The Invention and Early Use of the Mariner’s Astrolabe

Abstract

The so-called mariner’s astrolabe attracts much attention. There are at least 40 publications, dating between 1917 and 2023 dealing directly with the subject plus many treatises on the history of navigation and nautical instruments that mention or describe the mariner’s astrolabe. Common to most of these publications are statements about the origin and/or first use of the mariner’s astrolabe which are mostly superficial, misleading or simply false. Almost all of them rely on prior publications, that are generally not cited, and if references are given they are wrong, poorly understood or misleading. These publications have meant that myths and baseless assumptions on the early history of European navigation have proliferated. This article tries to take stock of what we really know about the origin and the early use of an instrument widely used in navigation in the sixteenth and early seventeenth centuries. The sources of the presumed early dates, myths and assumptions are identified through an investigation of the nomenclature, graphical representations, textual evidence and material evidence relating to the mariner’s astrolabe.