics, Psychiatry, Toxicology, Rejuvenative Medicine and Reproductive Medicine. Around the 6th or 7th centuries CE, the renowned physician Vāgbhaṭa compiled the specialized knowledge of the eight branches of Ayurveda into one compendium; the larger version is known as Aṣṭāṅga Saṃgraha and the shorter version is called Aṣṭāṅga Hṛdaya. The tradition of surgery The tradition of surgery in Ayurveda has a long history. Researchers at the University of Missouri-Columbia discovered that physicians in ancient India had developed technology to  The Historical Evolution of Medicinal Tradition in Ancient India 31 32 Indian Contributions to Science The saga of Indian surgery continued to flourish and reached its acme in the time of Suśruta, who is believed to have lived in the 2nd century BCE. Suśruta is now revered as the father of surgery and advocated a thorough study of anatomy by dissecting the dead body. He introduced the method of sterilizing surgical instruments to prevent sepsis after surgical procedures. The compendium of Suśruta describes hundreds of sharp and blunt surgical instruments and many of them resemble instruments used by surgeons today. Suśruta is recognized for having developed innovative surgical procedures like reconstruction of the nose or rhinoplasty through plastic surgery, use of a specific species of ants as dissolvable sutures A mesolithic (15,000 – 6,000 BCE) rock painting from Bhimbetka, Madhya Pradesh seems to depict surgery being performed on a subject’s head or eye. to close the intestines, surgical removal of cataract, and surgical management of urinary calculi. drill teeth and remove decay 8,000 to 9,000 years ago. Study of fossils from Mehrgarh, now in Pakistan, revealed tiny holes drilled into teeth on the biting surface of male molars. Evidence has also been unearthed from Harappa and Lothal revealing an ancient surgical practice on a Bronze Age skull dating back to nearly 4,300 years ago. Trepanation, a common means of surgery practised in prehistoric societies starting with the Stone Age, involved drilling or cutting through the skull vault, often to treat head injury or to remove bone splinters or blood clots caused by a blow to the head. A folio from a manuscript of the Suśruta Saṃhitā, an Ayurvedic textbook Medical and surgical implements of 19th century origin from India. on various surgical procedures and surgical instruments. (Courtesy: (Courtesy: Science Museum, London) Wellcome Library, London)  The Historical Evolution of Medicinal Tradition in Ancient India 33 34 Indian Contributions to Science The Indian rhinoplasty technique was (re)discovered by Western medicine in the 18th century, when the East India Company surgeons Thomas Cruso and James Findlay witnessed Indian rhinoplasty procedures at the British Residency in Poona. The surgeons published photographs of the procedure and its nasal reconstruction outcomes in the October 1794 issue of the Gentleman’s Magazine of London. This painting shows Suśruta’s disciples learning surgery by working on vegetables An oculist treating a patient with specialized instruments.(Painting of 1825, courtesy The British Library, London) Medical genetics in Ayurveda In the Caraka Saṃhitā one comes across the earliest reference to the genetic basis of diseases. Caraka points out This painting by James Wales, commissioned in 1794 by two British that the reproductive element is composed of seeds (bīja) surgeons, was published along with the first known description of plastic which are further divided into parts (bījabhāga) and subparts surgery in the West. (Courtesy: Wellcome Institute, London)  The Historical Evolution of Medicinal Tradition in Ancient India 35 36 Indian Contributions to Science (bījabhāgāvayava). Each part or subpart of a seed represents a An evolving pharmacopoeia particular organ of the body and damage to the part can damage The practice of medicine in Ayurveda is based on the the organ. principle that there is no substance in the world that does not Inoculation for smallpox potentially have medicinal property. The evolution of Ayurvedic pharmacopoeia represents a continuous and unfinished quest In the 18th century, British officials and travellers for discovering new medicines from natural resources. About observed and documented the practice of inoculation for 1,500 medicinal plants have been described and formulated into smallpox, which was in vogue in India centuries before thousands of medicines in the tradition of Ayurveda. Hundreds vaccination was discovered by Edward Jenner. In an account of animals and animal products have also been mentioned in the written for London’s College of Physicians, J.Z. Holwell, texts. Around the 6th century in the