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48-631: The Great Trigonometrical Survey of India was a project that aimed to carry out a survey across the Indian subcontinent with scientific precision. It was begun in 1802 by the British infantry officer William Lambton , under the auspices of the East India Company . Under the leadership of his successor, George Everest , the project was made the responsibility of the Survey of India . Everest

96-509: A rod (or pole ). Ten chains measure a furlong and 80 chains measure a statute mile . Gunter's chain reconciled two seemingly incompatible systems: the traditional English land measurements, based on the number four, and decimals based on the number 10. Since an acre measured 10 square chains in Gunter's system, the entire process of land area measurement could be computed using measurements in chains, and then converted to acres by dividing

144-501: A "gridiron" of triangulation chains running from north to south and east to west. At times the survey party numbered 700 people. The Trigonometrical Survey was conducted independently of other surveys, notably the topographical and revenue surveys. In 1875, the decision was taken that the Survey budget should be reduced from 240,000 to 200,000 pounds. This resulted in a reorganization under Surveyor-General Colonel J.T. Walker to amalgamate

192-658: A 200-link chain of two rods (33 feet, 10.0584 m) length. Each rod (or perch or pole) consists of 100 links, (1.98 inches, 50.292 mm each), which are called seconds (″), ten of which make a prime ( ′ , 19.8 inches, 0.503 m). Vincent Wing made chains with 9.90-inch links, most commonly as 33-foot half-chains of 40 links. These chains were sometimes used in the American colonies, particularly Pennsylvania. In India , surveying chains 20 metres (65 ft 7.4 in) (occasionally 30 metres) in length are used. Links are 200 millimetres (7.87 in) long. In France after

240-451: A baseline near Madras . Major Lambton selected the flat plains with St. Thomas Mount at the north end and Perumbauk hill at the southern end. The baseline was 7.5 miles (12.1 km) long. Lieutenant Kater was despatched to find high vantage points on the hills of the west so that the coastal points of Tellicherry and Cannanore could be connected. The high hills chosen were Mount Delly and Tadiandamol . The distance from coast to coast

288-435: A chainman. A ranging rod (usually a prominently coloured wooden pole) is placed in the ground at the destination point. Starting at the originating point the chain is laid out towards the ranging rod, and the surveyor then directs the chainman to make the chain perfectly straight and pointing directly at the ranging rod. A pin is put in the ground at the forward end of the chain, and the chain is moved forward so that its hind end

336-424: A cricket context, these countries are often referred to simply as the subcontinent around the world e.g. " Australia's tour of the subcontinent". The word is also sometimes used as an adjective in this context e.g. "subcontinental conditions". The Indian subcontinent was formerly part of Gondwana , a supercontinent formed during the late Neoproterozoic and early Paleozoic . Gondwana began to break up during

384-593: A distinct political entity that eventually became a nation-state (today the Republic of India). According to the Oxford English Dictionary , the term subcontinent signifies a "subdivision of a continent which has a distinct geographical, political, or cultural identity" and also a "large land mass somewhat smaller than a continent". Its use to signify the Indian subcontinent is evidenced from

432-476: A handle which may or may not be part of the measurement. An inner loop (visible in the NMAH photograph) is the correct place to put the pin for some chains. Many chains were made with the handles as part of the end link and thus were included in the measurement. The whole process is repeated for all the other pairs of points required, and it is a simple matter to make a scale diagram of the plot of land. The process

480-645: A region or a 'realm' by itself than the Indian subcontinent." This natural physical landmass in South Asia is the dry-land portion of the Indian Plate , which has been relatively isolated from the rest of Eurasia. The Himalayas (from Brahmaputra River in the east to Indus River in the west), Karakoram (from Indus River in the east to Yarkand River in the west) and the Hindu Kush mountains (from Yarkand River westwards) form its northern boundary. In

528-482: A small archipelago southwest of the peninsula, while largely considered a part of the Indian subcontinent, sometimes is mentioned by sources, including the International Monetary Fund , as a group of islands away from the Indian subcontinent in a south-western direction. The population of Indian subcontinent is about 1.912 billion which makes it the most populated region in the world. It

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576-534: A term closely linked to the region's colonial heritage, as a cover term, the latter is still widely used in typological studies. Since the Partition of India , citizens of Pakistan (which became independent of British India in 1947) and Bangladesh (which became independent of Pakistan in 1971) often perceive the use of the Indian subcontinent as offensive and suspicious because of the dominant placement of India in

