towards the Eaſt, whilſt that all the Stars ſeem'd to perform their diurnal Revolution from Eaſt to Weſt. To his Error they added a ſecond of much greater Conſequence, by imagining that the pretended Heaven of the fix'd Stars advanc'd one Degree eaſtward every hundred Years. In this Manner they were no leſs miſtaken in their aſtronomical Calculation than in their Syſtem of Natural Philoſophy. As for Inſtance, an Aſtronomer in that Age would have ſaid, that the Vernal Equinox was in the Time of ſuch and ſuch an Obſervation, in ſuch a Sign, and in ſuch a Star. It has advanc'd two Degrees of each ſince the Time that Obſervation was made to the preſent. Now two Degrees are equivalent to two hundred Years; conſequently the Aſtronomer who made that Obſervation liv'd juſt ſo many Years before me. 'Tis certain that an Aſtronomer who had argued in this Manner would have miſtook juſt fifty four Years; hence it is that the Ancients, who were doubly deceiv'd, made
