Planispheric astrolabe with 3 latitude plates( 39�/ 42�, 48�/51� & 45� with a shadow dial scale on the reverse) and magnetic compass (adjacent to suspension ring), by Ferdinand Arsenius, Antwerp; Flanders; Belgium 1607-1618, [IC 233 - International Checklist]. Fitted with a. The reverse side is engraved with a Gemma Frisius universal projection with rule and pointer, with the alidade fitted to the front face. The womb of the mater (mother) is engraved with a �Quadratum Nauticum� (navigational quadrant) scale.