- Museum number
Nocturnal, disc-dial and horary-quadrant; brass; obverse: nocturnal; superposed vertical disc-dial with folding gnomon; reverse: in four quadrants: quadrant dial for equal hours; sinical quadrant; quadrant dial for unequal hours; scale of umbra versa and umbra recta; rotating alidade with sights(broken) and scale of zodiac signs.
- Production date
Diameter: 74 millimetres
- Curator's comments
- Ward 1981
Obverse, a nocturnal with handle at 3 September, and equinoxes at 20 March and 23 September. Superimposed on this, a vertical disc with folding gnomon, and apertures showing the moon's phase according to its age . This disc with scrolled engraving at its centre.
Reverse, in four quadrants:
1. A quadrant dial for equal hours.
2. A sinecal quadrant.
3. A quadrant dial for unequal hours.
4. A scale of umbra versa and umbra recta, reading 0-12 for each.
A rotating alidade with sights (the latter now broken off) replaces the usual plumb-bob for the quadrants. A scale of zodiac signs is marked on the alidade as well as on the dial face, adjoining the equal-hours quadrant.
- Not on display
Latest: 3 (Nov 2016)
3 (Dec 1995) Sticky label. Sighting vanes missing.
- Acquisition date
- Britain, Europe and Prehistory
- Registration number