Most people turn a car, bathroom or bedroom into a hotbox – a small, closed and unventilated space to smoke cannabis. But the first hotbox in history was made 2,500 years ago in a tent similar to the yurts of today’s Mongolian nomads. In his Nine Books of History the Greek historian Herodotus describes how the Scythians (equestrian warriors living north of the Black Sea) threw cannabis onto on hot stones in a closed tent and inhaled the vapour, to achieve a state of ecstasy, crying out from delight. The ‘civilized’ Greeks were appalled by this barbaric practice.