One of a set of teaching cards published by James Reynolds & Sons, London, showing a chart drawn and engraved by John Emslie. The astronomical diagram shows the relative size of the planets and their distance from the Sun. The telescopic appearance of Jupiter, Saturn and Mars is also illustrated in colour. The top set of diagrams show how the planets Venus and Mercury display phases like our Moon along with the changing aspect of the rings of Saturn.
© Science Museum / Science & Society Picture Library