π Science in India Β· Part 2
Ancient and classical contributions
Harappan engineers, Vedic geometers, Gupta-age astronomers, the mathematicians of the Kerala School and the scholars who carried Indian numerals to the world β field by field, from the earliest towns to about 1800, as NCERTβs textbooks describe them.
On the map
Only places already on YugMapβs map are shown. Maps show Indiaβs boundaries as officially depicted by the Government of India.
β Mathematics
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Harappan civilization
Standard weights
π Harappan citiesA precise system of weights, usually cubes of a stone called chert, regulated trade.
NCERT adds: The lower denominations were binary (1, 2, 4, 8, 16, 32) and the higher ones decimal (160, 200, 320, 640); the smaller weights were probably for jewellery and beads. π NCERT Themes in Indian History I, Ch. 1 (Bricks, Beads and Bones) β
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Harappan period
Scales and units of length
π Harappan sitesObjects with ruled markings that could be scales have been found at Harappan sites. Later Indian literature names units such as the angula (finger width), dhanusa and yojana, used for artefacts, architecture and town planning β and carpenters and tailors still use the angula.
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Vedic period
Number names and fractions in the Vedas
The Yajurveda Samhita lists names for powers of ten β eka, dasha, shata, sahasra, ayuta and on up to 10ΒΉΒ² and beyond; the Rig Veda calls the fraction three-quarters tri-pada.
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c. 800 BCE (Baudhayana)
The Sulba-sutras: geometry with a rope
Geometric texts of the Vedic period on building fire altars β the earliest known Indian texts with methods to construct perpendiculars and perpendicular bisectors, using a rope as the compass. Baudhayanaβs Sulbasutra (c. 800 BCE) already works with non-unit fractions.
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as early as the 3rd or 4th century CE
Zero: the Bakhshali manuscript
π Bakhshali (now in Pakistan)A mathematical text with hundreds of zeros written as dots β the oldest recorded origin of the zero symbol we use today.
NCERT adds: NCERT: the first known instance of numbers written with ten digits, including 0 (then a dot), is the Bakhshali manuscript (c. 3rd century CE). π NCERT Ganita Prakash, Grade 8 Part 1, Ch. 3 (A Story of Numbers) β
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499 CE
Aryabhata computes with ten digits
Aryabhata was the first mathematician to fully explain, and do elaborate scientific computations with, the Indian system of ten symbols; he also first proposed a systematic way to solve problems with a single unknown.
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born 598 CE
Brahmagupta: rules for zero
π BhillamalaIn the Brahmasphutasiddhanta he gave the rules of arithmetic with zero, negative numbers and fractions. His works were later translated into Persian and Latin.
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6thβ10th centuries
Bhaskara I and trigonometry
Bhaskara I did pioneering work in trigonometry and wrote a lengthy commentary on the Aryabhatiya.
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628 CE
Brahmaguptaβs rules for fractions
The Brahmasphutasiddhanta first stated in general form how to add, subtract, multiply and divide fractions β the methods still taught today. These ideas reached Europe through the Arabs.
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c. 700 CE
Virahankaβs numbers
Counting the rhythms of short and long syllables in poetry, the Prakrit scholar Virahanka gave the rule for the sequence 1, 2, 3, 5, 8, 13, 21β¦ β the first known person to write it down. It is now called the VirahankaβFibonacci sequence.
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9th century
Indian numerals reach the Arab world
π BaghdadSanskrit texts of mathematics, astronomy and medicine were translated into Arabic. The Arabs adopted Indiaβs decimal numeral system with the zero; in Europe these became known as βArabic numeralsβ.
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c. 825 CE
Al-Khwarizmiβs βHindu numeralsβ
π BaghdadThe Indian number system reached the Arab world by around 800 CE and was popularised there by Al-Khwarizmiβs book On the Calculation with Hindu Numerals (c. 825) and Al-Kindiβs On the Use of the Hindu Numerals (c. 830).
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c. 850 CE
Mahaviracharyaβs Ganita-sara-sangraha
Mahaviracharya developed the arithmetic of fractions further and, in the Ganita-sara-sangraha, named the powers of ten up to 10Β²Β³.
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10th century
The Chautisa Yantra magic square
π KhajurahoThe first recorded 4 Γ 4 magic square, in an inscription at the Parshvanath Jain temple: every row, column and diagonal adds up to 34.