Common Era, the branch of who studied and himself practised the Indian method of medicine specializing in the use of minerals and metals known inoculation, testified to its great effectiveness in preventing as Rasaśāstra developed and established itself, especially in the occurrence of smallpox. the North of India. The older tradition of herbal medicines continued to be practised in India’s southern states. In Tamil Microbiology and parasitology Nadu, the system of Siddha medicine (traditionally regarded as There are references to microbial life in textbooks of having been founded by eighteen ‘Siddhars’ or realized beings, medicine like Caraka Saṃhitā dating back to several centuries but in practice similar to Ayurveda) added to its pharmacopoeia before the Common Era. Lower life forms were classified into drugs metallic and mineral components. pathogenic and non-pathogenic. The pathogenic organisms include microbes that cannot be seen with the naked eye. Pluralistic approach to healthcare Technical nomenclature was developed for different types of Ayurveda nurtured a pluralistic approach to healthcare microbes and their shapes and sizes have also been described. in India. From ancient times, healthcare in India developed in How those physicians were able to provide such descriptions, or even conceive of microbes, centuries before microscopes were invented remains a mystery. Communicable diseases and epidemics Suśruta Saṃhitā describes communicable diseases and explains that disease can be transmitted from one person to the other by close contact, through air, sharing of clothes, sleeping together and so on. Fumigation is mentioned as a measure to prevent infectious diseases from spreading. Caraka Saṃhitā devotes an entire chapter to epidemiology and prescribes methods to prevent epidemics as well as manage the outbreak of epidemics. During the period of King Aśoka, an efficient This painting shows an Ayurvedic surgeon attending to a wound with his public healthcare system was established. surgical instruments. (Courtesy: Wellcome Library, London)  The Historical Evolution of Medicinal Tradition in Ancient India 37 the two streams of the folk and classical expressions. India has and pharmaceuticals, providing the first description of the a rich tradition of folk medicine, which was organized into a physiology of respiration. When pulse diagnosis was introduced paramedical force of health practitioners, bonesetters, poison in Ayurveda, independent treatises were composed on the healers and birth attendants who delivered primary healthcare subject. This tradition of constant updating and documentation for the people. Many of these traditions have survived into of medical knowledge continued without a break right up to modern times. Today India is perhaps the only country in the colonial period. In the 19th century, Ayurveda suffered the world that officially recognizes a pluralistic healthcare a setback when unfavourable policies and regulations were system patronizing medical systems like Ayurveda, Yoga and enforced by the colonial rulers. However, with the publication Naturopathy, Unani, Siddha and Homoeopathy. of the main Ayurvedic texts, a revival set in around the turn of the 20th century, with a few leading Indian scholars coming out Cross-cultural interactions in defence of the discipline. Ayurveda benefited from cross-cultural interactions and Global resurgence of Ayurveda spread out of India into neighbouring countries like China, Sri Lanka, Tibet, Thailand and Indonesia. Buddhism played a major In the post-independence period, Ayurveda’s resurgence role in the spread of Ayurveda outside India. When Alexander continued, and in recent years it has been gaining prominence the Great invaded India in 325 BCE, he was so impressed by the as a whole system approach to healthcare under the banner of snakebite healers and Ayurvedic physicians that he invited them Complementary and Alternative Medicine. Although it is not to Greece. There is historical evidence indicating interactions the West, Ayurveda is taught and practised in many countries between the physicians of Greek medicine and Ayurveda. like Germany, Italy, United Kingdom, Austria, Netherlands and Important textbooks of Ayurveda like Caraka Saṃhitā, Suśruta so on. There are many schools of Ayurveda in the United States. Saṃhitā and Aṣṭāṇga Hṛdaya were translated into Tibetan, Persian and Arabic languages in the Middle Ages. Contemporary status Ayurveda Travellers from China and the Middle East narrated in Continues to manage a wide range of conditions effectively their accounts the advanced state of medical practice in India. like chronic degenerative diseases and life style disorders