The apparent movement of the sun across the sky is the result of Earth's rotation on its axis. (scientificamerican.com)
After three months, Quinnell removed the photographic paper the can contained, which now held a negative latent image of the apparent movements of the sun, which are caused by the Earth spinning on its axis. (newscientist.com)
«Here we have the more basic earlier observations being used, just simply following one of the extremes of the pendulumlike movement of the sun.» (sciencemag.org)