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born 1114
Bhaskaracharyaβs Lilavati
π probably present-day MaharashtraOne of Indiaβs greatest mathematicians and astronomers: Lilavati (1150 CE) teaches mathematics through riddles, Bijaganita covers advanced algebra and Siddhantashiromani astronomical calculation. Several of his works were translated into Persian in the Mughal period.
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around 1200
Indian numerals reach Europe
From the Arab world the numerals reached Europe and parts of Africa by around 1100 CE; around 1200 the Italian mathematician Fibonacci made the case for Europe to adopt them. Arab scholars called them βHindu numeralsβ.
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14th century
Narayana Panditaβs Ganitakaumudi
A massive treatise of mathematics that included important original developments.
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14th century
Madhava and the Kerala School
π KeralaMadhava gave the series expansion for trigonometric functions β a world first β and an exact value of Ο as an infinite series. He and his followers are known as the Kerala School of Astronomy and Mathematics.
π Astronomy
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2nd century BCE β 3rd century CE
Shadow clocks and water clocks
The earliest reference to measuring time by shadows is in Kautilyaβs Arthasastra, which also describes a water clock with water flowing out.
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around 500 CE
Aryabhata and the Aryabhatiya
π Kusumapura (near Patna)A short treatise of mathematics and astronomy. Aryabhata proposed that the Earth spins on its axis, gave the length of the year within minutes of the modern value, estimated the size of the Earth and correctly explained solar and lunar eclipses. His value for one rotation of the Earth is about 23 hours 56 minutes 4.1 seconds.
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Aryabhataβs time
The Ghatika-yantra (sinking-bowl water clock)
Because outflow clocks slowed as the water dropped, a sinking-bowl water clock was developed β first mentioned by Aryabhata. It kept time at monasteries, palaces and town squares, where each sinking of the bowl was announced; the day was divided into 60 ghatis.
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Gupta period
Varahamihiraβs Brihat Samhita
π Ujjayini (Ujjain)An encyclopedic work covering astronomy and astrology, weather forecasting, architecture, town planning and even farming.
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around 530 CE
Time from a stickβs shadow
Varahamihira gave an accurate expression for time in terms of the shadow of a vertical stick.
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11th century
Al-Biruni studies Indian science
π GhazniAl-Biruni learnt Sanskrit and wrote an encyclopaedic survey of India, compiling in mathematics and astronomy what he could gather from the works of Aryabhata, Varahamihira and Brahmagupta.
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Bhaskara IIβs time
Watching the sky in bowls of water
More than 800 years ago, astronomers looked at stars and planets reflected in shallow bowls of water, through tubes set at the right angles, to measure their positions.
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1500
Nilakantha Somayajiβs planetary model
π KeralaA scholar of the Kerala School worked out a planetary model in which Mercury and Venus went round the Sun.
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early 18th century
Jantar Mantar observatory
π Jaipur, RajasthanSome 20 giant masonry instruments for observing the sky with the naked eye.
π©Ί Medicine and life sciences
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7,500β9,000 years ago
The earliest dentistry
π Mehrgarh, BalochistanEleven molar teeth from nine adults were drilled β with flint tips β while the people were alive.
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c. 100 CE; final shape in the Gupta period
Charaka and Sushruta Samhitas
Works on medicine in Sanskrit. Ayurveda has much older roots, but these texts β which deal with cataloguing and diagnosing diseases, among other topics β were compiled and given their final shape during the Gupta period.
β Metals and materials
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c. 1.5 million years ago
Stone hand-axes at Attirampakkam
π Tamil NaduAcheulian hand-axes and cleavers β some of the oldest tools made by early humans in South Asia.
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c. 385,000β172,000 years ago
Smaller, finer stone tools
π Attirampakkam, Tamil NaduA Middle Palaeolithic culture of prepared-core tools, far earlier than once thought.
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Neolithic period
Early cotton
π Mehrgarh, BalochistanCotton fibres preserved inside a copper bead β the first evidence of cotton at Neolithic Mehrgarh.
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Harappan period
Copper and bronze metallurgy
π Harappan citiesThe Harappan civilisation mastered copper and bronze metallurgy β a technology that made its cities possible.