624-552: Is Ramsden's or the engineer's system , where the chain consists also of 100 links, each one foot (0.3048 m) long. The original of such chains was that constructed, to very high precision, for the measurement of the baselines of the Anglo-French Survey (1784–1790) and the Principal Triangulation of Great Britain . The even less common Rathborn system , also from the 17th century, is based on

672-822: Is a peninsular region in South Asia delineated by the Himalayas in the north, the Hindu Kush in the west, and the Arakanese in the east. It extends southward into the Indian Ocean with the Arabian Sea to the southwest and the Bay of Bengal to the southeast. Most of this region rests on the Indian Plate and is isolated from the rest of Asia by large mountain barriers. Laccadive Islands , Maldives and

720-588: Is a physiographical region in Southern Asia , mostly situated on the Indian Plate , projecting southwards into the Indian Ocean from the Himalayas . Geographically, it spans the countries of Bangladesh , Bhutan , the British Indian Ocean Territory (United Kingdom), India , Maldives , Nepal , Pakistan , and Sri Lanka . Although the terms "Indian subcontinent" and "South Asia" are often used interchangeably to denote

768-452: Is at that point, and the chain is extended again towards the destination point. This process is called ranging , or in the US, chaining; it is repeated until the destination rod is reached, when the surveyor notes how many full lengths (chains) have been laid, and he can then directly read how many links (one-hundredth parts of the chain) are in the distance being measured. The chain usually ends in

816-736: Is socially very mixed, consisting of many language groups and religions, and social practices in one region that are vastly different from those in another. [REDACTED] Media related to Indian subcontinent at Wikimedia Commons [REDACTED] Africa [REDACTED] Antarctica [REDACTED] Asia [REDACTED] Australia [REDACTED] Europe [REDACTED] North America [REDACTED] South America [REDACTED] Afro-Eurasia [REDACTED] Americas [REDACTED] Eurasia [REDACTED] Oceania Folding chain Gunter developed an actual measuring chain of 100 links. These,

864-428: Is somewhat contested as there is no globally accepted definition on which countries are a part of South Asia or the Indian subcontinent. Whether called the Indian subcontinent or South Asia, the definition of the geographical extent of this region varies. Afghanistan , despite often considered as a part of South Asia, is usually not included in the Indian subcontinent. Maldives, an island country consisting of

912-399: Is surprisingly accurate and requires only very low technology. Surveying with a chain is simple if the land is level and continuous—it is not physically practicable to range across large depressions or significant waterways, for example. On sloping land, the chain was to be "leveled" by raising one end as needed, so that undulations did not increase the apparent length of the side or the area of

960-650: The 26 atolls of the Maldives lie entirely within the Southern Hemisphere. Historically, the region surrounding and southeast of the Indus River was often simply referred to as "India" in many historical sources. Even today, historians use this term to denote the entire Indian subcontinent when discussing history up until the era of the British Raj. Over time, however, "India" evolved to refer to

1008-660: The Chagos Archipelago are three series of coral atolls , cays and Faroes on the Indian Plate along with the Chagos–Laccadive Ridge , a submarine ridge that was generated by the northern drift of the Indian Plate over the Réunion hotspot during the Cretaceous and early Cenozoic times. The Maldives archipelago rises from a basement of volcanic basalt outpourings from a depth of about 2000 m forming

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1056-768: The Mesozoic , with Insular India separating from Antarctica 130-120 million years ago and Madagascar around 90 million years ago, during the Cretaceous . Insular India subsequently drifted northeastwards, colliding with the Eurasian Plate nearly 55 million years ago, during the Eocene , forming the Indian subcontinent. The zone where the Eurasian and Indian subcontinent plates meet remains geologically active, prone to major earthquakes. Physiographically , it

1104-535: The chain and the link , became statutory measures in England and subsequently the British Empire . The 66-foot (20.1 m) chain is divided into 100 links, usually marked off into groups of 10 by brass rings or tags which simplify intermediate measurement. Each link is thus 7.92 inches (201 mm) long. A quarter chain, or 25 links, measures 16 feet 6 inches (5.03 m) and thus measures

1152-470: The Englishs Mile and Acre, 10 such Chains in length making a Furlong, and 10 single square Chains an Acre, so that a square Mile contains 640 square Acres...' The method of surveying a field or other parcel of land with Gunter's chain is to first determine corners and other significant locations, and then to measure the distance between them, taking two points at a time. The surveyor is assisted by

