299:
33:
142:
190:
202:
262:
257:
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
278:
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
310:
Accurate instruments could not always be purchased through the standard system of government contract, and
Everest personally supervised the construction of instruments. He had a maker, Henry Barrow, set up an instrument company in Calcutta. Barrow was succeeded by Syed Mohsin from
242:. The distance from coast to coast 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
225:
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
197:. This shows surveyors stretching a chain on coffers supported on pickets. The chain is housed under shade to reduce errors due to thermal expansion, and is aligned using a boning telescope.
162:
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
254:
the whole of India but instead created what they called a "gridiron" of triangulation chains running from north to south and east to west. At times the survey party numbered 700 people.
487:
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84:
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was used, laid on horizontal tables, all shaded from the sun and with constant tension. The early surveys made use of large and bulky
842:
170:. As Rennell proceeded to make maps, the lack of precise measurement was noticed. In 1800, shortly after the Company victory over
541:"An account of the Trigonometrical Operations in crossing the peninsula of India, and connecting Fort St. George with Mangalore"
209:
was an upward-facing telescope with accurate angle measurement scales. A star close to the zenith of known declination from the
941:
385:
77:
32:
327:
To achieve the highest accuracy, a number of corrections were applied to all distances calculated from simple trigonometry:
174:, William Lambton, an infantry soldier with experience in surveying, proposed to remedy precisely that, through a series of
529:
Account of the Pundit's
Journey in Great Tibet - Capt. H. Trotter, The Journal of the Royal Geographical Society (1877).
956:
545:
Asiatic
Researches; or Transactions of the Society Instituted in Bengal for Inquiring into the History and Antiquities
354:
765:"On the Attraction of the Himalaya Mountains, and of the Elevated Regions beyond Them, upon the Plumb-Line in India"
159:
946:
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397:
243:
627:
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The Great
Trigonometrical Survey of India started on 10 April 1802 with the measurement of a baseline near
415:
349:
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was used to determine latitude, as a direct measurement of the pole star could be affected by refraction.
103:. The Survey had an enormous scientific impact as well. It was responsible for one of the first accurate
886:
746:
409:
403:
247:
708:
540:
45:
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to amalgamate the Great
Trigonometrical, Topographical and Revenue Surveys into the Survey of India.
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517:
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Peter
Hopkirk, 1982, "Trespassers on the Roof of the World: The Race for Lhasa",
295:, and 100-foot (30 m) chains. Later surveys used more compact theodolites.
339:
261:
239:
171:
852:
Mapping The Great Game: Explorers, Spies & Maps in
Nineteenth-century Asia
284:
227:
828:
811:
Mapping an Empire: The
Geographical Construction of British India, 1765-1843
732:"Making mountains out of molehills? George Everest and Henry Barry, 1830–39"
210:
108:
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was a small, low-magnification telescope used to align the survey markers.
250:. Because of the extent of the land to be surveyed, the surveyors did not
343:
116:
88:
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territories in the subcontinent and the measurement of the height of the
83:
Among the many accomplishments of the Survey were the demarcation of the
872:"The Great Trigonometrical Survey of India in a Historical Perspective"
303:
218:
790:
231:
764:
315:, and after his death, the instruments were supplied by Cooke from
670:. London: Secretary of State for India in Council. pp. 39–40.
479:
Gill, B. (2001); "THE BIG MAN. Surveying Sir George Everest", in:
297:
260:
200:
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Measurement of the Calcutta baseline in 1832 based on a sketch by
188:
140:
123:
31:
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The native surveyors made use of in the Himalayas, especially in
316:
625:, 29 January 2011,"History: The Great Trigonometrical Survey"
154:
From its inception in 1600 to its domination of the entire
96:
628:"BlueSci » History: The Great Trigonometrical Survey"
518:
The Pundits: British Exploration of Tibet and Central Asia
769:
Philosophical Transactions of the Royal Society of London
52:
with scientific precision. It was begun in 1802 by the
336:
The non-spherical nature of the curvature of the Earth
27:
19th-century survey to measure the Indian subcontinent
178:, initially through the newly-acquired territory of
713:
Professional Papers of the Corps of Royal Engineers
558:
115:, which led to the development of the theories of
68:, the project was made the responsibility of the
648:: CS1 maint: bot: original URL status unknown (
601:(2 ed.). London. W H Allen And Co. p.
158:by the beginning of the nineteenth century, the
126:(where Europeans were not allowed), were called
900:5 vols. Dehra Dun, Survey of India (1945–1968)
234:could be connected. The high hills chosen were
623:Bluesci: Cambridge university science magazine
221:. Major Lambton selected the flat plains with
145:The first triangulations across the Peninsula
8:
630:. Archived from the original on 27 July 2014
898:Historical Records of the Survey of India,
855:. Oxford: Casemate (UK). pp. 67–123.
780:
667:A memoir of the Indian Surveys, 1875–1890
76:, and after 1861, the project was led by
64:. Under the leadership of his successor,
36:Index to the Great Trigonometrical Survey
428:Principal Triangulation of Great Britain
44:was a project that aimed to carry out a
463:
439:
641:
475:
473:
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469:
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80:, who oversaw its completion in 1871.
