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Saturday, October 20, 2018

History of science and technology in China

From Wikipedia, the free encyclopedia

Instructions for making astronomical instruments from the time of the Qing Dynasty.

Ancient Chinese scientists and engineers made significant scientific innovations, findings and technological advances across various scientific disciplines including the natural sciences, engineering, medicine, military technology, mathematics, geology and astronomy.

Among the earliest inventions were the abacus, the "shadow clock," and the first items such as Kongming lanterns. The Four Great Inventions,the compass, gunpowder, papermaking, and printing – were among the most important technological advances, only known to Europe by the end of the Middle Ages 1000 years later. The Tang Dynasty (AD 618–906) in particular was a time of great innovation. A good deal of exchange occurred between Western and Chinese discoveries up to the Qing Dynasty.

The Jesuit China missions of the 16th and 17th centuries introduced Western science and astronomy, then undergoing its own revolution, to China, and knowledge of Chinese technology was brought to Europe. In the 19th and 20th centuries the introduction of Western technology was a major factor in the modernization of China. Much of the early Western work in the history of science in China was done by Joseph Needham.

Mo Di and the School of Names

The Warring States period began 2500 years ago at the time of the invention of the crossbow. Needham notes that the invention of the crossbow "far outstripped the progress in defensive armor", which made the wearing of armor useless to the princes and dukes of the states. At this time, there were also many nascent schools of thought in China — the Hundred Schools of Thought (諸子百家), scattered among many polities. The schools served as communities which advised the rulers of these states. Mo Di (墨翟 Mozi, 470 BCE–ca. 391 BCE) introduced concepts useful to one of those rulers, such as defensive fortification. One of these concepts, fa (法 principle or method) was extended by the School of Names (名家 Ming jia, ming=name), which began a systematic exploration of logic. The development of a school of logic was cut short by the defeat of Mohism's political sponsors by the Qin Dynasty, and the subsumption of fa as law rather than method by the Legalists (法家 Fa jia).
Needham further notes that the Han Dynasty, which conquered the short-lived Qin, were made aware of the need for law by Lu Chia and by Shu-Sun Thung, as defined by the scholars, rather than the generals.
You conquered the empire on horseback, but from horseback you will never succeed in ruling it.
— Lu Chia
Derived from Taoist philosophy, one of the newest longstanding contributions of the ancient Chinese are in Traditional Chinese medicine, including acupuncture and herbal medicine. The practice of acupuncture can be traced back as far as the 1st millennium BC and some scientists believe that there is evidence that practices similar to acupuncture were used in Eurasia during the early Bronze Age.

Using shadow clocks and the abacus (both invented in the ancient Near East before spreading to China), the Chinese were able to record observations, documenting the first recorded solar eclipse in 2137 BC, and making the first recording of any planetary grouping in 500 BC. These claims, however, are highly disputed and rely on much supposition. The Book of Silk was the first definitive atlas of comets, written c. 400 BC. It listed 29 comets (referred to as sweeping stars) that appeared over a period of about 300 years, with renderings of comets describing an event its appearance corresponded to.

In architecture, the pinnacle of Chinese technology manifested itself in the Great Wall of China, under the first Chinese Emperor Qin Shi Huang between 220 and 200 BC. Typical Chinese architecture changed little from the succeeding Han Dynasty until the 19th century. The Qin Dynasty also developed the crossbow, which later became the mainstream weapon in Europe. Several remains of crossbows have been found among the soldiers of the Terracotta Army in the tomb of Qin Shi Huang.

Han Dynasty

Remains of a Chinese crossbow, 2nd century BC.

The Eastern Han Dynasty scholar and astronomer Zhang Heng (78–139 AD) invented the first water-powered rotating armillary sphere (the first armillary sphere having been invented by the Greek Eratosthenes), and catalogued 2,500 stars and over 100 constellations. In 132, he invented the first seismological detector, called the "Houfeng Didong Yi" ("Instrument for inquiring into the wind and the shaking of the earth"). According to the History of Later Han Dynasty (25–220 AD), this seismograph was an urn-like instrument, which would drop one of eight balls to indicate when and in which direction an earthquake had occurred. On June 13, 2005, Chinese seismologists announced that they had created a replica of the instrument.

The mechanical engineer Ma Jun (c.200–265 AD) was another impressive figure from ancient China. Ma Jun improved the design of the silk loom, designed mechanical chain pumps to irrigate palatial gardens, and created a large and intricate mechanical puppet theatre for Emperor Ming of Wei, which was operated by a large hidden waterwheel. However, Ma Jun's most impressive invention was the south-pointing chariot, a complex mechanical device that acted as a mechanical compass vehicle. It incorporated the use of a differential gear in order to apply equal amount of torque to wheels rotating at different speeds, a device that is found in all modern automobiles.

Sliding calipers were invented in China almost 2,000 years ago. The Chinese civilization was the earliest civilization to experiment successfully with aviation, with the kite and Kongming lantern (proto Hot air balloon) being the first flying machines.

"Four Great Inventions"

The intricate frontispiece of the Diamond Sutra from Tang Dynasty China, 868 AD (British Library)

The "Four Great Inventions" (simplified Chinese: 四大发明; traditional Chinese: 四大發明; pinyin: sì dà fāmíng) are the compass, gunpowder, papermaking and printing. Paper and printing were developed first. Printing was recorded in China in the Tang Dynasty, although the earliest surviving examples of printed cloth patterns date to before 220. Pin-pointing the development of the compass can be difficult: the magnetic attraction of a needle is attested by the Louen-heng, composed between AD 20 and 100, although the first undisputed magnetized needles in Chinese literature appear in 1086.

By AD 300, Ge Hong, an alchemist of the Jin Dynasty, conclusively recorded the chemical reactions caused when saltpetre, pine resin and charcoal were heated together, in Book of the Master of the Preservations of Solidarity. Another early record of gunpowder, a Chinese book from c. 850 AD, indicates:
"Some have heated together sulfur, realgar and saltpeter with honey; smoke and flames result, so that their hands and faces have been burnt, and even the whole house where they were working burned down."
These four discoveries had an enormous impact on the development of Chinese civilization and a far-ranging global impact. Gunpowder, for example, spread to the Arabs in the 13th century and thence to Europe. According to English philosopher Francis Bacon, writing in Novum Organum:
Printing, gunpowder and the compass: These three have changed the whole face and state of things throughout the world; the first in literature, the second in warfare, the third in navigation; whence have followed innumerable changes, in so much that no empire, no sect, no star seems to have exerted greater power and influence in human affairs than these mechanical discoveries.
One of the most important military treatises of all Chinese history was the Huo Long Jing written by Jiao Yu in the 14th century. For gunpowder weapons, it outlined the use of fire arrows and rockets, fire lances and firearms, land mines and naval mines, bombards and cannons, two stage rockets, along with different compositions of gunpowder, including 'magic gunpowder', 'poisonous gunpowder', and 'blinding and burning gunpowder' (refer to his article).

