British traders became a territorial power in Bengal in 1757. Within 60 years they had the whole of India under their control. The British in India had their tasks clearly laid out from the very beginning. Administration had to be set up in the acquired territories; new lands had to be conquered; and land revenue ( and trade profits) enhanced. Military geography went hand in hand with the administrative.
(i) Whatever geographical information was available in pre-existing scientific and political documents was taken out and utilized. (ii) Local people were hired as messengers to bring in intelligence on routes, roads, rivers, bridges, hills, etc.
(iii) Jesuits and ex-Jesuits took modern measurements and obtained valuable primary data.
(iv) Whenever an opportunity presented itself, Company officials made surveys.
(v) Lastly, as soon as it became possible, an exhaustive systematic field survey was ordered.
The geographic and geodesic work done in India under European auspices during the 17th and 18th centuries got eclipsed by the spectacular 19th century developments (epitomised by the naming of the highest point on the earth after a surveyor-general), it was solid and extremely significant in its time.