The spark that fired the Great Trigonometrical Survey of India: the triangulation survey made between Fort St. George (13 degrees 08 ' N) and Mangalore (12 degrees 91 ' N) by William Lambton in the early 1800s

摘要

In 1800, the English East-India Company at Fort St. George (approximate to Madras) ordered surveys of peninsular India for political reasons. William Lambton of the 33rd Regiment of Foot - who had just arrived in Madras to join the army marching against the Mysore Tiger Tipu Sultan in 1799 - started the scientifically accurate landscape measurement using trigonometric methods in 1801, one of the three major surveys that were concurrently launched and referred in the pages of India's science history as the Great Trigonometrical Survey of India (GTSI). Lambton led this project until his death in Hinganghat ( presently in Maharashtra) in 1823. From then, his trainee George Everest took over and completed the project. Much has been written about the Lambton-Everest GTSI, but little has been mentioned on the preliminary survey that Lambton carried out from 1804 of the landscape between Fort St. George (Madras), Bangalore and Mangalore, and on fixing the global coordinates of the towns in between. The science used in this survey of c. 360 miles (570 km) between the Coromandel and the Malabar Coasts is stunning in terms of its accuracy of details, given the quality of tools and gadgets Lambton and his team used. This survey was the spark that fired GTSI. The Fort St. George-Bangalore-Mangalore survey on completion in 1810, progressed slightly northwards and southwards initially and later got extended all over British India. The Madras Observatory established by Michael Topping and the pioneering astronomy and physics - built on elegant mathematics - marshalled by his successor John Goldingham offered considerable scientific back-up and clarity to Lambton's GTSI project.