CHAP. IV.] PHYSICAL ASTRONOMY DEFICIENT. 127 



tliosc uognins are long since explodcrl, which asserted the 

 rapture of the fii*st mom and the solidity of the heavens, in 

 which the stare were supposed fastened like nails in the 

 vaulted roof of a hall, and other o])inions almost as silly ; 

 viz., that the zodiac has sevcml poles ; that there exists a 

 movement of resilience against the rapture of the first 

 motion ; that all parts of the firmament are wheeled round in 

 ])erfect circles, with ecctMitric and epicycles to preserve their 

 circular rotation ; that the moon has no influence over bodies 

 iiigher in the heavens ; the absurdity of which notions 

 have thrown men upon the extravagant idea of the diurnal 

 motion of the earth, an opinion which we can demonstrate 

 to be most false.'' But scarce any one has inquired into the 

 physical causes of the substance of the heavens, stellar and 

 interstellar; the different velocities of the celestial bodies 

 with regard to one another; the different accelerations of 

 motion in the same planet; the sequences of their motion 

 from east to west;' the progi'essions, stations, and retro- 

 gi'adations of the ])lanets, the stoppage and accidents of 

 their motion in perigee and apogee, the obliquity of their 

 motions ; why the poles of rotation are principally in one 

 quarter of the heavens ; why certain planets keep a fixed 

 distance from the sun, ttc. Inquiries of this kind have 

 hitherto been hardly touched upon, but the pains have been 

 chiefly bestowed in mathematical observations and demon- 

 strations ; which indeed may show how to account for all 

 these things ingeniously, but not how they actually are in 

 nature : how to represent the apparent motions of the 

 heavenly bodies, and machines of them, made according to 

 particular fancies ; but not the real causes and truth of 

 things. And therefore astronomy, as it now stands, loses its 

 .dignity by being reckoned among the mathematical arts, for 

 it ought ii . justice to make the most noble part of physics.'' 



• ^ That dt»etrine had been recently demonstrated by Galileo, and de- 

 fended by Gilbert. 



' That is, from west to east, according to the Copernican system. Ed. 



• ^ Banon maps out the entire region of human knowledge, breaking up 

 the old sections, and assigning to each science new boundaries more con- 

 formable in his view to strict philosophical notions than the old ; yet he 

 capriciously enough makes mathematics an essential jiart of metaphysics, 

 or inquiry into forais, and astronomy a compartment of mathematics, and 

 then decries this absurd arrangement as the notion of the age. It 

 is evident, however, that the age was innocent of the charge, and that 

 JJacon BTiaiched up the idea from the demonstrations which Copernicus, 



