| Description | Macdonald analyses observations of diurnal magnetic variation taken in Calcutta [Kolkata, West Bengal, India] from February 1827 to February 1828 and includes this set of observations within his text. This text forms part of Macdonald's quest to find an 'unexceptionable' theory of magnetic variation. Includes one figure in the text.
Subject: Geodesy
Written by Macdonald in Summerlands, Exeter [Devon, England]. Received by the Royal Society on 3 June 1830. |