Water clocks were used as time keeping instruments in ancient Egypt from at least the New Kingdom until the end of pharaonic history. Most of the surviving full-sized water clocks are made of stone and are inscribed inside and out. All but one of them are 'outflow' water clocks, meaning that time was indicated by the water level falling past scale marks as the water ran out of the vessel. The remaining one is apparently an inflow water clock (water level rising past scale marks as the water ran into the vessel). Most water clocks have been found in pieces; fragments of the same vessel may currently be in different collections. The list below does not include smaller water clocks without scales, which may be models rather than real vessels.

The ID column gives a sequential number for each vessel (fragments are referred to by an additional lower-case letter, Fr.) based on the system of Lodomez (2007). Most objects are poorly provenanced, but the inscribed name gives a date reference. The exterior decoration of outflow water clocks sometimes included an astronomical representation (AR). These vessels are cross-referenced to the relevant page in the astronomical representations section of the database. 

Outflow Water Clock


Inscribed toNotesAR?Fr.Current locationCatalogue No.
WCO 1 Amenhotep III Temple of Karnak, New Kingdom Yes   Egyptian Museum, Cairo JE 37525
WCO 2 Nekau II Late Period, 26 Dynasty Yes   Egyptian Museum, Cairo JE 67096
WCO 3    Alexander the Great    Tell el-Yahudiya, late 4th C BC. Fragment a is actually two attached fragments. No    a British Museum, London BM EA933
b Musée du Louvre, Paris E 30890
c Ägyptisches Museum, Berlin ÄM 30508
d In private hands -
WCO 4  Alexander the Great     No  a Hermitage, Saint Petersburg ДВ-2507a
b Museo Nazionale, Naples 2327
WCO 5 Alexander the Great   No   Brooklyn Museum, New York 57.21.1
WCO 6 Philip Arrhidaeus Tell el-Yahudiya, c. 320 BC No   British Museum, London EA938
WCO 7        No  a Museo Egizio, Turin Supp. 8
b Musées royaux d'Art et d'Histoire, Brussels E.04782
WCO 8     No   Pushkin Museum, Moscow I.1.a.5955
WCO 9     No   Ephesus Unknown
WCO 10 Ptolemy II     Yes a Musée du Louvre, Paris N 664
b Thorvaldsens Museum, Copenhagen H351
WCO 11 Ptolemy II Found in Rome in the Iseo Campense area, according to the museum label No   Museo Barracco, Rome MB 27
WCO 12     No   Hermitage, Saint Petersburg ДВ-2507b
WCO 13 Hadrian Found in ruins in Villa Bonelli, outside Porta Portese, Rome (Porter & Moss 1960) No   Ägyptisches Museum, Berlin ÄM 19556
WCO 14     No   Museo Archeologico, Florence 2613
WCO 15   Temple of Serapis in Alexandria. Assigned a find number in Rowe & Drioton (1946). No   Unknown P.9619
WC? 16   This fragment seems to be curved. The decoration is consistent with other outflow water clocks. No   Museo Egizio, Turin Supp. 3524
WCO 17   Unknown, possibly Saqqara? Yes   Museo Archeologico, Florence 12290
WCO 18  ?Nectanebo     No  a Petrie Museum, London UC55487
b In private hands -
WCO 19     No   Oriental Institute Museum, Chicago E16875
WCO 20   Described by Borchardt (1920) No   Unknown -
WCO 21 Ptolemy II Nineveh, acquired by Frankfort in 1930 (Ritner 2016) Yes   Oriental Institute Museum, Chicago A7125
Inflow Water Clock
ID in this catalogueProvenanceAR?Current locationCatalogue number
WCI 1 Edfu No Egyptian Museum, Cairo TR