© Science Museum/Science and Society Picture Library
The Enlightenment of the eighteenth century set running a 'clock', joining science and reason with mechanical invention, a linkage which has had a profound and continuing influence for the world.
The clock shown here, made in about 1780 by Benjamin Vulliamy, was the principal timekeeper at the King's Observatory at Richmond, established in 1769 by George III.
Delicate friction rollers act as the bearings of the wheelwork, reducing the need for lubrication. The clock was fitted with the almost frictionless 'grasshopper' escapement invented by the pioneer of the chronometer, John Harrison, whose clocks had enabled seamen to calculate their longitude accurately for the first time. The elaborate gridiron pendulum, also introduced by Harrison, ensured that the clock kept good time as the temperature in the Observatory varied.
Accurate clocks, which relied on a pendulum, were an innovation of the seventeenth-century scientific revolution. In the eighteenth century astronomy, that keynote of the new sciences, found novel uses for specialised variants of these clocks. As the movements of stars and planets were timed, so the geometry and rhythms of the universe came to be better understood.