Before the 17th century the premier astronomical instrument was the astrolabe.  It was an early ancestor of the slide rule, theodolite and planetarium.  In a time before pocket watches it allowed the user to tell the time, predict astronomical events and do calculations in spherical geometry.

Steve H created a set of five videos that explain the instrument, its use and history.  That is available on this site.  These videos were based on a 30 minute talk on “The Astrolabe” Steve gave in July 2018.  This short presentation showed some simple uses for astrolabes, as well as how to design and make your own.

This video shows the presentation that was given.  Unfortunately there is no sound.  If the pictures don’t tell the full story you will have to catch Steve on a Tuesday open evening and ask him to narrate.