1. IOR/V/27/420/104 Reference (shelfmark): IOR/V/27/420/104 Title: Pogson, Norman R., Telegraphic determinations of the difference of longitude between Karachi, Avanashi, Roorkee, Pondicherry, Colombo, Jaffna, Muddapur and Singapore, and the Government Observatory, Madras. Madras: Lawrence Asylum Press, 1884 Collection Area: India Office Records and Private Papers Languages: English Date Range: 1884 Extent: 1 volume