Muhammad ibn Abi Bakr al Ibari century) Astrolabe with geared calendar, Oxford, Museum of the History of Science. Of Persian origin, and one of the oldest complete devices of it's like in the museums collection.
Astrolabe - Astrolabes are problem solving instruments – they compute things such as the time of day according the position of the sun and the stars in the sky. Like a computer, you input information and then you receive output. They were ty