x.ET. iv. Tycho Brake, and Copernicus. 57

Nor is it in the magnitude of bodies only thatthis endless gradation is to be observed. Of mo-tions, some are performed in moments of time,and others are finished in very long periods jsome are too stow, and others too swift to beperceived by us. So that wherever we turnourselves, we are lost in an endless labyrinth;and find frestr reasons, at every step, to adoreand venerate that Being, whose works are sovarious and hard to be comprehended.

But it is now time to leave these pleasing di-greffions, and to give you some account of thedifferent opinions of philosophers, concerningthe situation of the heavenly bodies, or the placewhich they possess in the universe. And in this en-quiry you will not be surprized to find, that theyare no less various and contradictory, than thoserelating to the figure and motion of the earth,as mentioned in a former letter. For mankindmust have made considerable advances in astro-nomy, before they could so far disengage them-selves from the prejudices of sense and popularopinion, as to believe in a doctrine so sublime,and remote from vulgar apprehension, as thatwhich the moderns have now firmly established.

The beginnings of sciences, as well as of otherthings, are uncertain and obscured with fables ;we collect, however, from several testimonies,that the true doctrine of the planetary motions

was