For the 11th century invention of ceramic movable type printing by Bi Sheng (990-1051), it was enhanced by the wooden movable type of Wang Zhen in 1298 and the bronze metal movable type of Hua Sui in 1490.

China's scientific revolution

Ships of the world in 1460 (Fra Mauro map). Chinese junks are described as very large, three or four-masted ships.

Among the engineering accomplishments of early China were matches, dry docks, the double-action piston pump, cast iron, the iron plough, the horse collar, the multi-tube seed drill, the wheelbarrow, the suspension bridge, the parachute, natural gas as fuel, the raised-relief map, the propeller, the sluice gate, and the pound lock. The Tang Dynasty (AD 618–906) and Song Dynasty (AD 960–1279) in particular were periods of great innovation.

In the 7th century, book-printing was developed in China, Korea and Japan, using delicate hand-carved wooden blocks to print individual pages. The 9th century Diamond Sutra is the earliest known printed document. Movable type was also used in China for a time, but was abandoned because of the number of characters needed; it would not be until Johannes Gutenberg that the technique was reinvented in a suitable environment.

In addition to gunpowder, the Chinese also developed improved delivery systems for the Byzantine weapon of Greek fire, Meng Huo You and Pen Huo Qi first used in China c. 900. Chinese illustrations were more realistic than in Byzantine manuscripts, and detailed accounts from 1044 recommending its use on city walls and ramparts show the brass container as fitted with a horizontal pump, and a nozzle of small diameter. The records of a battle on the Yangtze near Nanjing in 975 offer an insight into the dangers of the weapon, as a change of wind direction blew the fire back onto the Song forces.

Song Dynasty

The Song Dynasty (960–1279) brought a new stability for China after a century of civil war, and started a new area of modernisation by encouraging examinations and meritocracy. The first Song Emperor created political institutions that allowed a great deal of freedom of discourse and thought, which facilitated the growth of scientific advance, economic reforms, and achievements in arts and literature. Trade flourished both within China and overseas, and the encouragement of technology allowed the mints at Kaifeng and Hangzhou to gradually increase in production. In 1080, the mints of Emperor Shenzong had produced 5 billion coins (roughly 50 per Chinese citizen), and the first banknotes were produced in 1023. These coins were so durable that they would still be in use 700 years later, in the 18th century.

There were many famous inventors and early scientists in the Song Dynasty period. The statesman Shen Kuo is best known for his book known as the Dream Pool Essays (1088 AD). In it, he wrote of use for a drydock to repair boats, the navigational magnetic compass, and the discovery of the concept of true north (with magnetic declination towards the North Pole). Shen Kuo also devised a geological theory for land formation, or geomorphology, and theorized that there was climate change in geological regions over an enormous span of time.

The equally talented statesman Su Song was best known for his engineering project of the Astronomical Clock Tower of Kaifeng, by 1088 AD. The clock tower was driven by a rotating waterwheel and escapement mechanism. Crowning the top of the clock tower was the large bronze, mechanically-driven, rotating armillary sphere. In 1070, Su Song also compiled the Ben Cao Tu Jing (Illustrated Pharmacopoeia, original source material from 1058–1061 AD) with a team of scholars. This pharmaceutical treatise covered a wide range of other related subjects, including botany, zoology, mineralogy, and metallurgy.

Chinese astronomers were the first to record observations of a supernova, the first being the SN 185, recorded during the Han Dynasty. Chinese astronomers made two more notable supernova observations during the Song Dynasty: the SN 1006, the brightest recorded supernova in history; and the SN 1054, making the Crab Nebula the first astronomical object recognized as being connected to a supernova explosion.

Archaeology

During the early half of the Song Dynasty (960–1279), the study of archaeology developed out of the antiquarian interests of the educated gentry and their desire to revive the use of ancient vessels in state rituals and ceremonies. This and the belief that ancient vessels were products of 'sages' and not common people was criticized by Shen Kuo, who took an interdisciplinary approach to archaeology, incorporating his archaeological findings into studies on metallurgy, optics, astronomy, geometry, and ancient music measures. His contemporary Ouyang Xiu (1007–1072) compiled an analytical catalogue of ancient rubbings on stone and bronze, which Patricia B. Ebrey says pioneered ideas in early epigraphy and archaeology. In accordance with the beliefs of the later Leopold von Ranke (1795–1886), some Song gentry—such as Zhao Mingcheng (1081–1129)—supported the primacy of contemporaneous archaeological finds of ancient inscriptions over historical works written after the fact, which they contested to be unreliable in regard to the former evidence. Hong Mai (1123–1202) used ancient Han Dynasty era vessels to debunk what he found to be fallacious descriptions of Han vessels in the Bogutu archaeological catalogue compiled during the latter half of Huizong's reign (1100–1125).

Geology and climatology

In addition to his studies in meteorology, astronomy, and archaeology mentioned above, Shen Kuo also made hypotheses in regards to geology and climatology in his Dream Pool Essays of 1088, specifically his claims regarding geomorphology and climate change. Shen believed that land was reshaped over time due to perpetual erosion, uplift, and deposition of silt, and cited his observance of horizontal strata of fossils embedded in a cliffside at Taihang as evidence that the area was once the location of an ancient seashore that had shifted hundreds of miles east over an enormous span of time. Shen also wrote that since petrified bamboos were found underground in a dry northern climate zone where they had never been known to grow, climates naturally shifted geographically over time.

Mongol transmission

Mongol rule under the Yuan Dynasty saw technological advances from an economic perspective, with the first mass production of paper banknotes by Kublai Khan in the 13th century. Numerous contacts between Europe and the Mongols occurred in the 13th century, particularly through the unstable Franco-Mongol alliance. Chinese corps, expert in siege warfare, formed an integral part of the Mongol armies campaigning in the West. In 1259-1260 military alliance of the Franks knights of the ruler of Antioch, Bohemond VI and his father-in-law Hetoum I with the Mongols under Hulagu, in which they fought together for the conquests of Muslim Syria, taking together the city of Aleppo, and later Damascus. William of Rubruck, an ambassador to the Mongols in 1254-1255, a personal friend of Roger Bacon, is also often designated as a possible intermediary in the transmission of gunpowder know-how between the East and the West. The compass is often said to have been introduced by the Master of the Knights Templar Pierre de Montaigu between 1219 and 1223, from one of his travels to visit the Mongols in Persia.

