1. IOR/V/19/2 Reference (shelfmark): IOR/V/19/2 Title: Account of the Operations of the Great Trigonometrical Survey of India, Vol 2, History and general description of the principal triangulation and of its reduction. J.T. Walker. Dehra Dun, 1879 Collection Area: India Office Records and Private Papers Languages: English Date Range: 1879 Extent: 1 volume