and is being sought after by people around the globe. As the world A dynamic literary tradition is moving towards an integrative approach to healthcare, The history of Ayurveda reveals the evolution of a vibrant Ayurveda continues to inspire visions of healing that is holistic, and dynamic medical tradition with compendia, medical pluralistic and integrative at the same time through a tradition lexicons, pharmacopoeias, handbooks, manuals of treatment that has exhibited remarkable continuity, resilience and and so on being composed at important chronological and adaptiveness to the vicissitudes of time. geographical landmarks. For example, in the 8th century CE, a treatise devoted exclusively to diagnostics was composed by Mādhava known as Mādhava Nidāna. In the 11th century, a new treatise was composed on dietetics by Viśvanātha Sena called Pathyāpathyaviniścaya. In the 13th century the Śārngadhara Saṃhitā was composed on the subject of pharmacy  40 Indian Contributions to Science are also independent works on the subject like Surapala’s 5 Vrksayurveda and Upavana Vinoda of Sarngadhara. The legacy of Vrksayurveda has also been preserved through folk traditions in oral form. The farming and tribal communities constitutes the largest repository of the working knowledge of Plant and Animal Science in plant science in India. Surapala applied the dosa theory to plants to provide a Ancient India number of recipes for plant protection and treatment, depending on the particular dosa imbalance affecting the plant. Many of the ingredients he lists have been shown to possess antimicrobial properties. Among them are milk (elephant milk at times!), ghee, Ayurveda also represent Life Sciences like Botany, Zoology, honey, licorice, cow urine and dung, various liquid manures, Veterinary Science and agriculture along with medicine. Plant mustard, pastes made of various barks and roots, asafetida, science was known as Vrksayurveda and Animal science turmeric, sesame oil, salt and ash; the flesh, fat or marrow from as Mrgayurveda. Asvayurveda and Gajayurveda represent various animals (mammals and fish) was also recommended in Veterinary Medicine for horses and elephants respectively. specific cases. Agriculture was known as Krsisastra. Plant Science in Ancient India Antiquity and continuity Knowledge of plants and agricultural practices are documented in ancient Indian literature. Discussions on plant science can be seen in Vedic literature, the epics and various compendia. Sources Arthasastra of Kautilya contains very interesting passages relating to the harvesting and management of crops and crop diseases and very many aspects of agroforestry. Brhat Samhita of Varahamihira composed in the 6th Century CE has an entire chapter devoted to Vrksayurveda. Agni Purana also includes a chapter on the topic. Cakrapanidatta, a commentator of the Folios from the manuscript of Vrksayurveda of Surapala, a text on plant science composed in the 10th century. (Courtesy: Asian Agri-History celebrated Ayurvedic text, Caraka Samhita, puts forth the Foundation, Secunderabad) theory that plants have feelings and cognitive abilities. There  Plant and Animal Science in Ancient India 41 42 Indian Contributions to Science Scope pest and disease management, nomenclature and taxonomy, description and classification of plants to get varied purposes, Ayurvedic literature refers to plants and their classification favorable and unfavorable meteorological conditions. Use of into forest trees, other trees, shrubby plants and herbs. Shrubby plants as indicators of weather, water, and minerals as well as plants are either climbers or shrubs as such and herbs are botanical marvels. flowering and non- flowering. Flowering and an non-flowering trees are also distinguished. Vrksayurveda includes topics like Validation collection, selection and storage of seeds, germination and sowing, various techniques of plant propogation and grafting, The Indian Council of Agricultural Research (ICAR) has nursing and irrigation, testing and classification of soil, selection documented 4,879 indigenous practices in the field of traditional of soils suitable for various plants, types of plants, manuring, plant science. A set of 111 indigenous technical practices were selected and subjected to experimental testing and validation in efforts that were conducted by several ICAR institutes and state agricultural departments and universities across the country. These pertain to various topics such as pest control, crop protection, farm implements, weather forecasting etc., and it was shown that slightly more than 80% of these practices were valid and about 6% were partly valid. Vrksayurveda promises many new areas for