Chinese and Arabic astronomy intermingled under Mongol rule. Muslim astronomers worked in the Chinese Astronomical Bureau established by Kublai Khan, while some Chinese astronomers also worked at the Persian Maragha observatory. Before this, in ancient times, Indian astronomers had lent their expertise to the Chinese court.

Theory and hypothesis

A 1726 illustration of Haidao Suanjing, written by Liu Hui in the 3rd century.

As Toby E. Huff notes, pre-modern Chinese science developed precariously without solid scientific theory, while there was a lacking of consistent systemic treatment in comparison to contemporaneous European works such as the Concordance and Discordant Canons by Gratian of Bologna (fl. 12th century). This drawback to Chinese science was lamented even by the mathematician Yang Hui (1238–1298), who criticized earlier mathematicians such as Li Chunfeng (602–670) who were content with using methods without working out their theoretical origins or principle, stating:
The men of old changed the name of their methods from problem to problem, so that as no specific explanation was given, there is no way of telling their theoretical origin or basis.
Despite this, Chinese thinkers of the Middle Ages proposed some hypotheses which are in accordance with modern principles of science. Yang Hui provided theoretical proof for the proposition that the complements of the parallelograms which are about the diameter of any given parallelogram are equal to one another. Sun Sikong (1015–1076) proposed the idea that rainbows were the result of the contact between sunlight and moisture in the air, while Shen Kuo (1031–1095) expanded upon this with description of atmospheric refraction. Shen believed that rays of sunlight refracted before reaching the surface of the earth, hence the appearance of the observed sun from earth did not match its exact location. Coinciding with the astronomical work of his colleague Wei Pu, Shen and Wei realized that the old calculation technique for the mean sun was inaccurate compared to the apparent sun, since the latter was ahead of it in the accelerated phase of motion, and behind it in the retarded phase.[45] Shen supported and expanded upon beliefs earlier proposed by Han Dynasty (202 BCE–202 CE) scholars such as Jing Fang (78–37 BCE) and Zhang Heng (78–139 CE) that lunar eclipse occurs when the earth obstructs the sunlight traveling towards the moon, a solar eclipse is the moon's obstruction of sunlight reaching earth, the moon is spherical like a ball and not flat like a disc, and moonlight is merely sunlight reflected from the moon's surface. Shen also explained that the observance of a full moon occurred when the sun's light was slanting at a certain degree and that crescent phases of the moon proved that the moon was spherical, using a metaphor of observing different angles of a silver ball with white powder thrown onto one side. Although the Chinese accepted the idea of spherical-shaped heavenly bodies, the concept of a spherical earth (as opposed to a flat earth) was not accepted in Chinese thought until the works of Italian Jesuit Matteo Ricci (1552–1610) and Chinese astronomer Xu Guangqi (1562–1633) in the early 17th century.

Pharmacology

There were noted advances in traditional Chinese medicine during the Middle Ages. Emperor Gaozong (reigned 649–683) of the Tang Dynasty (618–907) commissioned the scholarly compilation of a materia medica in 657 that documented 833 medicinal substances taken from stones, minerals, metals, plants, herbs, animals, vegetables, fruits, and cereal crops. In his Bencao Tujing ('Illustrated Pharmacopoeia'), the scholar-official Su Song (1020–1101) not only systematically categorized herbs and minerals according to their pharmaceutical uses, but he also took an interest in zoology. For example, Su made systematic descriptions of animal species and the environmental regions they could be found, such as the freshwater crab Eriocher sinensis found in the Huai River running through Anhui, in waterways near the capital city, as well as reservoirs and marshes of Hebei.

Muhammad ibn Zakariya al-Razi in 896, mentions the popular introduction of various Chinese herbs and aloes in Baghdad.

Horology and clockworks

Although the Bencao Tujing was an important pharmaceutical work of the age, Su Song is perhaps better known for his work in horology. His book Xinyi Xiangfayao (新儀象法要; lit. 'Essentials of a New Method for Mechanizing the Rotation of an Armillary Sphere and a Celestial Globe') documented the intricate mechanics of his astronomical clock tower in Kaifeng. This included the use of an escapement mechanism and world's first known chain drive to power the rotating armillary sphere crowning the top as well as the 133 clock jack figurines positioned on a rotating wheel that sounded the hours by banging drums, clashing gongs, striking bells, and holding plaques with special announcements appearing from open-and-close shutter windows. While it had been Zhang Heng who applied the first motive power to the armillary sphere via hydraulics in 125 CE, it was Yi Xing (683–727) in 725 CE who first applied an escapement mechanism to a water-powered celestial globe and striking clock. The early Song Dynasty horologist Zhang Sixun (fl. late 10th century) employed liquid mercury in his astronomical clock because there were complaints that water would freeze too easily in the clepsydra tanks during winter.

The elephant clock in a manuscript by Al-Jazari (1206 AD) from The Book of Knowledge of Ingenious Mechanical Devices.

Al-Jazari (1136–1206), a Muslim engineer and inventor of various clocks, including the Elephant clock, wrote: "[T]he elephant represents the Indian and African cultures, the two dragons represents Chinese culture, the phoenix represents Persian culture, the water work represents ancient Greek culture, and the turban represents Islamic culture".

Magnetism and metallurgy

Shen Kuo's written work of 1088 also contains the first written description of the magnetic needle compass, the first description in China of experiments with camera obscura, the invention of movable type printing by the artisan Bi Sheng (990–1051), a method of repeated forging of cast iron under a cold blast similar to the modern Bessemer process, and the mathematical basis for spherical trigonometry that would later be mastered by the astronomer and engineer Guo Shoujing (1231–1316). While using a sighting tube of improved width to correct the position of the pole star (which had shifted over the centuries), Shen discovered the concept of true north and magnetic declination towards the North Magnetic Pole, a concept which would aid navigators in the years to come.

In addition to the method similar to the Bessemer process mentioned above, there were other notable advancements in Chinese metallurgy during the Middle Ages. During the 11th century, the growth of the iron industry caused vast deforestation due to the use of charcoal in the smelting process. To remedy the problem of deforestation, the Song Chinese discovered how to produce coke from bituminous coal as a substitute for charcoal. Although hydraulic-powered bellows for heating the blast furnace had been written of since Du Shi's (d. 38) invention of the 1st century CE, the first known drawn and printed illustration of it in operation is found in a book written in 1313 by Wang Zhen (fl. 1290–1333).

