An unrecorded medieval astrolabe quadrant from <i>c.</i> 1300
Elly Dekker
Summary A detailed description of an as yet unrecorded astrolabe quadrant in a private collection is presented. date between 1291 and 1310 deduced from the calendrical data engraved on it. The characteristics newly recorded instrument have been compared with those six other medieval quadrants. appears to present early, if not earliest, stage development history quadrant. In comparison also distinguished by red black colours applied differentiate superposed scales names positions stars instruments were used establish connection two studied, Rouen Oxford, manuscript tradition construction quadrant, exemplified MS Oxford Ashmole 1522. three quadrants are shown stem star lists treatises astrolabes. For instruments, dated earliest latest, no such was found. Some hitherto recorded. Finally, competence later artisans has investigated analysing accuracy these instruments.
Annals of Science