Old Monitoring Equipments, 11th-17th century, Persia, A precious set of observational instruments used in astronomy, stars and the planets. An old group dating back to the 11th and 12th centuries, through which the mathematical and engineering theories adopted in astronomy and observations are proven. It is complementary to the various astronomical instruments, such as the astrolabe, clock, compass, telescope, stellar and geographical sphere. Including compasses of different sizes, rulers, triangles, and a protractor made of steel. Longest: 41 cm,