Mathematics

Qin Jiushao (c. 1202–1261) was the first to introduce the zero symbol into Chinese mathematics. Before this innovation, blank spaces were used instead of zeros in the system of counting rods. Pascal's triangle was first illustrated in China by Yang Hui in his book Xiangjie Jiuzhang Suanfa (详解九章算法), although it was described earlier around 1100 by Jia Xian. Although the Introduction to Computational Studies (算学启蒙) written by Zhu Shijie (fl. 13th century) in 1299 contained nothing new in Chinese algebra, it had a great impact on the development of Japanese mathematics.

Alchemy and Taoism

Stoneware bombs, known in Japanese as Tetsuhau (iron bomb), or in Chinese as Zhentianlei (thunder crash bomb), excavated from the Takashima shipwreck, October 2011. Excavated bombs contain a 3-6cm opening at the top where the fuse was placed. Once the fuse was lit, the bomb was thrown either by hand or catapult. According to the Mōko Shūrai Ekotoba scroll, these bombs made a large noise and emitted bright fire upon explosion. Prior to the shipwreck's discovery, observers believed the bombs depicted in the scroll were a later addition.

In their pursuit for an elixir of life and desire to create gold from various mixtures of materials, Taoists became heavily associated with alchemy. Joseph Needham labeled their pursuits as proto-scientific rather than merely pseudoscience. Fairbank and Goldman write that the futile experiments of Chinese alchemists did lead to the discovery of new metal alloys, porcelain types, and dyes. However, Nathan Sivin discounts such a close connection between Taoism and alchemy, which some sinologists have asserted, stating that alchemy was more prevalent in the secular sphere and practiced by laymen.

Experimentation with various materials and ingredients in China during the middle period led to the discovery of many ointments, creams, and other mixtures with practical uses. In a 9th-century Arab work Kitāb al-Khawāss al Kabīr, there are numerous products listed that were native to China, including waterproof and dust-repelling cream or varnish for clothes and weapons, a Chinese lacquer, varnish, or cream that protected leather items, a completely fire-proof cement for glass and porcelain, recipes for Chinese and Indian ink, a waterproof cream for the silk garments of underwater divers, and a cream specifically used for polishing mirrors.

Gunpowder warfare

The significant change that distinguished Medieval warfare to early Modern warfare was the use of gunpowder weaponry in battle. A 10th-century silken banner from Dunhuang portrays the first artistic depiction of a fire lance, a prototype of the gun. The Wujing Zongyao military manuscript of 1044 listed the first known written formulas for gunpowder, meant for light-weight bombs lobbed from catapults or thrown down from defenders behind city walls. By the 13th century, the iron-cased bomb shell, hand cannon, land mine, and rocket were developed. As evidenced by the Huolongjing of Jiao Yu and Liu Bowen, by the 14th century the Chinese had developed the heavy cannon, hollow and gunpowder-packed exploding cannonballs, the two-stage rocket with a booster rocket, the naval mine and wheellock mechanism to ignite trains of fuses.

Jesuit activity in China

Jesuits in China.

The Jesuit China missions of the 16th and 17th centuries introduced Western science and astronomy, then undergoing its own revolution, to China. One modern historian writes that in late Ming courts, the Jesuits were "regarded as impressive especially for their knowledge of astronomy, calendar-making, mathematics, hydraulics, and geography." The Society of Jesus introduced, according to Thomas Woods, "a substantial body of scientific knowledge and a vast array of mental tools for understanding the physical universe, including the Euclidean geometry that made planetary motion comprehensible." Another expert quoted by Woods said the scientific revolution brought by the Jesuits coincided with a time when science was at a very low level in China:
[The Jesuits] made efforts to translate western mathematical and astronomical works into Chinese and aroused the interest of Chinese scholars in these sciences. They made very extensive astronomical observation and carried out the first modern cartographic work in China. They also learned to appreciate the scientific achievements of this ancient culture and made them known in Europe. Through their correspondence European scientists first learned about the Chinese science and culture.
Conversely, the Jesuits were very active in transmitting Chinese knowledge to Europe. Confucius's works were translated into European languages through the agency of Jesuit scholars stationned in China. Matteo Ricci started to report on the thoughts of Confucius, and Father Prospero Intorcetta published the life and works of Confucius into Latin in 1687. It is thought that such works had considerable importance on European thinkers of the period, particularly among the Deists and other philosophical groups of the Enlightenment who were interested by the integration of the system of morality of Confucius into Christianity.

The followers of the French physiocrat François Quesnay habitually referred to him as "the Confucius of Europe", and he personally identified himself with the Chinese sage. The doctrine and even the name of "Laissez-faire" may have been inspired by the Chinese concept of Wu wei. However, the economic insights of ancient Chinese political thought had otherwise little impact outside China in later centuries. Goethe, was known as "the Confucius of Weimar".

Scientific and technological stagnation

One question that has been the subject of debate among historians has been why China did not develop a scientific revolution and why Chinese technology fell behind that of Europe. Many hypotheses have been proposed ranging from the cultural to the political and economic. John K. Fairbank, for example, argued that the Chinese political system was hostile to scientific progress. As for Needham, he wrote that cultural factors prevented traditional Chinese achievements from developing into what could be called "science." It was the religious and philosophical framework of the Chinese intellectuals which made them unable to believe in the ideas of laws of nature:
It was not that there was no order in nature for the Chinese, but rather that it was not an order ordained by a rational personal being, and hence there was no conviction that rational personal beings would be able to spell out in their lesser earthly languages the divine code of laws which he had decreed aforetime. The Taoists, indeed, would have scorned such an idea as being too naïve for the subtlety and complexity of the universe as they intuited it.
Another prominent historian of science, Nathan Sivin, has argued that China indeed had a scientific revolution in the 17th century but it's just that we are still not able to really understand the scientific revolution that took place in China. Sivin suggests that we need to look at the scientific development in China on its own terms.

There are also questions about the philosophy behind traditional Chinese medicine, which, derived partly from Taoist philosophy, reflects the classical Chinese belief that individual human experiences express causative principles effective in the environment at all scales. Because its theory predates use of the scientific method, it has received various criticisms based on scientific thinking. Philosopher Robert Todd Carroll, a member of the Skeptics Society, deemed acupuncture a pseudoscience because it "confuse(s) metaphysical claims with empirical claims".

