Instruments · Sundial
Sundial, Egypt, 600 BCE
- Maker / attribution
- Unrecorded in source
- Date
- 600 BCE
- Historical period
- Medieval Period (500 – 1400)
- Country of origin
- Egypt
- Place
- Ancient Egypt, Egypt
- Object type
- Sundial
- Dimensions
- overall: 25 mm x 93 mm x 22 mm, 0.098 kg
- Holding institution
- Science Museum Group, London
- Accession / object no.
- 1929-585
- Credit line
- Dr Howard Carter
- Catalogue title (original)
- Egyptian Merkhet
Record summary
Held and catalogued by Science Museum Group, London (object number 1929-585), this is a sundial, made in Ancient Egypt, Egypt, dated 600 BCE. The Atlas places it in the Medieval Period period (500 – 1400) of its Instruments collection. Recorded dimensions: overall: 25 mm x 93 mm x 22 mm, 0.098 kg. The record is illustrated with 4 photographs.
Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.
Catalogue description
Science Museum Group description
The hieroglyphic inscription indicates that this instrument was the property of Bes, son of Khonsirtis (Khensardais var.), an astronomer priest of the god, Horus of Edfu in Upper Egypt. As a timekeeping instrument, it would have been used to determine the hours by the sun during the day and by onserving the passage of selected stars across the north-south meridian during the night. As a surveying instrument, it would have been used to layout axes of buildings.
Historical context
Medieval Period (500 – 1400)
Su Song's astronomical tower in Song China, al-Jazari's automata, and the first European weight-driven verge clocks.
Astronomers in the Islamic world refined the astrolabe, quadrants and sundials for prayer times and astronomy; through al-Andalus these instruments reached Latin Europe, where they were taught at universities.
Read the period in the timelineMore instruments from this periodEarlier: Classical Antiquity
Atlas type guide
Sundials and solar time-finders
A sundial tells time from the position of a shadow cast by a gnomon or style. Because the sun's apparent motion depends on latitude, every fixed dial is laid out for a particular latitude, and portable dials either carry a latitude scale or are made for one region. Sundials show local apparent solar time, which drifts against mean (clock) time by up to about sixteen minutes over the year — the equation of time.
Portable dials were the pocket instruments of the sixteenth to eighteenth centuries. Nuremberg and Augsburg workshops produced folding ivory diptych dials with inset compasses; English and French makers sold brass horizontal dials, ring dials and the Butterfield type; Japanese and Chinese makers had their own traditions of compass dials. After mechanical watches became reliable, dials remained in use for setting them, and nineteenth-century heliochronometers were built to correct directly for the equation of time.
What to look for
- The latitude engraved on the dial plate or a latitude arc on the gnomon — it shows where the dial was meant to be used.
- The type of hour lines: equal (equinoctial) hours, Italian or Babylonian hours counted from sunset or sunrise, or unequal temporal hours on early and Islamic instruments.
- An inset magnetic compass and whether a magnetic-declination mark is drawn on its card — a useful dating clue because declination changes over time.
- Maker's signatures and town marks: Nuremberg compass-makers (Kompassmacher) often struck a personal mark and the town's punch.
- Additional scales such as lunar volvelles, wind roses, perpetual calendars or lists of cities with their latitudes.
Dating clues
- Ivory diptych dials are characteristic of Nuremberg between about 1500 and 1700.
- Butterfield-type dials with a bird-shaped adjustable gnomon point to Paris workshops from the late seventeenth century onward.
- Equation-of-time tables engraved on the plate became common after the mid-seventeenth century, once pendulum clocks made the difference between solar and mean time obvious.
General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.
Read next:The history timeline
Related records
Instruments · 569
Metronome, France, 569
Science Museum Group, London
Instruments · 646
Water clock, Sri Lanka, 646
Science Museum Group, London
Instruments · 10th century
Quadrant by Muhammad ibn Mahmud, Iran (Persia), 10th century
The Metropolitan Museum of Art, New York
![Brass Moorish planispheric astrolabe with five plates, a shadow dial on the reverse and silver studs on the rete, c. 1150, IC 1058 [international checklist].](/__l5e/assets-v1/9610b3f9-7674-4e62-a0ab-0875c37c053f/brass-moorish-planispheric-astrolabe-with-five-plates-a-shad-thumb.jpg)
Instruments · 1145-1155
Brass Moorish planispheric astrolabe with five plates, a shadow dial on the reverse and silver studs on the rete, c. 1150, IC 1058 [international checklist].
Science Museum Group, London
Instruments · 1221
Astrolabe by Mohammad ibn Bekr ibn Mohammad Al Rashidi Al-Abari, Iran (Persia), 1221
Science Museum Group, London
Instruments · 1290–1292
Astrolabe by ‘Umar ibn Yusuf ibn ‘Umar ibn ‘Ali ibn Rasul al-Muzaffari, Yemen, 1290–1292
The Metropolitan Museum of Art, New York
Instruments · 1295-1305
Astrolabe, France, 1295-1305
Science Museum Group, London
Instruments · 1300-1400
Astrolabe of cast sheet brass, with additional cast elements, engraved, France; 1300-1400
Victoria and Albert Museum, London