fresh research initiatives like the study of meteorological conditions (tithi, naksatra) that are suitable for various agricultural operations in the cultivation of crops, increasing plant growth and yield, testing and classification of soil and use of plants as indicators for water, minerals and Preparation of extract from neem kernels to treat crops against pests and weather. diseases. (Courtesy: Centre for Indian Knowledge Systems, Chennai) Animal Science in Ancient India Antiquity and continuity The branch of veterinary medicine was well developed in ancient India and was devoted to the well being of domesticated animals like cows, horses and elephants. Earliest references can be seen in vedic literature. Sources Preparation of extract from garlic, ginger and chilli to treat crops against pests and diseases. (Courtesy: Centre for Indian Knowledge Systems, Hayayurveda of Salihotra is an ancient textbook of Chennai) veterinary medicine that classifies horse and describes  Plant and Animal Science in Ancient India 43 44 Indian Contributions to Science on the basis of varied criteria. Animals are reproduced sexually (yonija) or asexually (ayonija). Sexual reproduction is either through eggs (oviparous) or placenta (viviparous). The texts also speak of life emerging from moisture and heat as well as from head vegetation. One classification distinguishes animals by number of feet and another by the presence or absence of hoofs. The Matsyapurana classifies animals on the basis of their activity into diurnal, nocturnal or both. A number of animals have been described in the context of food and dietetics. The medicinal and nutritional properties of meat from a variety of animal sources have been documented in the classical text of Ayurveda. The food web and food chain have been described highlighting the principle that one form of life is food for another (jivo jivasya jivanam). People of ancient India lived in close proximity with nature and were ken observers of animal life. It has been mentioned in some text that the first clues regarding medicinal properties of (Left) A veterinary surgeon performing surgery on the eye of a horse. plants can be discovered from animal behaviour. Thus ancient (Right) A veterinary surgeon performing bloodletting on a horse. Indian literature has one of the earliest documented evidence (Courtesy: Wellcome Library, London) of the practice of zoo-pharmacognosy, that is, the discovery of medicinal uses of plant by observing how animals eat specific treatments for horses apart from providing accounts of plants when they suffer from a disease, have worm or have anatomy. Salihotra composed many treatises on horses, which been bitten by a snake. were translated into Arabic, Persian and Tibetan. A treatise on The texts of Ayurveda also talk about confirming the Gajayurveda devoted to elephants was composed by Palakapya toxicity of substances by administering test doses to animals, which deals with treatment of diseases afflicting elephants. The perhaps the earliest account of animal experiments in toxicology. Mrgapaksisastra by Hamsadeva composed in the 13th century CE gives fascinating descriptions of animals and birds. Current status Scope Gajayurveda is still practiced by traditional experts in states like Kerala. Veterinary herbal medicines are manufactured The diversity of animal life has been well captured in the and marketed by pharmaceutical firm in India. ancient literature of India. The canons of Caraka and Susruta classify animals on the basis of their habitat and predatory Biodiversity and folk traditions behaviour. Animals are classified on the basis of habitat into terrestrial, underground, aquatic, aerial and marshy types. The richness of the biodiversity and the climatic and Animals are prey snatchers (prasaha), peckers (viskira) or geographic variations were highlighted in ancient writings. attackers (pratuda). In different text, animals have been classified Different geographical regions were described along with the  Plant and Animal Science in Ancient India 45 cycle of six seasons setting the stage for variations in biodiversity. It is mentioned in Ayurvedic texts that there is a variation of biodiversity in term of flora and fauna as well as human life and 6 habits over a span of 12 yojanas or 96 miles. Ancient Indians estimated that there are nearly 8.4 million yonis or species of life on earth. This comes strikingly close to the recent estimate of modern scientists at 8.7 million species. Susruta proclaims Mathematics in India that one must hunt for the earth is bountiful everywhere. There are about 4,600 ethnic communities in India who have lived in close proximity with nature and nurtured a folk