More recent historians have questioned political and cultural explanations and have put greater focus on economic causes. Mark Elvin's high level equilibrium trap is one well-known example of this line of thought. It argues that the Chinese population was large enough, workers cheap enough, and agrarian productivity high enough to not require mechanization: thousands of Chinese workers were perfectly able to quickly perform any needed task. Other events such as Haijin, the Opium Wars and the resulting hate of European influence prevented China from undergoing an Industrial Revolution; copying Europe's progress on a large scale would be impossible for a lengthy period of time. Political instability under Cixi rule (opposition and frequent oscillation between modernists and conservatives), the Republican wars (1911–1933), the Sino-Japanese War (1933–1945), the Communist/Nationalist War (1945–1949) as well as the later Cultural Revolution isolated China at the most critical times. Kenneth Pomeranz has made the argument that the substantial resources taken from the New World to Europe made the crucial difference between European and Chinese development.

In his book Guns, Germs, and Steel, Jared Diamond postulates that the lack of geographic barriers within much of China – essentially a wide plain with two large navigable rivers and a relatively smooth coastline – led to a single government without competition. At the whim of a ruler who disliked new inventions, technology could be stifled for half a century or more. In contrast, Europe's barriers of the Pyrenees, the Alps, and the various defensible peninsulas (Denmark, Scandinavia, Italy, Greece, etc.) and islands (Britain, Ireland, Sicily, etc.) led to smaller countries in constant competition with each other. If a ruler chose to ignore a scientific advancement (especially a military or economic one), his more-advanced neighbors would soon usurp his throne. This explanation, however, ignores the fact that China had been politically fragmented in the past, and was thus not inherently disposed to political unification.

The Republic of China (1912–49)

The Republican period (1911-1949) saw the introduction in earnest of modern science to China. Large numbers of Chinese students studied abroad in Japan and in Europe and the US. Many returned to help teach and to found numerous schools and universities. Among them were numerous outstanding figures, including Cai Yuanpei, Hu Shi, Weng Wenhao, Ding Wenjiang, Fu Ssu-nien, and many others. As a result, there was a tremendous growth of modern science in China. As the Communist Party took over China's mainland in 1949, some of these Chinese scientists and institutions moved to Taiwan. The central science academy, Academia Sinica, also moved there.

People's Republic of China

After the establishment of the People's Republic in 1949, China reorganized its science establishment along Soviet lines. Although the country regressed scientifically as a result of government policies which led to famine during the Great Leap Forward and political chaos during the Cultural Revolution, scientific research in nuclear weapons and satellite launching still gained great success. From 1975, science and technology was one of the Four Modernizations, and its high-speed development was declared essential to all national economic development by Deng Xiaoping. Other civilian technologies such as superconductivity and high-yield hybrid rice led to new developments due to the application of science to industry and foreign technology transfer.

As the People's Republic of China becomes better connected to the global economy, the government has placed more emphasis on science and technology. This has led to increases in funding, improved scientific structure, and more money for research. These factors have led to advancements in agriculture, medicine, genetics, and global change. In 2003, the Chinese space program allowed China to become the third country to send humans into space, and ambition to put a man on mars by 2030. In the 2000s and 2010s, China became a top scientific and industrial power in more advanced fields such as super computing, artificial intelligence, bullet trains, aeronautics, nuclear physics researches and other fields.

In 2016, China became the country with the highest science output, as measured in publications. While the US had been the biggest producer of scientific studies until then, China published 426,000 studies in 2016 while the US published 409,000. However, the numbers are somewhat relative, as it also depends how authorship on international collaborations is counted (e.g. if one paper is counted per person or whether authorship is split among authors).

History of science and technology in the Indian subcontinent

From Wikipedia, the free encyclopedia
 
The history of science and technology in the Indian Subcontinent begins with prehistoric human activity in the Indus Valley Civilization to early states and empires. Following independence, science and technology in the Republic of India has included automobile engineering, information technology, communications as well as space, polar, and nuclear sciences.

Prehistory

Hand-propelled wheel cart, Indus Valley Civilization (3300–1300 BCE). Housed at the National Museum, New Delhi.

By 5500 BCE a number of sites similar to Mehrgarh had appeared, forming the basis of later chalcolithic cultures. The inhabitants of these sites maintained trading relations with Near East and Central Asia.

Irrigation was developed in the Indus Valley Civilization by around 4500 BCE. The size and prosperity of the Indus civilization grew as a result of this innovation, which eventually led to more planned settlements making use of drainage and sewerage. Sophisticated irrigation and water storage systems were developed by the Indus Valley Civilization, including artificial reservoirs at Girnar dated to 3000 BCE, and an early canal irrigation system from c. 2600 BCE. Cotton was cultivated in the region by the 5th–4th millennia BCE. Sugarcane was originally from tropical South and Southeast Asia. Different species likely originated in different locations with S. barberi originating in India, and S. edule and S. officinarum coming from New Guinea.

The inhabitants of the Indus valley developed a system of standardization, using weights and measures, evident by the excavations made at the Indus valley sites. This technical standardization enabled gauging devices to be effectively used in angular measurement and measurement for construction. Calibration was also found in measuring devices along with multiple subdivisions in case of some devices. One of the earliest known docks is at Lothal (2400 BCE), located away from the main current to avoid deposition of silt. Modern oceanographers have observed that the Harappans must have possessed knowledge relating to tides in order to build such a dock on the ever-shifting course of the Sabarmati, as well as exemplary hydrography and maritime engineering.

Excavations at Balakot (c. 2500–1900 BCE), present day Pakistan, have yielded evidence of an early furnace. The furnace was most likely used for the manufacturing of ceramic objects. Ovens, dating back to the civilization's mature phase (c. 2500–1900 BCE), were also excavated at Balakot. The Kalibangan archeological site further yields evidence of potshaped hearths, which at one site have been found both on ground and underground. Kilns with fire and kiln chambers have also been found at the Kalibangan site.

View of the Ashokan Pillar at Vaishali. One of the edicts of Ashoka (272—231 BCE) reads: "Everywhere King Piyadasi (Ashoka) erected two kinds of hospitals, hospitals for people and hospitals for animals. Where there were no healing herbs for people and animals, he ordered that they be bought and planted."

Based on archaeological and textual evidence, Joseph E. Schwartzberg (2008)—a University of Minnesota professor emeritus of geography—traces the origins of Indian cartography to the Indus Valley Civilization (c. 2500–1900 BCE). The use of large scale constructional plans, cosmological drawings, and cartographic material was known in India with some regularity since the Vedic period (2nd - 1st millennium BCE). Climatic conditions were responsible for the destruction of most of the evidence, however, a number of excavated surveying instruments and measuring rods have yielded convincing evidence of early cartographic activity. Schwartzberg (2008)—on the subject of surviving maps—further holds that: 'Though not numerous, a number of map-like graffiti appear among the thousands of Stone Age Indian cave paintings; and at least one complex Mesolithic diagram is believed to be a representation of the cosmos.'