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c. 2500 BCE
Lost-wax bronze casting
π Mohenjo-daroThe βlost-waxβ (cire-perdu) casting process was learnt as long ago as the Indus Valley Culture; the βDancing Girlβ from Mohenjodaro is perhaps the earliest bronze sculpture, datable to 2500 BCE. Tribal craftspeople still use the process today.
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Harappan period
Drilling hard stone beads
π Chanhudaro, Lothal, DholaviraBeads of carnelian and other stones were shaped, ground, polished and drilled; specialised drills have been found at Chanhudaro, Lothal and Dholavira.
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1800β1000 BCE
Iron working in the Ganga plain
π Uttar PradeshIron artefacts, furnaces, tuyeres and slag in layers radiocarbon-dated between 1800 and 1000 BCE.
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Ancient and medieval periods
Wootz steel
π South IndiaThe famed 'wootz': high-carbon steel made in crucibles in South India.
NCERT adds: Wootz steel was among the Indian goods highly sought after in the Mediterranean world. π NCERT Exploring Society: India and Beyond, Grade 8 Part 1, Ch. 4 β
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Ancient period
The rust-resistant iron pillar
π DelhiAn ancient iron pillar that has resisted corrosion for centuries β a puzzle explained by metallurgists.
NCERT adds: Over 1,600 years old, about 8 metres high and more than 6,000 kg, it has barely any rust; its inscription speaks of a king βChandraβ, identified with Chandragupta II. π NCERT Exploring Society: India and Beyond, Grade 7 Part 1, Ch. 7 (The Gupta Era) β
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13thβ17th centuries
Pure zinc by distillation
The production of pure zinc reached its peak, with a special distillation process used for the first time in the world.
π Engineering, water and towns
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Harappan civilization
Planned drainage
π Mohenjo-daro, Harappa and other citiesA planned drainage system in Harappan cities β evidence of town planning.
NCERT adds: House drains first emptied into a sump where solid matter settled, while waste water flowed on into street drains; the drains were covered with loose bricks that could be removed for cleaning. π NCERT Themes in Indian History I, Ch. 1 (Bricks, Beads and Bones) β
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Harappan period
Bricks of a standard ratio
π Harappan settlementsSun-dried or baked, Harappan bricks kept one ratio β length four times and breadth twice the height β and were used at all Harappan settlements, a sign the towns were planned first and then built.
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Harappan civilization
The wheel: terracotta carts
π Harappan sitesTerracotta models of wheeled carts show wheeled transport in Harappan times.
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Harappan period
The dockyard at Lothal
π Lothal, GujaratA huge brick basin at the Harappan settlement of Lothal, which NCERT presents as a dockyard linked to trade.
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c. 3000β1500 BCE
Water management at Dholavira
π Dholavira, GujaratA sophisticated water-management system let a walled city thrive on an arid island.
NCERT adds: NCERT shows a large reservoir cut into the rock at Dholavira, 33 metres long. π NCERT Exploring Society: India and Beyond, Grade 6, Ch. 6 (The Beginnings of Indian Civilisation) β
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Karikalaβs reign
The Kallanai (Grand Anicut)
π Kaveri, below SrirangamA complex water-diversion system built by the Chola king Karikala just downstream of Srirangam island, sending Kaveri waters to the central and southern delta so that more land could be irrigated.
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c. second century CE
Sudarshana lake, a reservoir
π Girnar, GujaratAn artificial reservoir known from a Sanskrit rock inscription recording the achievements of the Shaka ruler Rudradaman, who rebuilt it.
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11th century
Stepwells: Rani-ki-Vav
π Patan, GujaratStepwells stored underground water in India since the 3rd millennium BCE; this one is a masterpiece of the craft.
NCERT adds: In classical times a tradition of stepwells (vavs or baoris) developed in Gujarat and Rajasthan β many of them engineering marvels as well as works of art. π NCERT Exploring Society: India and Beyond, Grade 8 Part 2, Ch. 3 (A Journey through Indian Architecture) β
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1727
Jaipur, a planned city
π JaipurVidyadhar Bhattacharya, appointed by Sawai Jai Singh II, designed the new city on a grid of rectangular blocks, aligned to the cardinal directions, with wide streets, gardens and nine public squares.
πΎ Farming and plants
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from c. 7000 BCE
Farming begins at Mehrgarh
π Mehrgarh, BalochistanOne of the earliest farming villages of the subcontinent, excavated and dated by French archaeologists.
