1. IOR/L/E/6/42, File 548 Reference (shelfmark): IOR/L/E/6/42, File 548 Title: File S&C 548/1880 - Letter of the Surveyor General of India, Major-General J T Walker, dated 15th March 1880, and related correspondence, relating to the utilization of the services of Mr Roberts in connection with the tide calculating machine Collection Area: India Office Records and Private Papers Languages: English Date Range: Mar 1880-Aug 1880 Extent: 1 file