This large orrery was made by Charles Butcher of Bedford, for Lord Trevor, Baron of Bromham. An eight-day clock rotates the planets. The calendar ring is four and half feet in diameter and has painted metal figures for the signs of the zodiac. The instrument was later owned by Dr Stephen Demainbray (1710-1782), a famous science lecturer, and was the most impresive in his collection. This picture shows the mechanism only.
© Science Museum / Science & Society Picture Library