| Description | Graphical representation of the horizontal force magnetometer, vertical force magnetometer, and hourly changes in declination from 2.00p.m. on 25 July [Singapore mean time] to 1.00p.m. on 26 July for vertical force and declination, the horizontal force readings continuing to 1.00a.m. on 28 July.
Headed [p.1]: 'Curves of the Hourly Changes of the Hor. & Vert. Force Magnetometers...'. Signed by C.M. Elliot. Inscribed [p.2]: 'Hourly Changes 25, 26 & 27 July 1843'. |