Observational Methods and Procedures for the Mariner’s Astrolabe
The practical assessment of the accuracy of the mariner’s astrolabe has been the subject of discussion in The Mariner’s Mirror. This article gives further insight on this topic, based on period knowledge and statistical analysis of period and modern data. In addition, reference to more modern studies on this topic is given in an attempt to complete the list previously presented. It will not explore the influence of period tables for refraction and declination and the influence of longitude on the latter as these factors only affect the calculated latitudes, not the observations themselves.