Archeological evidence of an animal-drawn plough dates back to 2500 BCE in the Indus Valley Civilization. The earliest available swords of copper discovered from the Harappan sites date back to 2300 BCE. Swords have been recovered in archaeological findings throughout the GangesJamuna Doab region of India, consisting of bronze but more commonly copper.

Early kingdoms

Ink drawing of Ganesha under an umbrella (early 19th century). Carbon pigment Ink, called masi, and popularly known as India ink was an admixture of several chemical components, has been used in India since at least the 4th century BCE. The practice of writing with ink and a sharp pointed needle was common in early South India. Several Jain sutras in India were compiled in Carbon pigment Ink.
 
The Hindu-Arabic numeral system. The inscriptions on the edicts of Ashoka (1st millennium BCE) display this number system being used by the Imperial Mauryas.

The religious texts of the Vedic Period provide evidence for the use of large numbers. By the time of the last Veda, the Yajurvedasaṃhitā (1200-900 BCE), numbers as high as 10^{{12}} were being included in the texts. For example, the mantra (sacrificial formula) at the end of the annahoma ("food-oblation rite") performed during the aśvamedha ("an allegory for a horse sacrifice"), and uttered just before-, during-, and just after sunrise, invokes powers of ten from a hundred to a trillion. The Satapatha Brahmana (9th century BCE) contains rules for ritual geometric constructions that are similar to the Sulba Sutras.

Baudhayana (c. 8th century BCE) composed the Baudhayana Sulba Sutra, which contains examples of simple Pythagorean triples, such as: (3,4,5), (5,12,13), (8,15,17), (7,24,25), and (12,35,37) as well as a statement of the Pythagorean theorem for the sides of a square: "The rope which is stretched across the diagonal of a square produces an area double the size of the original square." It also contains the general statement of the Pythagorean theorem (for the sides of a rectangle): "The rope stretched along the length of the diagonal of a rectangle makes an area which the vertical and horizontal sides make together." Baudhayana gives a formula for the square root of two. Mesopotamian influence at this stage is considered likely.

The earliest Indian astronomical text—named Vedānga Jyotiṣa— attributed to Lagadha, is considered one of the oldest astronomical texts, dating from 1400–1200 BCE (with the extant form possibly from 700–600 BCE), it details several astronomical attributes generally applied for timing social and religious events. It also details astronomical calculations, calendrical studies, and establishes rules for empirical observation. Since the Vedānga Jyotiṣa is a religious text, it has connections with Indian astrology and details several important aspects of the time and seasons, including lunar months, solar months, and their adjustment by a lunar leap month of Adhikamāsa. Ritus and Yugas are also described. Tripathi (2008) holds that "Twenty-seven constellations, eclipses, seven planets, and twelve signs of the zodiac were also known at that time."

The Egyptian Papyrus of Kahun (1900 BCE) and literature of the Vedic period in India offer early records of veterinary medicine. Kearns & Nash (2008) state that mention of leprosy is described in the medical treatise Sushruta Samhita (6th century BCE). The Sushruta Samhita an Ayurvedic text contains 184 chapters and description of 1120 illnesses, 700 medicinal plants, a detailed study on Anatomy, 64 preparations from mineral sources and 57 preparations based on animal sources. However, The Oxford Illustrated Companion to Medicine holds that the mention of leprosy, as well as ritualistic cures for it, were described in the Hindu religious book Atharva-veda, written in 1500–1200 BCE.

Cataract surgery was known to the physician Sushruta (6th century BCE). Traditional cataract surgery was performed with a special tool called the Jabamukhi Salaka, a curved needle used to loosen the lens and push the cataract out of the field of vision. The eye would later be soaked with warm butter and then bandaged. Though this method was successful, Susruta cautioned that it should only be used when necessary. The removal of cataract by surgery was also introduced into China from India.

During the 5th century BCE, the scholar Pāṇini had made several discoveries in the fields of phonetics, phonology, and morphology. Pāṇini's morphological analysis remained more advanced than any equivalent Western theory until the mid-20th century. Metal currency was minted in India before the 5th century BCE, with coinage (400 BCE—100 CE) being made of silver and copper, bearing animal and plant symbols on them.

Zinc mines of Zawar, near Udaipur, Rajasthan, were active during 400 BCE. Diverse specimens of swords have been discovered in Fatehgarh, where there are several varieties of hilt. These swords have been variously dated to periods between 1700–1400 BCE, but were probably used more extensively during the opening centuries of the 1st millennium BCE. Archaeological sites in such as Malhar, Dadupur, Raja Nala Ka Tila and Lahuradewa in present-day Uttar Pradesh show iron implements from the period between 1800 BCE and 1200 BCE. Early iron objects found in India can be dated to 1400 BCE by employing the method of radio carbon dating. Some scholars believe that by the early 13th century BCE iron smelting was practiced on a bigger scale in India, suggesting that the date of the technology's inception may be placed earlier. In Southern India (present day Mysore) iron appeared as early as 11th to 12th centuries BCE. These developments were too early for any significant close contact with the northwest of the country.

Post Maha Janapadas—High Middle Ages

The iron pillar of Delhi (375–413 CE). The first iron pillar was the Iron pillar of Delhi, erected at the times of Chandragupta II Vikramaditya.

The Arthashastra of Kautilya mentions the construction of dams and bridges. The use of suspension bridges using plaited bamboo and iron chain was visible by about the 4th century. The stupa, the precursor of the pagoda and torii, was constructed by the 3rd century BCE. Rock-cut step wells in the region date from 200-400 CE. Subsequently, the construction of wells at Dhank (550-625 CE) and stepped ponds at Bhinmal (850-950 CE) took place.

During the 1st millennium BCE, the Vaisheshika school of atomism was founded. The most important proponent of this school was Kanada, an Indian philosopher who lived around 600 BCE. The school proposed that atoms are indivisible and eternal, can neither be created nor destroyed, and that each one possesses its own distinct viśeṣa (individuality). It was further elaborated on by the Buddhist school of atomism, of which the philosophers Dharmakirti and Dignāga in the 7th century CE were the most important proponents. They considered atoms to be point-sized, durationless, and made of energy.