1200-480: The Great Trigonometrical, Topographical and Revenue Surveys into the Survey of India. Triangulation surveys were based on a few carefully measured baselines and a series of angles. The initial baseline was measured with great care since the accuracy of the subsequent survey was critically dependent upon it. Various corrections were applied, principally temperature. An especially accurate folding chain

1248-468: The Indian coast through the maritime routes on the Arabian Sea. In terms of modern geopolitical boundaries, the subcontinent constitutes Bangladesh , Bhutan , India, Nepal , and Pakistan , besides, by convention, the island country of Sri Lanka and other nearby island nations of the Indian Ocean, such as Maldives and the British Indian Ocean Territory . Unlike "South Asia", sometimes

1296-406: The Indian subcontinent has come to be known as South Asia "in more recent and neutral parlance". Indologist Ronald B. Inden argues that the usage of the term South Asia is becoming more widespread since it clearly distinguishes the region from East Asia. While South Asia , a more accurate term that reflects the region's contemporary political demarcations, is replacing the Indian subcontinent ,

1344-482: The central part of the ridge between Laccadives and the Great Chagos Bank . According to anthropologist Patrap C. Dutta, "the Indian subcontinent occupies the major landmass of South Asia." According to historian B. N. Mukherjee , "The subcontinent is an indivisible geographical entity." According to geographer Dudley Stamp , "There is perhaps no mainland part of the world better marked off by nature as

1392-567: The chain unit to maintain the consistency of a two-hundred-year-old database. In the Midwest of the US it is not uncommon to encounter deeds with references to chains, poles, or rod units, especially in farming country. Minor roads surveyed in Australia and New Zealand in the 19th and early 20th centuries are customarily one chain wide. The length of a cricket pitch is one chain (22 yards). A similar American system, of lesser popularity,

1440-478: The construction of instruments. He had a maker, Henry Barrow, set up an instrument company in Calcutta. Barrow was succeeded by Syed Mohsin from Arcot, Tamil Nadu , and after his death, the instruments were supplied by Cooke from York . To achieve the highest accuracy, a number of corrections were applied to all distances calculated from simple trigonometry: Indian subcontinent The Indian subcontinent

1488-568: The early twentieth century when most of the territory was either part of the British Empire or allied with them. It was a convenient term to refer to the region comprising both British India and the princely states . The term has been particularly common in the British Empire and its successors, while the term South Asia is the more common usage in Europe and North America. According to historians Sugata Bose and Ayesha Jalal ,

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1536-481: The east, it is bounded by Patkai , Naga , Lushai and Chin hills. The Indian Ocean, Bay of Bengal and the Arabian Sea form the boundary of the Indian subcontinent in the south, south-east and south-west. Given the difficulty of passage through the Himalayas, the sociocultural, religious and political interaction of the Indian subcontinent has largely been through the valleys of Afghanistan in its northwest,

1584-537: The entire Indian subcontinent by the beginning of the nineteenth century, the British East India Company gained more and more territory. With the acquisition of new territory, it employed several explorers and cartographers to provide maps and other information on its territories, most notably James Rennell , from 1767 in Bengal . As Rennell proceeded to make maps, the lack of precise measurement

1632-444: The expression "Indian subcontinent" may exclude the islands of Maldives and Sri Lanka. According to Pawan Budhwar, Arup Varma, and Manjusha Hirekhan, India, Pakistan, Bangladesh, Sri Lanka, Nepal and Bhutan constitute the Indian subcontinent. Budhwar, Varma, and Hirekhan also maintain that with Afghanistan and Maldives included the region is referred to as South Asia. The periphery of the subcontinent, including Bangladesh, Pakistan, and

1680-417: The island chains of Maldives, features large Muslim populations, while the heartland, including most of India, Nepal, and Sri Lanka, are overwhelmingly Hindu or Buddhist. Since most of these countries are located on the Indian Plate, a continuous landmass , the borders between countries are often either a river or a no man's land . The precise definition of an "Indian subcontinent" in a geopolitical context

1728-628: The landmass of Eurasia nearly 55 million years ago, forming the Himalayas. It is one of the most populated regions in the world, holding roughly 20–25 percent of the global population. Geographically, the peninsular region in Southern Asia is located below the Third Pole , delineated by the Himalayas in the north, the Hindu Kush in the west, and the Indo-Burman Ranges in the east. The neighboring geographical regions around

