Opium poppy, 6th century.
© Science Museum / Science & Society Picture Library
Illustration from Dioscorides Codex Vindobonensis Medicus Graecus, which was probably published in Constantinople in the 6th century. Dioscorides (true name Pedianos Dioskurides) was a very influential author of herbals in clasical times. Born in Asia Minor, he was probably an army doctor. The original codex contains nearly 400 colour paintings of plants, along with lists of each plant's virtues and its medicinal properties. The opium poppy was used as a sleeping draught or pain killer, but too much could kill.