This nocturnal watch ––horologium nocturnale– is an astronomical instrument used to measure the time through the observation of the Pole Star and the position of brigth stars in the celestial sphere.
The Nocturnal is made of three concentric brass disks, which can turn freely with respect to each other around a central ring.
This nocturnal is a reproduction of the one made in 1570 by Girolamo della Volpaia (History of Science Museum of Florence). Because it was made before the Gregorian reform (1582) and its creador had not very accurate calculation boards, to use this instrument correctly one must add 38 days to observation date. Made of brass and printed markings, this beautifully finished working instrument will adorn, delight, educate and entertain.
Max Height: 6.5"Diameter: 5.51"Thickness: 0.12"