42:Great Trigonometrical Survey of India
7:
937:1802 establishments in British India
879:Indian Journal of History of Science
739:Indian Journal of History of Science
579:participating institution membership
416:Sir Gerald Ponsonby Lenox-Conyngham
182:, and eventually across the entire
25:
681:R., Ramachandran (2 June 2021) .
520:," University Press of Kentucky.
814:. University of Chicago Press.
962:1871 disestablishments in Asia
598:A Memoir on the Indian Surveys
481:Professional Surveyor Magazine
111:, and for measurements of the
1:
967:19th century in British India
952:Historical geography of India
664:Black, Charles E.D. (1891).
302:One of the survey towers in
274:Instruments and methods used
60:, under the auspices of the
896:Reginald Henry Phillimore,
837:, London: Harper Collins.
355:Height above mean sea level
130:, who included the cousins
72:. Everest was succeeded by
983:
885:(1): 22–32, archived from
808:Edney, Matthew H. (2009).
763:Pratt, John Henry (1855).
745:(1): 47–55. Archived from
483:, Vol. 21 Nr 2. Retrieved
342:influence of mountains on
269:to elevate the instruments
160:British East India Company
107:of a section of an arc of
18:Great Trigonometric Survey
566:Oxford English Dictionary
539:Lambton, William (1811).
287:made by William Carey, a
516:Derek J. Waller, 2004, "
490:10 February 2017 at the
244:Indian Rebellion of 1857
571:Oxford University Press
942:Cartography by country
920:Volume 5: 1844 to 1861
916:Volume 4: 1830 to 1843
912:Volume 3: 1815 to 1830
908:Volume 2: 1800 to 1815
904:Volume 1: 18th Century
870:Deb Roy, Rama (1986),
782:10.1098/rstl.1855.0002
687:frontline.thehindu.com
332:Curvature of the Earth
307:
270:
265:Survey towers used by
214:
198:
146:
37:
730:Insley, Jane (1995).
709:"The Survey of India"
410:Sidney Gerald Burrard
404:St George Corbet Gore
323:Correcting deviations
301:
264:
248:company rule in India
204:
192:
144:
35:
707:Strahan, C. (1903).
849:Dean, Riaz (2019).
752:on 25 January 2014.
569:(Online ed.).
392:Charles Thomas Haig
386:James Thomas Walker
156:Indian subcontinent
136:Krishna Singh Rawat
50:Indian subcontinent
957:Surveying of India
892:on 25 January 2014
380:Andrew Scott Waugh
374:Sir George Everest
308:
271:
215:
199:
147:
74:Andrew Scott Waugh
62:East India Company
38:
862:978-1-61200-814-1
821:978-0-226-18486-9
593:Markham, Clements
577:(Subscription or
505:Oxford University
313:Arcot, Tamil Nadu
16:(Redirected from
974:
947:Geodetic surveys
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448:boning telescope
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223:St. Thomas Mount
132:Nain Singh Rawat
113:geodesic anomaly
54:British infantry
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802:Further reading
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492:Wayback Machine
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368:William Lambton
363:
361:Superintendents
346:and plumb lines
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246:and the end of
166:, from 1767 in
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70:Survey of India
58:William Lambton
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176:triangulations
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66:George Everest
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843:0-00-257062-9
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834:The Great Arc
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683:"Survey Saga"
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494:8 March 2016.
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293:Jesse Ramsden
290:
289:zenith sector
286:
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281:folding chain
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207:zenith sector
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195:James Prinsep
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164:James Rennell
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887:the original
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747:the original
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690:. Retrieved
686:
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659:
654:, Cambridge.
632:. Retrieved
622:
618:
606:. Retrieved
597:
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525:
512:
499:
480:
447:
442:
414:1912–1921 –
408:1899–1911 –
402:1894–1899 –
396:1888–1894 –
390:1884–1888 –
384:1861–1883 –
378:1843–1861 –
372:1823–1843 –
366:1818–1823 –
326:
309:
277:
256:
216:
184:subcontinent
153:
121:
105:measurements
82:
78:James Walker
48:across the
41:
39:
29:
692:26 December
560:"bone, v.3"
285:theodolites
252:triangulate
240:Tadiandamol
236:Mount Delly
228:Tellicherry
172:Tipu Sultan
931:Categories
775:: 53–100.
719:: 141–171.
581:required.)
547:: 290–384.
458:References
350:Refraction
829:John Keay
344:pendulums
279:accurate
232:Cannanore
211:Pole star
109:longitude
89:Himalayan
831:. 2000.
644:cite web
595:(1878).
488:Archived
422:See also
291:made by
117:isostasy
91:giants:
56:officer
608:1 March
306:in 2012
304:Kolkata
150:History
128:pundits
93:Everest
85:British
859:
841:
818:
791:108510
789:
507:Press.
485:online
219:Madras
180:Mysore
168:Bengal
99:, and
46:survey
890:(PDF)
875:(PDF)
787:JSTOR
750:(PDF)
735:(PDF)
634:5 May
575:
434:Notes
124:Tibet
857:ISBN
839:ISBN
816:ISBN
694:2022
650:link
636:2013
610:2009
317:York
238:and
230:and
134:and
40:The
777:doi
773:145
933::
918:;
914:;
910:;
906:;
883:21
881:,
877:,
785:.
771:.
767:.
743:30
741:.
737:.
717:28
715:.
711:.
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642:{{
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824:.
793:.
779::
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652:)
638:.
612:.
573:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
