'The theory of the seasons and the signs of the zodiac', c 1851.
© Science Museum / Science & Society Picture Library
An astronomical diagram drawn and engraved by John Emslie, showing the phases of the Earth as it moves through the different signs of the zodiac during the course of a year. It also illustrates how the amount of daylight at various locations on Earth varies with the seasons due to the Earth's axis being tilted at an angle with respect to the ecliptic, the plane of the Earth's orbit around the Sun. Published by James Reynolds (174 Strand, London).