This mezzotint is based on Joseph Wright of Derby's painting, first exhibited by the Society of Artists in 1766 under the title 'A Philosopher giving that Lecture on the Orrery, in which a lamp is put in place of the Sun'. The lesson explained the Copernican, or heliocentric, theory of the solar system by placing a candle in the centre of the orrery and letting the model planets revolve around it. This is a grand orrery, with metal hoops and circles above representing the celestial sphere, a projection of the earth's tilted axis and equator.

The lecture appears to be taking place in a domestic setting and three men, a woman, two young children and an older boy present. The painting was reproduced in numerous prints, testifying to its popularity. The rapt attention of the audience and the authority of the lecturer and his subject are heightened by the dramatic use of light, reproduced by Pether in imitation of Wright's original, which is now among the fine collection of his works in Derby Museum and Art Gallery. It was originally in the collection of Earl Ferrers, presumably at Staunton Harold, the Ferrers family seat not far from Wright's native Derby. This is one of quite a number of surviving early impressions of the plate before its full inscription was added, including the title given above.