Muchiitiko che1842, mapoka ekuongorora akafamba achienda kuchamhembe vachishandisa theodolites hombe, imwe neimwe ichirema makirogiramu mazana mashanu uye vachida varume gumi nevaviri kuti vatakure, kuyera kukwirira nenzira chaiyo. Vakasvika kumawere eHimalaya kuma1830s, asi Nepal yakanga isingadi kubvumira maBritish kupinda munyika nekuda kwekusava nechokwadi kwezvematongerwo enyika uye kukwanisa kubatana. Zvikumbiro zvakati wandei nevanoongorora kuti vapinde muNepal zvakarambwa. VaBritish vakamanikidzwa kuenderera mberi nekucherechedza kwavo kubva kuTerai, dunhu rekumaodzanyemba kweNepal riri kuHimalaya. Mamiriro ezvinhu muTalayas akaonekwa nekuda kwemvura inonaya uye marariya.
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