Description | Daily magnetic observations, in three columns, recording hourly position of the north end of the dip needle [degrees, minutes, seconds] at appointed observation times, with temperature in Fahrenheit.
With a title page: 'Horary Variation of the Magnetic Needle Barrack Square Ascension. 1830'.
Each page is headed: 'Increasing Readings denote North end going to the Eastward. Observations on the Diurnal Changes of a Magnetic Needle at Ascension'. |