Astronomical Images : Figure showing the marking of the astrolabe

Johann Stoeffler

Astronomical Images

<p style='text-align: justify;'>Johann Stoeffler (1452-1531) was a mathematician, astronomer and instrument-maker who was appointed to the chair of mathematics and astronomy at the University of Tuebingen. He taught both Philipp Melanchthon and Sebastian Muenster and published amongst other things an almanac and work on calendar revision, as well as a book on the construction and use of the astrolabe. A celestial globe made in Stoeffler's workshop for the Bishop of Konstanz is preserved in the Landesmuseum Wuerttemberg in Stuttgart. <i>Elucidatio fabricae ususque astrolabii</i> was a work on the construction and use of the astrolabe which seems to have been widely read, going through more than fifteen editions in the sixteenth and early seventeenth centuries. The work was divided into two parts, the first on the construction of the instrument, and the second on its use. The latter section contained textual worked examples, as well as horoscopes and relatively realistic figures showing the astrolabe in use in surveying contexts. Throughout the first part of the work, on the construction of the instrument, Stoeffler used figures of the astrolabe's scales along with tables to clarify the details of the making of the instrument. While some attention was given over to very practical elements such as the screws that ought to be used and the ring from which the instrument could be suspended, most of the figures showed the inscription of the lines of the astrolabe. In these figures, such as the one shown here, fold-out sections were often used to make it easier to identify the circles and lines shown within the bounds of the instrument.</p>