By the beginning of the Common Era glass was being used for ornaments and casing in the region. Contact with the Greco-Roman world added newer techniques, and local artisans learnt methods of glass molding, decorating and coloring by the early centuries of the Common Era. The Satavahana period further reveals short cylinders of composite glass, including those displaying a lemon yellow matrix covered with green glass. Wootz originated in the region before the beginning of the common era. Wootz was exported and traded throughout Europe, China, the Arab world, and became particularly famous in the Middle East, where it became known as Damascus steel. Archaeological evidence suggests that manufacturing process for Wootz was also in existence in South India before the Christian era.

Evidence for using bow-instruments for carding comes from India (2nd century CE). The mining of diamonds and its early use as gemstones originated in India. Golconda served as an important early center for diamond mining and processing. Diamonds were then exported to other parts of the world. Early reference to diamonds comes from Sanskrit texts. The Arthashastra also mentions diamond trade in the region. The Iron pillar of Delhi was erected at the times of Chandragupta II Vikramaditya (375–413), which stood without rusting for around 2 millennium. The Rasaratna Samuccaya (800) explains the existence of two types of ores for zinc metal, one of which is ideal for metal extraction while the other is used for medicinal purpose.

Model of a Chola (200–848) ship's hull, built by the ASI, based on a wreck 19 miles off the coast of Poombuhar, displayed in a Museum in Tirunelveli.

The origins of the spinning wheel are unclear but India is one of the probable places of its origin. The device certainly reached Europe from India by the 14th century. The cotton gin was invented in India as a mechanical device known as charkhi, the "wooden-worm-worked roller". This mechanical device was, in some parts of the region, driven by water power. The Ajanta caves yield evidence of a single roller cotton gin in use by the 5th century. This cotton gin was used until further innovations were made in form of foot powered gins. Chinese documents confirm at least two missions to India, initiated in 647, for obtaining technology for sugar-refining. Each mission returned with different results on refining sugar. Pingala (300-200 BCE) was a musical theorist who authored a Sanskrit treatise on prosody. There is evidence that in his work on the enumeration of syllabic combinations, Pingala stumbled upon both the Pascal triangle and Binomial coefficients, although he did not have knowledge of the Binomial theorem itself. A description of binary numbers is also found in the works of Pingala. The Indians also developed the use of the law of signs in multiplication. Negative numbers and the subtrahend had been used in East Asia since the 2nd century BCE, and Indian mathematicians were aware of negative numbers by the 7th century CE, and their role in mathematical problems of debt was understood. Although the Indians were not the first to use the subtrahend, they were the first to establish the "law of signs" with regards to the multiplication of positive and negative numbers, which did not appear in East Asian texts until 1299. Mostly consistent and correct rules for working with negative numbers were formulated, and the diffusion of these rules led the Arab intermediaries to pass it on to Europe.

A decimal number system using hieroglyphics dates back to 3000 BC in Egypt, and was later in use in ancient India where the modern numeration system was developed. By the 9th century CE, the Hindu–Arabic numeral system was transmitted from India through the Middle East and to the rest of the world. The concept of 0 as a number, and not merely a symbol for separation is attributed to India. In India, practical calculations were carried out using zero, which was treated like any other number by the 9th century CE, even in case of division. Brahmagupta (598–668) was able to find (integral) solutions of Pell's equation. Conceptual design for a perpetual motion machine by Bhaskara II dates to 1150. He described a wheel that he claimed would run forever.

The trigonometric functions of sine and versine, from which it was trivial to derive the cosine, were used by the mathematician, Aryabhata, in the late 5th century. The calculus theorem now known as "Rolle's theorem" was stated by mathematician, Bhāskara II, in the 12th century.

Akbarnama—written by August 12, 1602—depicts the defeat of Baz Bahadur of Malwa by the Mughal troops, 1561. The Mughals extensively improved metal weapons and armor used by the armies of India.

Indigo was used as a dye in India, which was also a major center for its production and processing. The Indigofera tinctoria variety of Indigo was domesticated in India. Indigo, used as a dye, made its way to the Greeks and the Romans via various trade routes, and was valued as a luxury product. The cashmere wool fiber, also known as pashm or pashmina, was used in the handmade shawls of Kashmir. The woolen shawls from Kashmir region find written mention between 3rd century BCE and the 11th century CE. Crystallized sugar was discovered by the time of the Gupta dynasty, and the earliest reference to candied sugar comes from India. Jute was also cultivated in India. Muslin was named after the city where Europeans first encountered it, Mosul, in what is now Iraq, but the fabric actually originated from Dhaka in what is now Bangladesh. In the 9th century, an Arab merchant named Sulaiman makes note of the material's origin in Bengal (known as Ruhml in Arabic).

European scholar Francesco I reproduced a number of Indian maps in his magnum opus La Cartografia Antica dell India. Out of these maps, two have been reproduced using a manuscript of Lokaprakasa, originally compiled by the polymath Ksemendra (Kashmir, 11th century CE), as a source. The other manuscript, used as a source by Francesco I, is titled Samgraha'.
 
Samarangana Sutradhara, a Sanskrit treatise by Bhoja (11th century), includes a chapter about the construction of mechanical contrivances (automata), including mechanical bees and birds, fountains shaped like humans and animals, and male and female dolls that refilled oil lamps, danced, played instruments, and re-enacted scenes from Hindu mythology.

Late Middle Ages

Jantar Mantar, Delhi—consisting of 13 architectural astronomy instruments, built by Jai Singh II of Jaipur, from 1724 onwards.

Madhava of Sangamagrama (c. 1340 – 1425) and his Kerala school of astronomy and mathematics developed and founded mathematical analysis. The infinite series for π was stated by him, and he made use of the series expansion of \arctan x to obtain an infinite series expression, now known as the Madhava-Gregory series, for \pi . Their rational approximation of the error for the finite sum of their series are of particular interest. They manipulated the error term to derive a faster converging series for \pi . They used the improved series to derive a rational expression, 104348/33215 for \pi correct up to nine decimal places, i.e. 3.141592653 (of 3.1415926535897...). The development of the series expansions for trigonometric functions (sine, cosine, and arc tangent) was carried out by mathematicians of the Kerala School in the 15th century CE. Their work, completed two centuries before the invention of calculus in Europe, provided what is now considered the first example of a power series (apart from geometric series).

Shēr Shāh of northern India issued silver currency bearing Islamic motifs, later imitated by the Mughal empire. The Chinese merchant Ma Huan (1413–51) noted that gold coins, known as fanam, were issued in Cochin and weighed a total of one fen and one li according to the Chinese standards. They were of fine quality and could be exchanged in China for 15 silver coins of four-li weight each.