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Early Harappan
A ploughed field and terracotta ploughs
π Kalibangan, RajasthanA field with two sets of furrows at right angles β two crops grown together; terracotta plough models were found in Cholistan and at Banawali.
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c. 600β500 BCE
Paddy transplantation
π Ganga valleyTransplanting rice seedlings spread in the Ganga valley, alongside the growth of towns.
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around the 10th century CE
Surapalaβs Vrikshayurveda
A text of plant science: which plants suit which soils, seed collection and treatment, irrigation by species and season, and natural pest control.
π Language, writing and learning
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Harappan civilization
The Harappan script
π Harappan citiesShort inscriptions on seals β some 375 to 400 signs, the longest about 26 signs long. It is still undeciphered.
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c. 500 BCE
Paniniβs Ashtadhyayi
The Ashtadhyayi of Panini, a work on Sanskrit grammar.
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Mauryan times
Takshashila, a centre of learning
π Takshashila (Taxila)According to Buddhist texts, Kautilya β author of the Arthashastra, βthe science of governance and economicsβ β was a teacher at the world-renowned Takshashila university.
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3rd century BCE
Brahmi: Ashoka's inscriptions
π Across the Mauryan EmpireEdicts carved in the Brahmi script β deciphered by James Prinsep only in 1838.
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3rd century BCE β 13th century CE
Nalanda Mahavihara
π Nalanda, BiharThe most ancient university of the Indian subcontinent, teaching without a break for some 800 years.
NCERT adds: The Palas, like Harsha before them, continued to patronise Nalanda; large monasteries like it were, in effect, the universities of the time. π NCERT Exploring Society: India and Beyond, Grade 7 Part 2, Ch. 3 β
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late 8th century
Vikramashila university
π Banks of the Ganga, BiharFounded by the Pala king Dharmapala, it remained a great centre of learning for more than four centuries, with six colleges, a vast library and nearly 3,000 scholars. Each college had a βscholar gatekeeperβ who set the admission test.
π» Computing and communication
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September 1556
The first printing press
π Old GoaSet up by Jesuit missionaries at the Colegio de SΓ£o Paulo β the first printing press in India.
π‘ Ideas and texts
NCERT describes these without giving a date, so they are not placed on the timeline.
Acharya Kanad first spoke of the Parmanu: matter made of tiny, indivisible, eternal particles. The idea is in his Vaisheshika Sutras.
π NCERT Curiosity (Science), Grade 8, Ch. 7 (Particulate Nature of Matter) βMany Indian astronomical texts give calculations to predict eclipses; the best known is the Surya Siddhanta, written in rhythmic Sanskrit shlokas. The Indian National Calendar adopted in 1956 follows its general principles.
π NCERT Curiosity (Science), Grade 7, Ch. 12 (Earth, Moon, and the Sun) βLong before modern vaccines, India had variolation: material from a smallpox sore was scratched into the skin to cause a mild infection and build immunity. Its practitioners were known as teekedaars.
π NCERT Curiosity (Science), Grade 8, Ch. 3 βMishraloha was a mixture of metals with properties of its own. The Charaka Samhita, Susruta Samhita and Rasaratna Samucchaya mention alloys in medicine β bronze (kamsya) was 4 parts copper to 1 part tin. The Rasaratna Samucchaya says crucibles were made of clay and iron.
π NCERT Curiosity (Science), Grade 8, Ch. 8 βThe Vedas, including the Atharvaveda, use the word βkrimiβ for tiny entities, both drishya (visible) and adrishya (invisible), and mention their beneficial and harmful effects.
π NCERT Curiosity (Science), Grade 8, Ch. 2 (The Invisible Living World) βThe Vrikshayurveda advocates feeding the soil continuously with organic manure such as kunapa jala, a liquid fertiliser made by fermenting animal and plant waste.
π NCERT Curiosity (Science), Grade 8, Ch. 12 (How Nature Works in Harmony) βHow we check: everything on this page comes from NCERT textbooks β Exploring Society, Ganita Prakash, Curiosity, Themes in Indian History and An Introduction to Indian Art β or from the sources of the Tools & Technology milestones, and our build fails unless the key phrases are found in the source itself. Where NCERT gives no date, neither do we.