Magnetic observations made at Colaba Observatory, Bombay [Mumbai], India, by [Arthur Bedford Orlebar?] Daily readings of magnetometers at hourly intervals made at the Colaba Observatory. On amended printed sheets, with columns for: 'S.D. in arc', [small declination magnetometer], 'Small H.F.' [horizontal force magnetometer], attached thermometer readings, and Gottingen mean time, for the period until 13 October. From 14 October, additional readings appear, including 'L.D. in arc' [large declination magneometer?], 'Inclinometer in arc', and corrected induction [magnetometer] in arc, The front cover is inscribed: 'Register of Small Magnetic Instruments during the month of October 1846'. 1-30 October 1846