ObjID171-1
‹ Ancient Sundials
Dialface ID 170
Abstract
Part of gnomon hole is preserved in the top surface of the dial. This fragment is the upper right half of a conical dial. Six hour lines, including the meridian (6, 7, 8, 9, 10, 11), and parts of three engraved day curves are preserved.
Measurements
Measurement record: pipeline ObjID 171, matched to this dialface by inventory number.
| Quality grade | B (completeness 60 %) |
|---|---|
| Dial surface | cone (preferred, not decisive) · fit residual mm: cone 0.69, cylinder 0.70, sphere 3.06 |
| Latitude φ | 60.62 ± 0.77° (consensus of witnesses) |
| Klima | nearest Borysthenes (11.2 sigma) |
| Engraved lines | 6 hour lines, 2 day lines |
| Cone half-angle α | 12.8 ± 0.51° (cone residual on all points 0.71 mm) |
| Measured | 2026-06-12 20:30 |
What the dial shows at this latitude
| Winter solstice | Equinox | Summer solstice | |
|---|---|---|---|
| Noon altitude of the Sun | 5.7° | 29.4° | 53.1° |
| Noon shadow (gnomon heights) | 10.07 | 1.78 | 0.75 |
| Length of the day | 5.2 h | 12.0 h | 18.8 h |
| Length of a seasonal hour | 26 min | 60 min | 94 min |
Computed for the measured latitude with the obliquity of the JPL ephemeris at 101 BC (year -100). The latitude is the one the dial was made for, not a find-spot coordinate.
References
- – Gibbs, Sharon L., Greek and Roman Sundials, New Haven and London, 1976, p. 290.
- – Severino, Nicola, De Monumentis Gnomonicis apud graecos et romanos. Le meridiane greco-romane. La storia, il catalogo, gli articoli, Roccasecca, 2003, p. 23.
- – Winter, Eva, Zeitzeichen. Zur Entwicklung und Verwendung antiker Zeitmesser, Berlin and Boston, 2013, p. 494.
3D Models
