Timekeeping  /  The courtroom timer
c. 400 BC

The courtroom timer

Athenian courts timed speeches by water jar: equal shares, and bigger cases got more water.

The courtroom timer
The only surviving Athenian court clepsydra (below, mended) with a working replica above it. The painted word names the tribe Antiochis; “XX” is its capacity, two choes.Photograph: American School of Classical Studies at Athens, Agora Excavations, P 2084, photograph Craig Mauzy
Not a clock but a timer: a fixed measure of water runs out through a small tube, and when the jar is empty the speech is over.Drawing: Watch Historian
The need
Athenian juries heard several private suits a day, so each speaker had to be limited and seen to be treated fairly. Aristotle’s Constitution of the Athenians sets out the rule: water allotted by the value of the suit, and the same measure for each side.
How it worked
Unlike the Karnak clock this jar has no scale. It is filled to a hole marking two choes, about 6.4 litres, and empties through a bronze tube near the base in about six minutes. An official put his hand over the tube while documents were read out, so that reading time was not charged against the speaker.
What it changed
A simple, portable way to measure a fixed interval rather than tell the hour, the same job the sand glass would do in the Middle Ages. It is the physical counterpart of the written court rules.
Where it is now
Found in 1933 in a well beside the Tholos in the Athenian Agora; Agora Museum, Athens.

SourcesAristotle, Constitution of the Athenians 67 · Young, “An Athenian Clepsydra”, Hesperia 8 (1939) · Agora Excavations, P 2084

Suggest a correction

Spotted an error, or know a better source? Tell us. Notes go to the editor and are not published.