Libations at an altar produced by fire, 1589.
© Science Museum / Science & Society Picture Library
Engraving: 'To construct an altar such that, when a fire is raised on it, figures at the side shall offer libations'. This diagram shows how heated water could power an automatic machine for making religious offerings. Illustration from 'Gli artifitiosi et curiosi moti spiritali di Herrone' (commonly called 'Pneumatics') by Hero of Alexandria, published in Ferrara in 1589.