Ancient Observers

Mpemba was not the first to notice this. Aristotle wrote about it around 350 BCE, noting that hot water freezes faster in cold air. Francis Bacon mentioned it in 1620, and Rene Descartes recorded the same observation in 1637.

For centuries, these reports were dismissed as sloppy technique. Surely cold water, being closer to freezing, must freeze first? Yet the effect refused to disappear, and modern experiments confirm it is real but inconsistent — depending heavily on container shape, dissolved gases, and cooling rate.