1776-431: The region, the geopolitical term of South Asia frequently includes Afghanistan , which is not considered a part of the subcontinent, while excluding the British Indian Ocean Territory which is geologically associated with the subcontinent. Geologically, the subcontinent originates from Insular India , an isolated landmass that rifted from the supercontinent of Gondwana during the Cretaceous and merged with

1824-474: The results by 10. Hence 10 chains by 10 chains (100 square chains) equals 10 acres, 5 chains by 5 chains (25 square chains) equals 2.5 acres. By the 1670s the chain and the link had become statutory units of measurement in England. ...a Word or two of Dimensurators or Measuring Instruments, whereof the mosts usual has been the Chain, and the common length for English Measures 4 Poles, as answering indifferently to

1872-766: The subcontinent include the Tibetan Plateau to the north, the Indochinese Peninsula to the east, the Iranian Plateau to the west, and the Indian Ocean to the south. Apart from Maritime Southeast Asia (the Malay Archipelago ), the maritime region of the subcontinent ( littoral South Asia ) is the only subregion of Asia that lies partly within the Southern Hemisphere : the British Indian Ocean Territory two of

1920-534: The term. As such it is being increasingly less used in those countries. Meanwhile, many Indian analysts prefer to use the term because of the socio-cultural commonalities of the region. The region has also been called the "Asian subcontinent", the "South Asian subcontinent", as well as "India" or " Greater India " in the classical and pre-modern sense. The sport of cricket is notably popular in India , Pakistan , Sri Lanka , Nepal and Bangladesh . Within

1968-515: The tract. Although link chains were later superseded by the steel ribbon tape (a form of tape measure ), its legacy was a new statutory unit of length called the chain, equal to 22 yards (66 feet) of 100 links . This unit still exists as a location identifier on British railways, as well as all across America in what is called the public land survey system. In the United States (US), for example, Public Lands Survey plats are published in

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2016-457: The valleys of Manipur in its east, and by maritime routes . More difficult but historically important interaction has also occurred through passages pioneered by the Tibetans . These routes and interactions have led to the spread of Buddhism out of the subcontinent into other parts of Asia. The Islamic expansion arrived into the subcontinent in two ways: through Afghanistan on land, and to

2064-726: The west it is bounded by parts of the mountain ranges of Hindu Kush , Spīn Ghar (Safed Koh), Sulaiman Mountains , Kirthar Mountains , Brahui range, and Pab range among others, with the Western Fold Belt along the border (between the Sulaiman Range and the Chaman Fault) is the western boundary of the Indian Plate, where, along the Eastern Hindu Kush, lies the Afghanistan–Pakistan border. In

2112-519: Was 360 miles (580 km) and this survey line was completed in 1806. The East India Company thought that this project would take about five years, but it took nearly 70 years, well past the Indian Rebellion of 1857 and the end of company rule in India . Because of the extent of the land to be surveyed, the surveyors did not triangulate the whole of India but instead created what they called

2160-472: Was noticed. In 1800, shortly after the Company victory over Tipu Sultan , William Lambton, an infantry soldier with experience in surveying, proposed to remedy precisely that, through a series of triangulations , initially through the newly-acquired territory of Mysore , and eventually across the entire subcontinent . The Great Trigonometrical Survey of India started on 10 April 1802 with the measurement of

2208-573: Was responsible for one of the first accurate measurements of a section of an arc of longitude , and for measurements of the geodesic anomaly , which led to the development of the theories of isostasy . The native surveyors made use of in the Himalayas, especially in Tibet (where Europeans were not allowed), were called pundits , who included the cousins Nain Singh Rawat and Krishna Singh Rawat . From its inception in 1600 to its domination of

2256-458: Was succeeded by Andrew Scott Waugh , and after 1861, the project was led by James Walker , who oversaw its completion in 1871. Among the many accomplishments of the Survey were the demarcation of the British territories in the subcontinent and the measurement of the height of the Himalayan giants: Everest , K2 , and Kangchenjunga . The Survey had an enormous scientific impact as well. It

2304-431: Was used, laid on horizontal tables, all shaded from the sun and with constant tension. The early surveys made use of large and bulky theodolites made by William Carey, a zenith sector made by Jesse Ramsden , and 100-foot (30 m) chains. Later surveys used more compact theodolites. Accurate instruments could not always be purchased through the standard system of government contract, and Everest personally supervised

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