A System of Astronomy, on the Principles of Copernicus: Containing, Besides the Usual Astronomical Calculations, a Catalogue of Eclipses, Visible in the United States During the Present Century. E-book. Formato PDF John Vose   -  Forgotten Books, 2017  - 

To a spectator at the sun the planets would appear to move in harmonious order from west to east; he would probably take the period of Mercury as a standard for comparing the periods of planets; the paths ofthe planets would seem to cross each other.