Nilometer
Nilómetro
- Date
- c. 2500 BCE · confidence low
- Place
- Elephantine Island, Aswan, Egypt
- Credited to
- Pharaonic administration
- Field
- Knowledge & symbols
⚠️ Disputed: the sources disagree.
What it is
A graduated scale, or stairway with marks, that measured the height of the Nile's annual flood and from it predicted the harvest and the tax. Flood records were kept from very early times; the surviving stone nilometers are of later periods.
The Palermo Stone records flood heights from the early dynasties, but it was compiled centuries later; the surviving nilometers of Elephantine and Roda are late. The date of an earlier stepped instrument is an estimate.
What it led to
- harvest forecasting and setting of the land tax
- a hydrological record spanning millennia
- model for the Islamic nilometers of Roda island (861)