Positively the last times : theatre, Dover : Mr. D.F. Walker... has the honour to announce three astronomical lectures on the Eidouranion; or, large transparent orrery... to commence Saturday, 2d, Monday, 4th, and Tuesday, 5th, August, 1817.

Leaflet advertising a series of lectures about the earth in motion, the moon, tides, planets and satellites, probable construction of the universe, a new zodiac, a plurality of worlds and a comet that rises and falls 400 feet. These were accompanied by music on the celestina (an invention of Mr. Walker) and given at the Dover theatre in Summer 1817.