1. IOR/V/27/420/84 Reference (shelfmark): IOR/V/27/420/84 Title: India. Survey of India, Trigonometrical Branch Spirit-Levelled heights: Bengal Presidency 1881-88. Dehra Dun, 1863-1903 Collection Area: India Office Records and Private Papers Languages: English Date Range: 1863-1903 Extent: 1 volume