In 1500, Nilakantha Somayaji of the Kerala school of astronomy and mathematics, in his Tantrasangraha, revised Aryabhata's elliptical model for the planets Mercury and Venus. His equation of the centre for these planets remained the most accurate until the time of Johannes Kepler in the 17th century.

The seamless celestial globe was invented in Kashmir by Ali Kashmiri ibn Luqman in 998 AH (1589-90 CE), and twenty other such globes were later produced in Lahore and Kashmir during the Mughal Empire. Before they were rediscovered in the 1980s, it was believed by modern metallurgists to be technically impossible to produce metal globes without any seams, even with modern technology. These Mughal metallurgists pioneered the method of lost-wax casting in order to produce these globes.

Portrait of a young Indian scholar, Mughal miniature by Mir Sayyid Ali, c. 1550.

Gunpowder and gunpowder weapons were transmitted to India through the Mongol invasions of India. The Mongols were defeated by Alauddin Khalji of the Delhi Sultanate, and some of the Mongol soldiers remained in northern India after their conversion to Islam. It was written in the Tarikh-i Firishta (1606–1607) that the envoy of the Mongol ruler Hulagu Khan was presented with a pyrotechnics display upon his arrival in Delhi in 1258 CE. As a part of an embassy to India by Timurid leader Shah Rukh (1405–1447), 'Abd al-Razzaq mentioned naphtha-throwers mounted on elephants and a variety of pyrotechnics put on display. Firearms known as top-o-tufak also existed in the Vijayanagara Empire by as early as 1366 CE. From then on the employment of gunpowder warfare in the region was prevalent, with events such as the siege of Belgaum in 1473 CE by the Sultan Muhammad Shah Bahmani.

In A History of Greek Fire and Gunpowder, James Riddick Partington describes the gunpowder warfare of 16th and 17th century Mughal India, and writes that "Indian war rockets were formidable weapons before such rockets were used in Europe. They had bamboo rods, a rocket-body lashed to the rod, and iron points. They were directed at the target and fired by lighting the fuse, but the trajectory was rather erratic... The use of mines and counter-mines with explosive charges of gunpowder is mentioned for the times of Akbar and Jahāngir."

By the 16th century, Indians were manufacturing a diverse variety of firearms; large guns in particular, became visible in Tanjore, Dacca, Bijapur and Murshidabad. Guns made of bronze were recovered from Calicut (1504) and Diu (1533). Gujarāt supplied Europe saltpeter for use in gunpowder warfare during the 17th century. Bengal and Mālwa participated in saltpeter production. The Dutch, French, Portuguese, and English used Chhapra as a center of saltpeter refining.

The construction of water works and aspects of water technology in India is described in Arabic and Persian works. During medieval times, the diffusion of Indian and Persian irrigation technologies gave rise to an advanced irrigation system which bought about economic growth and also helped in the growth of material culture. The founder of the cashmere wool industry is traditionally held to be the 15th-century ruler of Kashmir, Zayn-ul-Abidin, who introduced weavers from Central Asia.

The scholar Sadiq Isfahani of Jaunpur compiled an atlas of the parts of the world which he held to be 'suitable for human life'. The 32 sheet atlas—with maps oriented towards the south as was the case with Islamic works of the era—is part of a larger scholarly work compiled by Isfahani during 1647 CE. According to Joseph E. Schwartzberg (2008): 'The largest known Indian map, depicting the former Rajput capital at Amber in remarkable house-by-house detail, measures 661 × 645 cm. (260 × 254 in., or approximately 22 × 21 ft).'

Colonial era

Early volumes of the Encyclopædia Britannica described cartographic charts made by the seafaring Dravidian people. In Encyclopædia Britannica (2008), Stephen Oliver Fought & John F. Guilmartin, Jr. describe the gunpowder technology in 18th-century Mysore:

Hyder Ali, prince of Mysore, developed war rockets with an important change: the use of metal cylinders to contain the combustion powder. Although the hammered soft iron he used was crude, the bursting strength of the container of black powder was much higher than the earlier paper construction. Thus a greater internal pressure was possible, with a resultant greater thrust of the propulsive jet. The rocket body was lashed with leather thongs to a long bamboo stick. Range was perhaps up to three-quarters of a mile (more than a kilometre). Although individually these rockets were not accurate, dispersion error became less important when large numbers were fired rapidly in mass attacks. They were particularly effective against cavalry and were hurled into the air, after lighting, or skimmed along the hard dry ground. Hyder Ali's son, Tippu Sultan, continued to develop and expand the use of rocket weapons, reportedly increasing the number of rocket troops from 1,200 to a corps of 5,000. In battles at Seringapatam in 1792 and 1799 these rockets were used with considerable effect against the British.

By the end of the 18th century the postal system in the region had reached high levels of efficiency. According to Thomas Broughton, the Maharaja of Jodhpur sent daily offerings of fresh flowers from his capital to Nathadvara (320 km) and they arrived in time for the first religious Darshan at sunrise. Later this system underwent modernization with the establishment of the British Raj. The Post Office Act XVII of 1837 enabled the Governor-General of India to convey messages by post within the territories of the East India Company. Mail was available to some officials without charge, which became a controversial privilege as the years passed. The Indian Post Office service was established on October 1, 1837. The British also constructed a vast railway network in the region for both strategic and commercial reasons.

The British education system, aimed at producing able civil and administrative services candidates, exposed a number of Indians to foreign institutions. Sir Jagadis Chandra Bose (1858–1937), Prafulla Chandra Ray (1861-1944), Satyendra Nath Bose (1894–1974), Meghnad Saha (1893–1956), P. C. Mahalanobis (1893–1972), Sir C. V. Raman (1888–1970), Subrahmanyan Chandrasekhar (1910–1995), Homi Bhabha (1909–1966), Srinivasa Ramanujan (1887–1920), Vikram Sarabhai (1919–1971), Har Gobind Khorana (1922–2011), Harish Chandra (1923–1983), and Abdus Salam (1926-1996) were among the notable scholars of this period.

Extensive interaction between colonial and native sciences was seen during most of the colonial era. Western science came to be associated with the requirements of nation building rather than being viewed entirely as a colonial entity, especially as it continued to fuel necessities from agriculture to commerce. Scientists from India also appeared throughout Europe. By the time of India's independence colonial science had assumed importance within the westernized intelligentsia and establishment.

French astronomer, Pierre Janssen observed the Solar eclipse of 18 August 1868 and discovered helium, from Guntur in Madras State, British India.

Lie point symmetry

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