Lee ihe e dere n'okpuru ebe a ma zaa ajụjụ ahụ n'otu asụsụ ahụ dị n'okpuru ebe a: Ihe e dere n'okpuru ebe a: The Great Trigonometrical Survey bụ oru ngo nke ebumnuche ya bụ iji tụọ ihe niile dị n'akụkụ ụwa India na nkenke sayensị. Ọ malitere na 1802 site n'aka onye ọrụ ndị agha William Lambton, n'okpuru nkwado nke East India Company. N'okpuru nduzi nke onye nọchiri ya, George Everest, e mere ọrụ ahụ ka ọ bụrụ ọrụ nke Nyocha nke India. Everest bụ Andrew Scott Waugh nọchiri ya na mgbe 1861 gasịrị, James Walker duziri ọrụ ahụ, bụ onye hụrụ ka emechara ya na 1871. Ajụjụ: Gịnị bụ ebumnuche nke Great Trigonometrical Survey?
na-atụle ihe nile dị n'India