Astrolabe, Regnerus Arsenius. Musée des Arts et Métiers, Paris
The Musée des Arts et Métiers in Paris has a large collection of astrolabes and these are rare as “hens teeth”. Today, we do not really understand the emphasis on astrology and astronomy in the past, but put simply, the heavens were considered quite literally heaven. The association of the phases of the moon and stars with tides, history and even menstrual periods was not lost on the ancients. They responded with astrology, an attempt to link the stars with events on earth. It reflected a worldview based on a highly esteemed Greek precedent and only lost credence during the “Age of Enlightenment” in the 18th century, giving way to our modern scientific, evidence based, worldview. The beautiful astrolabe shown above was made in Louvain, Netherlands in 1565 in the Arsenius workshop signed Regnerus Arsenius. An important university founded in 1423 helped to create the climate where the instrument workshop was founded in about 1530 and flourished through much of the century, directed at first by the cartographer Gerard Mercator (all modern maps use a “Mercator Projection”) in association with the mathematician and physician Gemma Frisius (famous for his Gemma rings and other things), and later by Gemma's 'nephew' Gualterus Arsenius. You can read more about this instrument here, it took about a year to make, it was delicate, complicated and expensive. There are only about 25 Arsenius astrolabes in the world, the one below is from the Galileo Museum in Florence, Italy.