The angle, at the point of observation, between the vertical plane through the observed object and the vertical plane in which a freely suspended, sym-metrically magnetized needle, influenced by no transient or artificial magnetic disturbance, will come to rest. (187) Magnetic azimuth is generally reckoned from magnetic north (0°) clockwise through 360°. Such an azimuth should be marked as being magnetic, and the date of its applicability be given.