The programmes for the systematic exploration of the sky begun by astronomical observatories, the production of powerful instruments for observation and the understanding of the physical forces governing the universe helped to spread a new image of the cosmos based on an analogy with the clock, a device that was achieving ever more astonishing levels of sophistication and precision. Highly skilled clockmakers devoted their efforts to translating the new image of Galileo's and Kepler's universe into working mechanical devices capable of emulating its structure and movements. The evocative image of the universe as a machine was expressed emblematically by the complex mechanical planetaria - known as orreries after their first sponsor, Charles Boyle, 4th Earl of Orrery - first produced in the early 18th century. Orreries were enormously popular throughout the century and were used to teach the new cosmology, as we can see from numerous successful texts and pictures painted by leading artists.