This chapter introduces yakhchāls, ancient Persian refrigeration systems dating back to 400 BC. It discusses their construction materials (a special mortar called serouge), impressive insulation properties, and the mystery surrounding their functionality.
Yakhchāls are ancient refrigeration systems from Persia.
Construction material: serouge (sand, clay, egg whites, lime, goat hair, and ash).
Exceptional insulation, comparable to modern materials.
If you lived in ancient Persia, you could do a lot worse in trying to cool things down than by building a yakhchāl. Today we break down how the early fridges worked.