system of medicine. It is estimated that there are one million specialized As early Indian astronomers tried to quantify the paths carries of folk medicine, outnumbering the paramedics on the of the sun, the moon, the planets and the stars on the celestial payroll of the government. sphere with ever more accuracy, or to predict the occurrence of eclipses, they were naturally led to develop mathematical tools. Astronomy and mathematics were thus initially regarded as inseparable, the latter being the maid-servant of the former. Indeed, about 1400 BCE, the Vedāṅga Jyotiṣa, the first extant Indian text of astronomy, states in two different versions: Like the crest on the head of a peacock, like the gem on the hood of a cobra, jyotiṣa (astronomy) / gaṇita (mathematics) is the crown of the Vedāṅga śāstras [texts on various branches of knowledge]. In fact, jyotiṣa initially referred to astronomy and mathematics combined; only later did it come to mean astronomy alone (and much later did it include astrology). First Steps India’s first urban development, the Indus or Harappan civilization (2600-1900 BCE), involved a high degree of town planning. A mere glance at the plan of Mohenjo-daro’s acropolis (or upper city), Dholavira (in the Rann of Kachchh) or Kalibangan (Rajasthan), reveals fortifications and streets generally aligned to the cardinal directions and exhibiting right angles. Specific proportions in the dimensions of major structures have also been pointed out. All this implies a sound knowledge of basic geometric principles and an ability to measure angles, which the discovery of a few cylindrical compasses made of shell, with slits cut every 45°, has confirmed. Besides, for trading purposes  Mathemathics in India 47 48 Indian Contributions to Science Early Historical Period The first Indian texts dealing explicitly with mathematics are the Śulbasūtras, dated between the 8th and 6th centuries BCE. They were written in Sanskrit in the highly concise sūtra style and were, in effect, manuals for the construction of fire altars (called citis or vedis) intended for specific rituals and made of bricks. The altars often had five layers of 200 bricks each, the lowest layer symbolizing the earth, and the highest, heaven; they were thus symbolic representations of the universe. A few Harappan weights made of chert, from Dholavira, Gujarat (Courtesy: ASI) the Harappans developed a standardized system of weights in which, initially, each weight was double the preceding one, then, 10, 100 or 1,000 times the value of a smaller weight. This The first layer of one kind of śyenaciti or falcon altar described in the Śulbasūtras, made of 200 bricks of six shapes or sizes, all of them adding up shows that the Harappans could not only multiply a quantity to a specified total area. by such factors, but also had an inclination for a decimal system of multiples. However, there is no agreement among scholars Because their total area needed to be carefully defined and regarding the numeral system used by Harappans. constructed from bricks of specified shapes and size, complex There is no scholarly consensus on the dates of the four geometrical calculations followed. The Śulbasūtras, for instance, Vedas, India’s most ancient texts, except that they are over 3,000 are the earliest texts of geometry offering a general statement, years old at the very least. We find in them frequent mentions of in geometric form, of the so-called Pythagoras theorem (which numbers by name, in particular multiples of tens, hundreds and was in fact formulated by Euclid around 300 BCE). thousands, all the way to a million millions in the Yajur Veda — a They spelt out elaborate geometric methods to construct a number called parārdha. (By comparison, much later, the Greeks square resulting from the addition or subtraction of two other named numbers only up to 10,000, which was a ‘myriad’; and squares, or having the same area as a given circle, and vice-versa only in the 13th century CE would the concept of a ‘million’ be — the classic problems of the squaring of a circle or the circling adopted in Europe.) The Brāhmanas, commentaries on the Vedas, of a square (which, because of π’s transcendental nature, cannot knew the four arithmetical operations as well as basic fractions. have exact geometrical solutions, only approximate ones). All  Mathemathics in India 49 50 Indian Contributions to Science A few centuries later, Piṅgala’s Chandasūtras, a text on Sanskrit prosody, made use of a binary system to classify the metres of Vedic hymns, whose syllables may be either light (laghu) or heavy (guru); rules of calculation were worked out to relate all possible combinations of light and heavy syllables,