6o. OF THE SYSTEMS OF PTOLEMY,

hours, and also in certain stated or periodicaltimes, agreeable to their annual changes andappearences. Every star was supposed to hgfixed in a solid transparent sphere, like crystal;and to account for their different motions, hewas obliged to conceive a number of circlescalled eccentrics and epicycles, which crossedand intersected each other in all manner of di-rections. And if any new motion was disco*vered, a new heaven of crystal was formed toaccount for it. So that, in short, as Mr. Fon-tenelle observes, heavens of crystal cost himnothing, and he multiplied them without end,to answer every purpose.

This absurd fy Hem is referred to by Milton,in the 8th book of his Paradise Lost, where,speaking of the dreams of visionary philoso-phers, concerning the nature and motion of theheavenly bodies, he fays,

- . . “ Or if they list to try

Conjecture, he his fabric of the heav’nsHas left to their disputes, perhaps to move

. His laughter at their quaint opinions wideHereafter, when they come to model heav’nAnd calculate the stars, how they will wieldThe mighty frame, how build, unbuild, contriveTo save appearances, how gird the sphereWith centric and eccentric fcribbl’d o’er.

Cycle and epicycle, orb in orb.”

The embarrassment of these circles appearedso great, that Alphonsus, king of Castile, a con-siderable